government of karnataka j{uvktbs.kar.nic.in/new/website textbooks/class10/10th...i government of...
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i
Government of Karnataka
MATHEMATICS
Karnataka Text Book Society (R.)100 Feet Ring Road,
Banashankari 3rd Stage, Bengaluru - 85
2015
10
Tenth Standard
J{UV
_amR>r _mÜ`_Marathi Medium
B¶Îmm Xhmdr
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Preface
The Textbook Society, Karnataka has been engaged in producing new textbooksaccording to the new syllabi which in turn are designed on NCF – 2005 since June 2010.Textbooks are prepared in 12 languages; seven of them serve as the media of instruction.From standard 1 to 4 there is the EVS, mathematics and 5th to 10th there are three coresubjects namely mathematics, science and social science.
NCF – 2005 has a number of special features and they are:· connecting knowledge to life activities· learning to shift from rote methods· enriching the curriculum beyond textbooks· learning experiences for the construction of knowledge· making examinations flexible and integrating them with classroom experiences· caring concerns within the democratic policy of the country· make education relevant to the present and future needs.· softening the subject boundaries- integrated knowledge and the joy of learning.· the child is the constructor of knowledge
The new books are produced based on three fundamental approaches namely.Constructive approach, Spiral Approach and Integrated approachThe learner is encouraged to think, engage in activities, master skills and competencies.The materials presented in these books are integrated with values. The new books arenot examination oriented in their nature. On the other hand they help the learner in thetotal development of his/her personality, thus help him/her become a healthy member ofa healthy society and a productive citizen of this great country, India.Mathematics is essential in the study of various subjects and in real life. NCF 2005proposes moving away from complete calculations, construction of a framework of concepts,relate mathematics to real life experiences and cooperative learning.Many students have a maths phobia and in order to help them overcome this phobia,jokes, puzzles, riddles, stories and games have been included in textbooks. Each conceptis introduced through an activity or an interesting story at the primary level. Thecontributions of great Indian mathematicians are mentioned at appropriate places.Textbooks for students X have a special significance. As any other new textbook they helplearners’ master skills and competencies and at the same time there is going to be apublic examination based on them.
The Textbook Society expresses grateful thanks to the chairpersons, writers,scrutinisers, artists, staff of DIETs and CTEs and the members of the Editorial Board and
printers in helping the Text Book Society in producing these textbooks.
Nagendra KumarManaging Director
Karnataka Textbook Society®Bengaluru, Karnataka
Prof G.S. MudambadithayaCoordinator
Curriculum Revision and Textbook PreparationKarnataka Textbook Society®
Bengaluru, Karnataka
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Chairperson’s note
This tenth standard mathematics textbook is prepared for the revised syllabusof Karnataka State based on the recommendations made by NCF 2005. It isdesigned to support the two major suggestions made by NCF 2005.
The higher aim of mathematics education should be to develop the innerresources in children. That is, development of mental abilities such as logi-cal and abstract thinking, reasoning, analysing, problem solving etc.
The mode of transaction should be based on contructivism, which facilitatethe learners to construct their own knowledge.
Conceptual understanding of basic ideas and problem solving are the twomain components of mathematics learning. Hence, this textbook is prepared insuch a way to facilitate mathematics learning by doing mathematics and wellbalanced text and exercises.
The salient features of this text book are
Each unit begins with real life situations or activities that engage studentsin learning tasks.
Each concept in each unit is provided with suitable exploring activities andillustrations.
The text is presented in simple language and logical manner with suitablehands on and minds on activities.
The units where theorems are included, both practical activity for stating thetheorem and logical proof for proving the theorem are discussed.
Each theorem is followed by numerical problems and riders. Equalweightage is given to problems and riders on theorems, its converse andcorollories.
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Questions are raised wherever possible to promote thinking and doanalysis.
Additional information is provided in boxes with the heading “know this”.This is to motivate students and create interest in the subject.
Questions and statements with headings “Try” and “Discuss” are givenfor promoting inquiry and co-operative learning strategies.
Each unit ends with a flow chart where all the ideas learnt in the unit areprovided through concept mapping. Students with the guidance of teacherscan generate better concept maps.
This text book is made to be both learner friendly and teacher friendly. We,the Tenth standard mathematics text book committee members hope that thetext book will pave a suitable path for making mathematics learning joyful andmeaningful.
We would be greatful for constructive suggestions and comments fromexperts, teachers, students and parents for further improvement of this book.
Dr. G. VijayakumariChairperson
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Text Book Committee
Chairperson :Dr. Vijaya Kumari G. - Associate Professor, Vijaya Teachers College (CTE),4th block, Jayanagar, Bengaluru - 11.Members :1) Dr. Y.B. Venkatesh - Lecturer, Govt. P.U. College, Bidadi, Ramanagara District.2) Sri V. Ravikumar - Senior Lecturer, DIET, Ilakal, Bagalkot District.3) Sri Narasappa - Head Master, Sri Saraswati Vidyaniketana, Dommasandra,
Bengaluru.4) Sri T.K. Prasanna Murthy - Asst. teacher, Vijaya High School, Jayanagar,
Bengaluru.5) Smt. M. N. Deepa Rao - Asst. Teacher, Sri. N.K.S.E.H.S, D.V.V. Gujarati Shala,
Majestic Circle, Bengaluru.6) Sri Tharakesh (Artist) Drawing Teacher, Government High School,
Bannitalapura, Gundlupet Taluk, Charamarajanagar Dt.
Scrutinizers :
1) Dr. B.J. Venkatachala, Prof. H.B.C.S.E (T.I.F.R) Mathematics Dept. IISC,Bengaluru.
2) Sri K. Krishna Iyengar, Retired B.E.O., Bengaluru.
Editorial Committee Members:1) Dr. R. Raveendra - N.C.E.R.T Director (Retd.), Banashankari III stage,
Bengaluru.2) Dr. B.S. Upadhyaya - Professor, Extension & Education Division, R.I.E., Mysuru.3) Dr. V.S. Prasad - Professor, Mathematics Department, R.I.E., Mysuru.4) Dr. Sharath Sure - Asst. Professor, Azim Premji University, P.E.S. School of
Engineering Campus, Electronics City, Bengaluru.Chief Advisor :1) Sri Nagendra Kumar, Managing Director, KTBS, Bengaluru.2) Sri Panduranga (Incharge), Deputy Director, KTBS, Bengaluru.
Translator Committee :1. Sri. A. S. Desai (Chairman), (H.M.) B.K. Model High School, Camp, Belagavi.
2. Sri. J. U. Ghadi, (H. M.) New girls High School, Goaves, Shahapur, Belagavi.
3. Sri. A. V. Patil, (A.M.) Marathi Vidyalaya, Vijaypura.
4. Sri. P. J. Patil (A.M.) The Volkart Academy Gokak Falls, Gokak.
Chief Co-ordinator :Prof. G.S. Mudambaditaya, Co-ordinator, Curriculum revision and textbookpreparation, KTBS, Bengaluru.
Programme Co-ordinator :Smt. Shashikala R.N. - Assistant Director, KTBS, Bengaluru.
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1. gQ> 1 - 15
2. H«$‘ 16 - 55
3. dmñVd g§»¶m 56 - 70
4. H«$‘doe Am{U g§doe 71- 94
5. g§^mì¶Vm 95 - 120
6. g§»¶memó 121 - 145
7. H$aUr 146 - 161
8. ~hþnXr 162 - 190
9. dJ©g‘rH$aUo 191 - 224
10 dVw©io 225 - 260
11. g‘ê$n {ÌH$moU 261 - 300
12. nm¶W°Jmoag à‘o¶ 301 - 313
13. {ÌH$moU{‘Vr 314 - 348
14 gh{ZXo}eH$ y{‘Vr 349 - 368
15 ‘mnZo 369 - 407
n¶m©¶r àûZ 408- 417
J{UVr Z‘wZo (nwadUr) 418-421
A.Z§ àH$aUo n¥ð> H«$‘m§H$
AZwH«$‘{UH$m
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1*gQ>m§Mm g§¶moJ Am{U N>oXZ ¶mdarb
H«$‘{Zanoj Am{U gmhM¶© JwUY‘©.* gQ>m§Mm g§¶moJ Am{U N>oXZ ¶mdarb H«$‘{Zanoj Am{U gmhM¶© JwUY‘mªMm nS>Vmim..* gQ>mdarb {dVaU JwUY‘©.* S>r>-‘m°J©ÝgMm {Z¶‘* n(A) + n(B) = n(A B) + n(A B).
Am°JñQ>g {S> ‘m°J©Z (1806-1871)¶m§Mm OÝ‘ ^maVm‘ܶo Vm{‘iZmSy> ‘Yrb‘XÿamB© ¶oWo Pmbm hmoVm. Vo 7 ‘{hݶm§MoAgVmZm ˶m§Mo Hw$Qw>§~ B§½b§S>‘ܶo ñWbm§VarVPmbo. ˶m§Zr Amnbo {ejU B§½b§S>‘Yrb{Ì{ZVr {dÚmb¶ Ho$på~«O ‘ܶo KoVbo.{S>‘m°J©ÝgMm {Z¶‘ gQ>m§Mm g§¶moJ, N>oXZAm{U H$moQ>r ¶m ‘yb yV {H«$¶m§er g§~§YrVAmho.
¶m KQ>H$m‘wio Vwåhmbm ¶m§Mo gwb^rH$aU hmoVo,* g§¶moJ Am{U N>oXZ gQ>mdarb H«$‘{Zanoj Am{U gmhM¶© JwUY‘mªMo ñnï>rH$aU* gQ>m§Mm g§¶moJ Am{U N>oXZ ¶mdarb H«$‘{Zanoj Am{U gmhM¶© JwUY‘© nS>VmiUo.* gQ>m§À`m {dVaU JwUY‘m©Mo ñnï>rH$aU Am{U nS>VmiUo.* S>r-‘m°J©ÝgMm {Z¶‘ ñnï> H$aUo.* S>r-‘m°J©ÝgMm {Z¶‘ nS>VmiUo.* gQ>mVrb g§~§Y ñnï> H$aUo.. n(A) + n(B) = n(A B) + n(A B)* gQ>m§Mm g§~§Y dmnéZ CXmhaUo gmoS>{dUo.* doZ AmH¥$Vr H$mT>Uo.
God created infinity, and man, unable tounderstand infinity, created finite sets.
-Anonymous
Sets gQ
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Sets 3
A B = B A. Am{U A B = B A
XmoZ gQ>m §Mm g§¶moJAm{U N> ooXZ gQ> hm H«$‘{Zanoj AgVmo.
{Q>n : EH$mM doir XmoZ gQ> KodyZ, H$moU˶mhr g§»¶oMo g§¶moJ qH$dm N>oXZ gQ> aMbo OmD$ eH$VmV. g§¶moJ
Am{U N>oXZ gQ> ho Zoh‘r H«$‘{Zanoj AgVmV.
(iii) XmoZ g§¶moJ gQ>m§Mm gmhM¶© JwUY‘© :(Associatine property of union of two sets)
A, B Am{U C ¶m VrZ gQ>m§Mm {dMma H$am.
A= {a, b, c, d }, B = {b, c, e, f }, C = {c, e, f, g }
àW‘ AmnU A Am{U B gQ>m§Mm g§¶moJ gQ> H$mTy>.
A B = {a, b, c, d } {b, c, e, f } = {a, b, c, d, e, f }
AmVm, AmnU ¶m ’$b{ZînÎmr gQ>mMm C gQ>mdarb g§¶moJ gQ> H$mTy>.
(A B) C = {a, b, c, d, e, f } {c, e, f, g }
(A B) C = {a, b, c, d, e, f, g } .....(i)
¶oWo, AmnU àW‘ (A B) H$mTy> Am{U Z§Va (A B) gQ>mMm C gQ>mdarb g§¶moJ gQ> H$mTy>.
’$b {ZînÎmr H$moUVr? àW‘ AmnU B Am{U C g§¶moJ gQ> H$mTy> Am{U Z§Va ˶m§Mm A darb g§¶moJ gQ>
H$mTy>.
B C H$mTm
B C = {b, c, e, f } {c, e, f, g} = {b, c, e, f, g }
AmVm AmnU A gQ>mMm (B C) darb g§¶moJ gQ> H$mTy>.
A (B C) = {a, b, c, d } {b, c, e, f, g }
A (B C) = {a, b, c, d, e, f, g} ......(ii)
(i) Am{U (ii), ¶m§Mr VwbZm H$éZ, Amåhmbm {Xgob H$s Vo g‘mZ AmhoV.
Amåhr Agm {ZîH$f© H$mTy> H$s,
(A B) C = A (B C)
gQ>m§Mm g§¶moJ hm gmhM¶© AgVmo.
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Sets 5
(i) Am{U (ii) ¶m§Mr VwbZm H$am. Amåhmbm {Xgob H$s XmoÝhr g‘mZ AmhoV åhUyZ AmnU {ZîH$f© H$mTy> H$s
(A B) C = A (B C)
gQ>m§Mm N> oXZ hm gmhM¶© AgVmo.doZ AmH¥$Vr H$mTy>Z N>oXZ gQ>m§Mm gmhM¶© JwUY‘© VnmgyZ nmhÿ.
nm¶ar 1 : A, B Am{U C. ho gQ> AmhoV. nm¶ar 2 : A B nm¶ a r 3 : (A B) C
2
4
6
8
A
1
2
4
3
B
4
6
5
7
C A B68
13
24
C4 56 7
138
65 7
24
A B
C
.......(i)
nm¶ar 4 : B C nm¶ar 5 : A (B C)B C1
23
5
64
12
3
5
64
A2 64 8
138
65 7
24
A B
C.............(ii)
g_r (i) Am{U (ii) _Yrb aoIm§H$sV ^mJmMr VwbZm H$ê$Z AmnU Agm {ZnH$f© H$mT>y H$s (A B) C = A (B C)
(V) gQ>m§Mm {dVaU JwUY‘© :(Distributive property of Sets )
Amåhr Aä¶mgbobo Amho H$s, H«$‘{Zanoj JwUY‘© Am{U gmhM¶© JwUY‘© g§¶moJ Am{U N>oXZ gQ>mdarb
{H«$¶mgmR>r bmJy nS>VmV.
ñ‘aU H$am H$s, darb à˶oH$ JwUY‘© ñnï> H$aVmZm gQ>m§À¶m {H«$¶on¡H$s ’$º$ EH$M, EH$ Va g§¶moJ qH$dm
N>oXZ {H«$`m dmnabr Amho.
gQ>mdarb XmoÝhr {H«$¶m N>oXZ Am{U g§¶moJ ¶m VrZ gQ>mgmR>r dmnaUo e³¶ Amho H$m? Oa Vgo Agob Va¶m KQ>Zo‘ܶo H$moUVm JwUY‘© AmT>iVmo. ¶m{df¶r Aä¶mg H$é.
¶m {df¶r AmnU Aä¶mg H$ê$.
g§¶moJ gQ>mMm N> oXZ gQ>mdarb {dVaU JwUY‘©:
Imbrb VrZ gQ>m§Mm {dMma H$am.
K= {3, 5, 7, 9}, L = {5, 8, 9}, M = {1, 2, 3, 9}
K (L M) H$mT>m.
L Am{U M. Mm N>oXZ gQ> H$mT>m.
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Sets 7
K (L M) = {x, y, z, t} {r, s, t, y, z} = {t, y, z}.....(i)
AmVm AmnU K d L; Am{U K d M ¶m§Mm N>oXZ gQ> H$mTy>, Am{U Z§Va ¶m XmoÝhtMm g§¶moJ gQ> H$mTy>.
K L = {x, y, z, t} {y, z} = {y, z}K M = {x, y, z, t} {r, s, t} = { t }
AmVm, K L Am{U K M ¶m gQ>m§Mm g§¶moJ gQ> H$mTy>.
(K L) (K M) = {y, z} {t}(K L) (K M) = {t, y, z}..................... .(ii)
(i) Am{U (ii) déZ AmnU nmhÿ eH$Vmo H$s, XmoÝhr gQ> gmaIoM AmhoV.
¶mdéZ AmnU {ZîH$f© H$mTy> eH$Vmo H$s, K (L M) = (K L) (K M)
gQ>mdarb {H«$¶mgmR>r {dVaU JwUY‘© bmJy nS>Vmo.
gQ>m§Mm N>oXZ gQ> hm g§¶moJ gQ>mdarb {dVaU JwUY‘© Amho.
AmVm AmnU doZ AmH¥$Vr H$mTy>Z N>oXZ gQ>m§Mm g§¶moJ gQ>mdarb {dVaU JwUY‘© VnmgyZ nmhÿ.
i.e. K (L M) = (K L) (K M)
S>mdr ~mOy = K (L M) COdr ~mOy = (K L) (K M)
K L
K L
M
K
K L
L
(( )) MKM
M
K L
K
L
L
K
MM
M
K
K L M
L
( )
(i) Am{U (ii)‘Yrb aoIm§H$sV ^mJmMr VwbZm H$éZ, AmnU {ZîH$f© H$mTy> eH$Vmo H$s,K (L M) = (K L) (K M)
gQ>m§Mm N>oXZ gQ> hm g§`moJ gQ>mda {dVaU JwUY_© Amho.
S>r-‘m°J©ÝgMm {Z¶‘ (De Morgan's Law)
AmVm n¶ªV AmnU gQ>mdarb {H«$¶m§da H«$‘{Zanoj, gmhM¶© Am{U {dVaU JwUY‘© bmJy nS>Vmo ho Aä¶mgbo Amho.
ñ‘aU H$am H$s, {Xboë¶m gQ>mMm H$moQ>rgQ> gwÜXm H$gm H$mT>bm OmVmo ho AmnU Aä¶mgbo Amho.
{Xboë¶m XmoZ gQ>m§Mm H$moQ>r gQ>mer H$moUVmhr g§~§Y Amho H$m? ¶mMm Aä¶mg H$é.
Imbrb H$moï>H$ nmhm. à˶oH$ CXmhaUm‘ܶo XmoZ gQ> {Xbobo AmhoV. ˶m§Mm H$moQ>rgQ> H$mT>m Am{U à˶oH$
ñV§ m‘ܶo Z‘yX Ho$boë¶m {H«$¶m H$am. n{hbo EH$ Vw‘À¶mgmR>r Ho$bobo Amho. ¶m‘m{hVrdéZ Vwåhr H$moUVm {ZîH$f©H$mTy> eH$Vm H$m?
............. .(ii)................ .(i)
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Sets 9
(i) S>r>-‘m°J©ÝgMo {Z¶‘ (i) : (A B) I = AI B I S>r-‘m°J©ÝgMo {Z¶‘ (ii) (A B) I = AI BI
A B A B
BA
A B
A B
A BA B A B
BA
A B
A B
A B
A B
I S>r-‘m°J©ÝgMo {Z¶‘
* (A B)I = AI BI
* (A B)I = AI BI
ñdmܶm¶ 1.1
1. g§¶moJ Am{U N>oXZ gQ>m§Mm H«$‘{Zanoj JwUY‘© Vnmgm.
A = {l, m, n, o, p, q} B = {m, n, o, r, s, t}
2. P = {a, b, c, d, e}, Q = {a, e, i, o, u} Am{U R = {a, c, e, g}, {Xbobo AmhoV Va g§¶moJ Am{U N>oXZgQ>m§Mm gmhM¶© JwUY‘© Vnmgm. 3. Oa A = {–3, –1, 0, 4, 6, 8, 10}, B = {–1, –2, 3, 4, 5, 6}, Am{U C = {–6, –4, –2, 2, 4, 6}
Va A (B C) = (A B) (A C) ho XmIdm.4. Oa U = {4, 8, 12, 16, 20, 24, 28}, A = {8, 16, 24}, B = {4, 16, 20, 28}.
Va i) (A B)I = AI BI Am{U (ii) (A B)I = AI BI
5. Oa A = {1, 2, 3}, B = {2, 3, 4, 5}, C = {2, 4, 5, 6} hoU = {1, 2, 3, 4, 5, 6, 7, 8} Mo CngQ> AmhoV (A B)I = AI BI Am{U (A B)I = AI BI.hoVnmgm.
6. Oa A = {2, 3, 5, 7, 11, 13}, B = {5, 7, 9, 11, 15} ho U = {2, 3, 5, 7, 9, 11, 13, 15}. MoCngQ> AmhoV Va S>r-‘m°J©ÝgMo {Z¶‘ Vnmgm.
7. Imbrb CXmhaUm§À¶m ñnï>rH$aUmgmR>r doZ AmH¥$Vr H$mT>m.(i) (A B) (ii) ( A B)I (iii) AI B (iv) A BI
(v) A \ B (vi) A B \ C) (vii) A B C) (viii) C B A)
(ix) C B \ A) (x) A \ B C) (xi) (A \ B) (A \ C) (xii) (A B) \ A C)
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Sets 11
Vwåhr nmhmb H$s,
n(A) Am{U n(B) Mr ~oarO n(A B) Am{U n(A B) À¶m ~oaOoer g‘mZ Amho.
åhUyZ AmnU Ago {bhÿ eH$Vmo H$s, n(A) + n(B) = n(A B) + n(A B)
Oa ¶m g§~§YmVrb H$moUVrhr VrZ nXo ‘mhrV AgVrb Va nXm§Mr AXbm~Xb H$éZ AmnU am{hbobo
nX H$mTy> eH$Vmo. g§~§Y doJdoJù¶m nÜXVrZo Xe©{dʶmMm Aä¶mg H$am.* n(A B) = n(A) + n(B) n(A B)
* n(A B) = n(A) + n(B) n(A B)
* n(A) = n(A B) + n(A B) n(B)
* n(B) = n(A B) + n(A B) n(A)
ho g§~§Y VH$m©Zo gwÜXm {gÜX H$aVm ¶oVmV.H$moU˶mhr A Am{U B, ¶m XmoZ gQ>mgmR>r n(A B) = n(A) + n(B) – n(A B)ho {gÜX hmoVmo.
A Am{U B gQ> doZ AmH¥$VrZo Xe©{dʶmMm {dMma H$am.
A B
A\B B\A
A B
ho ñnï> Amho H$s, A B hm A \ B, B \ AAm{U A B ¶m§Mm g§¶moJ Amho.
n(A B) = n(A \ B) + n(A B) + n(B \ A)
COì¶m ~mOy‘ܶo n(A B) {‘idyZ dOm Ho$bo AgVm, Vwåhmbm {‘iVo.
n(A B) = n(A \ B) + n(A B) + n(B \ A) + n(A B) – n(A B)
JQ> H$éZ,
n(A B) = [n(A \ B) + n(A B)] + [n(B \ A) + n(A B)] – n(A B)
Amnë¶mbm ‘m{hV Amho H$s, n(A \ B) + n(A B) = n(A) Am{U
n(B \ A) + n(A B) = n(B)
¶m qH$‘Vr dmnéZ, Amåhmbm {‘iob.
n(A B) = n(A) + n(B) – n(A B)
{Q>n: Oa A Am{U B ho Ag§~§YrV gQ> AmhoV Va, A B = Am{U n(A B) = 0
n(A B) = n(A) + n(B)
¶mdéZ AmnU Agm {ZîH$f© H$mTy> H$s,
AmR>dm: A\B hm XmoZ gQ>mVrb’$$aH$ Amho OoWo x A
Am{U x A
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Sets 13
åhUyZ JQ>m‘ܶo 100 {dÚmWu AmhoV.
darb CXmhaU doZ AmH¥$Vr dmnéZ gwÜXm gmoS>{dVm ¶oVo. Imbrb doZ AmH¥$VrMm Aä¶mg H$am. ˶m‘ܶo XmoZ
N>oXUmar dVw©io AmhoV, à˶oH$s EH$ dVw©io Xe©{dVmV. à˶oH$ {df¶mVrb {dÚm϶mªMr g§»¶m hr XmI{dë¶mà‘mUo
H$mT>Vm ¶oVo.
hm {ZH$mb Imbrb à‘mUo Vnmgbm OmVmo.
JQ>mVrb EHy$U {dÚm϶mªMr g§»¶m.
= 30 + 45 + 25 = 100
CXmhaU 3: Jmdm§Vrb 520 gXñ¶m‘ܶo, 360 gXñ¶ OZmdao nmiʶmV Jw§Vbobo AmhoV
Am{U 280 gXñ¶ Hw$ŠHw$Q>nmbZ Am{U 180 OU ì¶dgm¶ H$aVmV. Va {H$Vr gXñ¶
i)H$moU˶mhr H$m¶m©V Jw§Vbobo ZmhrV. ii) {H$Vr OU ’$³V Hw$Hw$Q >nmbZm‘ܶo Jw§Vbobo
AmhoV?
Sol: OZmdao nmiUmao, n(A) = 360 Hw$ŠHw$Q> nmbZ H$aUmao n(B) = 280
XmoÝhr H$aUmao n(A B) = 180
Amåhmbm _m{hV Amho H$mo, n(A B) = n(A) + n(B) – n(A B)
n(A B) = 360 + 280 – 180
n(A B) = 360 + 100 = 460
H$m¶m©V Jw§Vboë¶m gXñ¶m§Mr g§»¶m Amho. 460.
(i) H$moU˶mhr H$m¶m©V Z Jw§Vboë¶m gXñ¶m§Mr g§»¶m = 520 – 460 = 60.
60 gXñ¶ H$moU˶mhr H$m¶m©V Jw§Vbobo ZmhrV.
(ii) \$ŠV Hw$ŠHw$Q>nmbZm_Ü o Jw§Vboë`m bmoH$mMr g§»`m = n(B) \ n (A B)
= 280 – 180 = 100
doZAmH¥$VrZo darb CXmhaU Xe©{dVm oVoo
(iii) H$moUË`mM H$m_mV Z Jw§Vboë`m bmoH$m§Mr g§»`m
= 520 (180 + 180 + 100)
= 520 (460) = 60
K SU
360-180=180 =100
520-(180+180+100)=60
280-180
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Sets 15
Properties ofCardinality of sets
De Morgan's
Commutative Associative Distributive
I Law II Law
Disjoint setsn(A B) =
Union of sets Intersectionof sets A B
Union of sets Intersection of sets
gQ>
gQ>mdarb {H«$`m§MoJwUY_©
S>r- _m°J©Ýg {Z`_ gQ>m§Mr àm_w»`V:Cordindity of Sets
gmhM`© JwUY_©
H«$_{danoj JwUY_©
{dVaU JwUY_©
g§~§{YV gQ>n(A B) =
n (A) +n (B)
Ag§~§{YV gQ>n(A B) =n (A) +n
(B)-n (A B)
gQ>m§Mm g§ moJA B = A B
gQ>m§Moo N>oXZ A B =B
I {Z`_ (A B)1= A1 B1
II {Z`_ (A B)1= A1 B1
gQ>m§Mm g§ moJA B C) =(A B) C
gQ>m§Mm N>oXZA B C) =(A B) C
CÎmao
ñdmܶm¶ 1.2I. 1) 12 2) (i) 39 (ii)11 3) 125 4) (i) 26 (ii) 18 (iii) 68 5)73.33%
II. 1) (i)20 (ii) 25 (iii) 36 2) 15
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* H«$‘* A§H$J{UVr H«$‘ Am{U loUr* JwUmH$ma ì¶ñV H«$‘* JwUmoÎma H«$‘ Am{U loUr* JwUmoÎma loUr Am{U A§H$J{UVr
loUrMr ~oarO* A§H$J{UVr, JwUmH$ma, ì¶ñV Am{U JwUmoÎma ‘ܶ.
2
{bZmS>m} {ngmZmo ~moJmobmo
[1170-1250, BQ>br]
* Vo {\$~moZmgråhUyZ AmoiIbo OmVmVVo g§»`mÀ`m H«$_mgmR>>r bmoH${n«¶ AmhoV
åhUyZ ˶m§Zm {’$~mooZmgr H«$‘ AgoåhUVmV. 0, 1, 1, 2, 3, 5,
8,...... ¶oWo H«$‘mVrb n«Ë¶oH$ nX ho˶mÀ¶m AJmoXaÀ¶m XmoZ g§»¶m§Mr ~oarOAmho. (n{hbo d 2 ao nX gmoSy>Z) amo‘Z
g§»¶mÀ¶m EodOr {h§Xÿ Aao{~H$g§»¶mÀ¶m dmnamÀ¶m àgmambm ˶m§Zr
‘XV Ho$br.
* ¶m KQ>H$m‘wio Vwåhmbm ¶m §Mo gwb^rH$aUhmoVo. * A.P. Mr ì¶m»¶m H$aʶmg.
* A.P. Mo gm‘mݶén {bhrʶmg.* A.P. Mo 'a', 'c.d', Am{U 'Tn' emoYʶmg.* ‘¶m©XrV A§H$J{UVr loUrMr ~oarO H$mT>ʶmMo gyÌ
aMʶmg.* ‘¶m©XrV A§H$J{UVr loUrMr ~oarO H$mT>ʶmg.* JwUmH$ma ì¶ñV (H.P)H«$‘mMr ì¶m»¶m H$aʶmg.* H.P. Mo gm‘mݶ én H$mT>ʶmg* JwUmoÎma H«$‘mMr ì¶m»¶m H$aʶmg.* G.P Mo gm‘mݶ én {bhrʶmg.* G.P. Mo gm‘mݶ JwUmoÎma {bhrʶmg.* ‘¶m©XrV / A‘¶m©XrV JwUmoÎma loUrMr ~oarO
H$mT>ʶmMo gyÌ aMʶmg.* ‘¶m©XrV /A‘¶m©XrV JwUmoÎma loUrMr ~oarO H$mT>ʶmg* A.P, G.P Am{U H.P. À¶m Cn¶moJmMr CXmhaUo
gmoS>{dʶmg.* A§H$J{UVr, JwUmoÎma Am{U JwUmH$ma ì¶ñV ‘ܶ
H$mT>ʶmg.* AM, GM Am{U HM. ‘Yrb g§~§Y ñWm{nV
H$aʶmg.
"Mathematicians have tried in vain to this day todiscover some order in the sequence of prime numbersand we have reason to believe that it is a mysteryinto which human mind will never penetrate."
- Leonard Euler.
H«$‘(Progressions )
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Progressions 17
¶oWo ~wÜXr~im chess. À¶m emoYmMr Hw$VwhbmMrJmoï> Amho Vr dmMm.
nagr¶mMm amOm ~wpÜX~i Ioim{df¶r A˶§V IwfPmbo hmoVo. ˶m§Zr hm Ioi emoYUmè¶m 춺$sbm H$moUVmhrnwañH$ma Úm¶bm V¶ma Pmbo. emoYboë¶m 춺$sZo ~wpÜX~iIoimÀ¶m n{hë¶m Mm¡H$moZm‘ܶo JhÿMm EH$ XmZm (Ymݶ)R>odʶmg gm§{JVbo, Xþgè¶m Mm¡agm‘ܶo 2 JhÿMo XmUoAm{U {Vgè¶m 4 Mm¡agm‘ܶo 4, ¶mà‘mUo R>odʶmggm§{JVbo.
emoYH$mMr ‘mJUr EH$X‘ gmYr ({dZ‘«) hmoVr. na§VwamOmbm Vr nyU© H$aVmZm ‘moR>r g‘ñ¶m Pmbr. H$m?
¶m g‘ñ¶oMo CÎma emoYʶmgmR>r, Vwåhmbm J{UVmÀ¶m H$m§hr ¶w³Ë¶m ‘mhrVr Agë¶m nm{hOoV.˶m§Mm AmnU Aä¶mg H$é¶m
H«$‘ (Sequence)
Vwåhmbm g§»¶oÀ¶m Z‘wݶm§Mm n[aM¶ Amho. Imbrb g§»¶m§À¶m gQ>mVrb nw{T>b g§»¶m emoYʶmMmà¶ËZ H$am.
(i) 1, 5, 9, 13, .......... (ii) 1000, 100, 10, 1, ......... ((iii 1, 4, 9, 16, ............
(iv) 0, 7, 26, 63......... (v) 74, 15, 20, 31, 82, .........
Vwåhmbm H$m¶ {XgyZ Ambo? n{hë¶m Mma KQ>Zo‘ܶo Vwåhr nwT>rb g§»¶m H$er emoYbr? VwåhmbmnmMì¶m KQ>Zo‘ܶo nwT>r>b A§H$ emoYUo e³¶ Pmbo Zmhr H$m?
˶mMo H$maU åhUOo n{hë¶m Mma KQ>Zo‘ܶo, nXo EH$m {d{eï> {Z¶‘mZo H«$‘mV ‘m§S>br AmhoV.{Z¶‘ g‘OyZ Kody¶m.
g§»¶m Z‘wZm {Z¶‘
(i) 1, 5, 9, 13, 17 1 + 4 = 5, 5 + 4 = 9, 9 + 4 = 13, 13 + 4 = 17 4 {‘i{dbo
(ii) 1000, 100, 10, 1, 110 1000 × 1
10 =100, 100 × 110 =10, 1
10 Zo JwUbo10 × 1
10 =1, 1 × 110 = 1
10
(iii) 1, 4, 9, 16, 25 12 = 1, 22 = 4, 32 = 9, 42 = 16, 52 = 25 Z¡g{J©H$ g§»`mMm
– 8 × 2 = – 16, –16 × 2 = – 32 dJ©(iv) 0, 7, 26, 63, 124 13 –1 = 0,23 –1 =7,33 –1=26, 43–1 = 63,53– 1= 124 Z¡g{J©H$ g§»`mMm
KZ dOm 1
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Progressions 18
H$m§hr {Z¶‘mZwgma Ho$boë¶m g§»¶m§À¶m ‘m§S>Urbm H«$‘ Ago åhUVmV.H«$‘mVrb à˶oH$ g§»¶obm H«$‘mMr nXo Ago åhUVmV.
2, 5, 8, 11, .........¶m H«$‘m‘ܶon{hbo nX 2
Xþgao nX 5
{Vgao nX 8
ndo nXH«$‘m‘Yrb à˶oH$ nX {MÝhmZo Xe©{dVmV.
nXo n{hbo Xþgao {Vgao Mm¡Wo .... .... ndo .... ....
{MÝh T1 T2 T3 T4 .... .... Tn .... ....
H«$‘mMr nXo hr AmhoV, T1, T2, T3, T4, .............Tn..........
¶oWo, 'n' H«$‘mVrb nXm§Mr pñWVr (ñWmZ) Xe©{dVo.
‘¶m©XrV H«$‘ Am{U A‘¶m©XrV H«$‘ [Finite sequence and infinite sequence]
H«$‘mVrb nXo ‘moOVm ¶oV AgVrb Va ˶mbm ‘¶m©XrV H«$‘ Ago åhUVmV.
CXm :1) 2, 4, 6, 8, 10, 12, 14, 16, 18, 20
2) A = {x : x hm 5 ˦m nQ>rVrb Amho, 1 x 30}
‘¶m©{XV H«$‘mMo gm‘mݶ én, T1, T2, T3, T4, ............. Tn.
H«$‘mVrb nXo ‘moOVm ¶oV ZgVrb Va ˶mbm A‘¶m©{XV H«$‘ åhUVmV.CXm: 1) 1, 5, 9, 13, 17, .......... 2) B = {x : x < 0}
A‘¶m©{XV H«$‘mMo gm‘mݶ én, T1, T2, T3, T4, ..........
H«$‘ hr EH$ J{UVr g§H$ënZm Amho Á¶mMm Cn¶moJ AZoH$ X¡Z§{XZ OrdZmVrb KQ>Zm‘ܶo hmoVmo.{Z˶ OrdZmVrb KQ>Zm§À¶m H«$‘mMr H$mhr CXmhaUo Imbrb à‘mUo {Xbobr AmhoV.1) A‘¥VmZo à˶oH$ ‘{hݶmbm n¡em§Mr ~MV H$am¶bm gwadmV Ho$br. {VZo n{hë¶m ‘{hݶmV <50
Mr ~MV Ho$br, Xþgè¶m ‘{hݶmV <60, {Vgè¶m ‘{hݶmV <70 B.{VMr ~MV H«$‘m‘ܶo Aer 춺$ H$aVmV H$s,
50, 60, 70, 80,.....2. VéU Am°{’$gbm OmʶmgmR>r [ajmV ~gbm. ˶mZo ‘rQ>aMo [aS>tJ nm{hbo. Vo <20 hmoVo.
˶mZ§Va à˶oH$ 100 ‘r. À¶m àdmgmZ§Va 1< Zo dmT> Pmbr. Va ‘rQ>aMo [aS>tJ (Zm|X).
20, 21, 22, 23, ........
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Progressions 19
3 OrdmUy§À¶m H¥${Ì‘ dmT> H|$Ðm (laboratory) ‘ܶo, OrdmUy§Mr g§»¶m à˶oH$ Vmgmbm XwwßnQ> PmbobrAmT>iyZ Ambr. Oa gwadmVrbm VoWo 50 {OdmUy hmoVo, Va ˶m§Mr EHo$H$ VmgmZo g§»¶m Aer dmT>br H$s,50,100, 200,400.........4. EH$m {H$aUmoËgO©H$ ‘wbÐì¶mMm AY©OrdZ H$mi 12 Vmg Amho. Oa {H$aUmoËgO©H$ ‘wbÐì¶mMmgwadmVrMm Z‘wZm 100 J«°‘ Agob Va à˶oH$s 12 VmgmZ§Va Z‘wZm Agm KQ>Vm o H$s ,100, 50, 25, 12.5, .........
ñnîQ>rH$aUmË_H$ CXmhaUo
1. n do nX 2n + 3 $AgUmè`m H«$_m§Mr n{hbr VrZ nXo H$mT>m.
CH$b : oWo Tn = 2n + 3
T1, emoYÊ`mgmR>r Tn = 2n + 3 _Ü`o n=1 ¿`m
T1= 2(1) + 3 = 2 + 3 = 5
T2, emoYÊ`mgmR>r> n = 2 _Ü` Tn = 2n + 3 _Ü`o n=1 ¿`m
T2 = 2(2) + 3 = 4 + 3 = 7
VgoM T3 = 2(3) + 3 = 6 + 3 = 9
H«$_mMr n{hbr VrZ nXo VgoM 5, 7, 9. hr AmhoV
2. n do nX2
1n
n AgUmè`m H«$_mMr n{hbr 4 nXo H$mT>m.
CH$b : Tn =2
1n
n
T1 =21 1
1 1 2, T2 =
22 42 1 3
, T3 =23 9
3 1 4=
+, T4 =
24 164 1 5
=+
H«$_mMr n{hbr Mma nXo1 4 9 16, , , .2 3 4 5 hr AmhoV
3. Oa Tn = 3n – 10 Va H«$_mMo 20 do nXo H$mT>m.
CH$b : Tn = 3n – 10
T20 = 3(20) – 10 = 60 – 10 T20 = 50
4. Oa Tn = 5n + 2, Va Tn + 1 H$mT>m.
CH$b: Tn = 5n + 2
Tn + 1 = 5(n + 1) + 2 = 5n + 5 + 2 Tn + 1 = 5n + 7
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Progressions 20
5. Oa Tn = n3 – 1 Va Tn = 26. AgVmZm 'n' Mr qH$_V H$mT>m
CH$b: Tn = n3 – 1
26 = n3 – 1, n3 = 26 + 1 = 27, n = 3 27 n = 3
ñdmÜ`m` 2.1
1. Im{bbn¡H$s H$moUVo H«$_ AmhoV ?
(i) 4, 11, 18, 25, ..... (ii) 43, 32, 21, 10, ......
(iii) 27, 19, 40, 70, ...... (iv) 7, 21, 63, 189, ......
2. Imbrb H«$_mMr nwT>rb XmoZ nXo {bhm.
(i) 13, 15, 17, ____, _____ (ii)2 3 4, , , ___,___3 4 5
(iii) 1, 0.1, 0.01, ___, _____ (iv) 6, 12, 24, ____, ___
3. Oa Tn = 5 – 4n, Va n{hbr VrZ nXo H$mT>m
4. Oa Tn = 2n2 + 5, Va (i) T3 Am{U (ii) T10 H$mT>m
5. Oa Tn = n2 – 1, Va (i) Tn – 1 Am{U (ii) Tn + 1 H$mT>m
6. Oa Tn = n2 + 4 Am{U Tn = 200, Va 'n' Mr {H$_V H$mT>m.
A§H$J{UVr H«$‘ (Arithmetic progression)
¶ooWo H$m§hr H«$‘ AmhoV. ˶m§Mo {ZarjU H$am.
H«$‘ T2 – T1 T3 – T2 T4 – T3
5, 8, 11, 14, ..... 3 3 33, 13, 23, 33, .... 10 10 101, -1, –3, –5,... –2 –2 –21, 1.5, 2, 2.5, .... 0.5 0.5 0.5
darb H«$‘ XmoZ g‘mB©H$ ~m~tMo à{VnmXZ H$aVmV.
1. à˶oH$ H«$‘ ghOnUo ¶oUmè¶m g§»¶onmgyZ gwé hmoVmo. 2. ¶mXrVrb nwT>rb g§»¶m hr ˶mÀ¶m ‘mJrb g§»¶oV g‘mZ g§»¶m {‘i{dʶmZo ¶oVo.H«$‘mVrb H«$‘dma nXo g‘mZ (gma»¶mM) g§»¶oZo EH$Va H$‘r qH$dm dmT>V AgVrb Va ˶mbmA§H$J{UVr H«$‘ åhUVmV.Vo WmoS>³¶mV A.P. Ago {bhrVmV.A§H$J{UVr H«$‘ hm Agm H«$‘ Amho H$s Á¶m‘ܶo à˶oH$ nw{T>b nX ho ‘mJrb nXm‘ܶo(n{hbo nX gmoSy>Z) R>am{dH$ g§»¶m {‘i{dë¶mZo {‘iVo.
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Progressions 21
A.P, ‘ܶo à˶oH$ nX Am{U ˶mnwTr>b nX ¶m‘Yrb ’$aH$ pñWa AgVmo. ˶mbm gm‘mݶ ’$aH$ AgoåhUVmV.Vo WmoS>³¶mV c.d.. Ago {bhrVmV. Am{U Vmo 'd' Zo Xe©{dVmV. A.P, ‘ܶo gmYmaU ’$aH$ hm EH$Va YZ g§»¶m. F$Ug§»¶m qH$dm eyݶ ¶mn¡H$s AgVo.Oa T1, T2, T3, T4,....... hr A.P ‘Yrb nXo AmhoV.d = T2 – T1 = T3 – T2 = T4 – T3 = ................. = pñWa
{Q>n: A§H$J{UVr H«$‘m‘ܶo gmYmaU ’$aH$ eyݶ Agob Va ˶mbm A§H$J{UVr pñWa H«$‘ åhUVmV.CXm : 11, 11, 11, 11, ......... ½, ½, ½, ½, .........
¶oWo A§H$J{UVr H«$‘mMm g‘mdoe Agboë¶m H$m§hr KQ>Zm AmhoV.(i) B‘maVrÀ¶m darb mJmbm a§J bmdʶmgmR>r amOy {eS>rda 12 ’y$Q> C§Mrda
C^m Amho. Amnbo H$m‘ nyU© Pmë¶mZ§Va Vmo {eS>rdéZ Imbr CVaVmo, ˶m à˶oH$doir
˶mMo O‘rZrnmgyZMo A§Va 1.5 ’y$Q>mZo H$‘r hmoV OmVo. Va ˶mMo O{‘ZrnmgyZMoA§Va, 12 ’y$Q>, 10.5 ’y$Q>, 9 ’y$Q>, 7.5 ’y$Q>,.....
¶m KQ>ZoV, Vwåhr nm{hbo Amho H$s XmoZ H«$‘dma nXm‘Yrb ’$aH$ 1.5 Amho.
åhUyZ hm H«$‘ A.P. Amho.(ii) ‘wbo Pmonmù¶mda IoiV AmhoV. Ooìhm Vo PmoH$m KoVmV Voìhm gwadmVrÀ¶m ñWmZmnmgyZ
OmñVrV OmñV 50 g|.‘r. A§Vamda nmohmoMVmV. nmR>monmR> Am§XmobZm‘ܶo, à˶oH$
Am§XmobZmVrb A§Va 2 g|.‘r. Zo H$‘r hmoVo. åhUyZ à˶oH$ A§mXmobZmÀ¶mdoir AmH«${‘boboA§Va, 50, 48, 46, 44, .......
¶oWo gwÜXm Vwåhr nm{hbo Amho H$s XmoZ H«$‘dma g§»¶m‘Yrb gmYmaU ’$aH$ -2 Amho.åhUyZ hm H«$‘ A.P Amho.˶mMà‘mUo, AmnU nmZ 4 da MMm© Ho$bobr KQ>Zm gwÜXm A.P. Xe©{dVo.A‘¥VmMr ~MV, 50, 60, 70, 80, ..... Amho.¶oWo AmnU nmhVmo H$s gmYmaU ’$aH$ 10 Amho.
darb H«$‘ hm A.P. Amho.VéU Zo nm{hboë¶m ‘rQ>a‘Yrb Zm|Xr 20, 21, 22, 23....... AmhoV.¶oWo gmYmaU ’$aH$ 1 Amho.darb H«$‘ hm A.P Amho.
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Progressions 22
darb CXmhaUmdéZ ho CKS> Amho H$s, A.P ‘ܶo H$moU˶mhr nXm‘ܶo {ZpíMV g§»¶m åhUOoM gmYmaU’$aH$ {‘i{dbm AgVm nwT>rb nX {‘iVo.Oa 'a' ho n{hbo nX Am{U 'd' hm gmYmaU ’$aH$ Amho, Va
T1 = a
T2 = T1 + d = a + d
T3 = T2 + d = a + d + d = a + 2d
T4 = T3 + d = a + d + d + d = a + 3d Am{U B˶mXr.n{hbo nX 'a' gmYmaU ’$aH$ 'd' Agboë¶m A.P Mm gmYmaU Z‘wZm
a, a + d, a + 2d, a + 3d,..........
‘¶m©{XV Am{U A‘¶m©{XV A.P ( Finite & Infinite A.P) A§H$J{UVr H«$‘
A.P ‘Yrb nXm§Mr g§»¶m ‘moOVm ¶oV Agob Va ˶mbm ‘¶m©{XV A§H$J{UVr H«$‘ Ago åhUVmV.:CXm :1>) 6, 12, 18, 24, 30. 2>) 1, 2, 3, 4, 5, 6, 7, 8, 9, 10.
A.P ‘Yrb nXm§Mr g§»¶m ‘moOVm ¶oV Zgob Va ˶mbm A‘¶m©{XV A§H$J{UVr H«$‘ Ago åhUVmV.CXm :1>) 3, 7, 11, 15, ....... 2>) 10, 8, 6, 4, 2, 0, –2, .......
A.PMm gm‘mݶ Z‘wZm (General form of an A.P)
pñ‘VmZo ‘mMrgÀ¶m H$mS>çm§Mr ‘m§S>Ur H$éZ Mm¡agmH¥$Vr AmH$ma ~Z{dbo. n{hbm Mm¡ag 4 ‘m{MgÀ¶mH$mS>çmZr V¶ma hmoVmo. {VZo AmUIr 3 H$mS>çm {‘idyZ 2 am Mm¡ag ~Z{dbm Z§Va {VZo AmUIr VrZH$mS>çm {‘idyZ {Vgam Mm¡ag ~Z{dbm Am{U B.Imbr {Xboë¶m gmaUrMo {Z[ajU H$am.à˶oH$ KQ>Zo‘ܶo, V¶ma Pmboë¶m Mm¡agmMm AmH$ma XmI{dbm Amho.à˶oH$ KQ>ZoV dmnaboë¶m H$mS>çm Am{U g§»¶m§Mr ‘m§S>Ur {Vgè¶m Am{U Mm¡Ï¶m ñV§ mV {Xbobr Amho.nmMì¶mñV§ mV V¶ma Pmboë¶m Mm¡agm§Mr g§»¶m {dMmamV KodyZ g§»¶mMr ‘m§S>Ur nwÝhm {bhrbobr Amho.Mm¡agm§Mr H$mS>çm§Mr g§»¶m ‘m§S>Ur Mm¡agmÀ¶m g§»¶oÀ¶mg§»¶m ñdénmV 춺$ H$aUo.
1. 4 4 4
2. 7 4 + 3 4 + 3(2 – 1)
3. 10 4 + 3 + 3 4 + 3(3 – 1)
4. 13 4 + 3 + 3 + 3 4 + 3(4 – 1)
n 4 + 3 (n – 1)
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Progressions 23
gmaUr déZ AmnU Agm {ZîH$f© H$mTy> H$s,(i) 4, 7, 10, 13..... ho A.P ‘ܶo AmhoV.
(ii) n{hbo nX 4 Amho i.e., a = 4(iii) gmYmaU ’$aH$ 3 Amho i.e., d = 3(iv) Oa VoWo 'n' Mm¡ag AmhoV, Va V¶ma Pmbobr ‘m§S>Ur 4 + 3(n – 1)(v) Va n do nX, a + d (n – 1) qH$dm Tn = a + d (n – 1)
A.P ‘ܶo, Oa n{hbo nX 'a' gmYmaU ’$aH$ 'd' Agob Va n do nX H$mT>ʶmMo gyÌ Tn = a + (n – 1)dCXmhaU 1 : 2, 6, 10, 14, .......¶m A.P Mm {dMma H$am.¶oWo T1 = a = 2, d = T2 – T1 = 6 – 2 = 4T1 = 2 = a = a + (1 – 1)dT2 = 6 = 2 + 4 = a + d = a + (2 – 1)dT3 = 10 = 2 + 4 + 4 = a + d + d = a + (3 – 1)dT4 = 16 = 2 + 4 + 4 + 4 = a + d + d + d = a + (4 – 1) d
Tn = a + d + d......+ (n – 1) doim = a + (n – 1)d
Tn = a + (n – 1) d
darb CXmhaUmdéZ AmnU Agm {ZîH$f© H$mTy> H$s,n{hbo nX 'a' gmYmaU ’$aH$ 'd' Agboë¶m A.P Mm gm‘mݶ Z‘wZm, a, a + d, a + 2d,..............., a + (n – 1)d,......AmhoA.P Mo gm‘mݶ nX Tn = a + (n – 1)dCXmhaU 2 : 3, 4, 5, 6,.....¶m H«$‘mMo 1000 do nX emoYm.H«$‘m‘ܶo, ‘mJrb nXm‘ܶo 1 {‘i{dbo AgVm nwTr>b nX {‘iVo.
hr nÜXV dmnéZ 1000do nX H$mT>VmZm, Amnë¶mbm 1000 nXo {bhmdr bmJVmV. hr nÜXV doiH$mTy> Am{U H§$Q>midmUr Amho.
Oa ¶m H«$‘mMo gm‘mݶ nX aMbo, Va H$moUVohr hdo Agbobo nX ghOnUo H$mT>Vm ¶oVo.
¶m H«$‘m‘ܶo gmYmaU ’$aH$ (c.d) 1 Amho.1bo nX T1 = 3 = 3 + 0(1) 2 ao nX T2 = 4 = 3 + 1 = 3 + 1(1)3 ao T3 = 5 = 3 + 1 + 1 = 3 + 2(1)
ndo nX Tn = 3 + 1 + 1 + ....(n – 1) doim = 3 + (n – 1)(1)= 3 + n – 1 = 2 + n
Tn = 2 + n
1000do nX = T1000 = 2 + 1000 = 1002
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Progressions 24
Ogo AmVmM AmnU A.P Mo n do nX emoYbo. AmnU A.P. ‘ܶo Zgboë¶m H$m§hr H«$‘mMo ndo nX
gwÜXm H$mTy> eH$Vmo.
CXmhaU 3 :
1) 2, 4, 6, 8, .........¶m H«$‘mMo ndo nX H$mT>m., 2) ¶m H«$‘mMo ndo nX H$mT>m.1 2 3, , ,......2 3 4
T1 = 2 = 2 × 1 T1 =12 =
11 1
T2 = 4 = 2 × 2 T2 =23
=2
2 1T3 = 6 = 2 × 3 T3 =
34
=3
3 1Tn = 2 × n
Tn = 2 × n Tn = 1n
n + Tn = 1
nn +
na§Vw gd© H«$‘m§Mo gm‘mݶ én H$mT>Uo e³¶ Zmhr.
{dMma H$am Am{U JQ> H$éZ MMm© H$am.
(i) 5, 17, 29, 31, 100, 450,....ho MT>˶m H«$‘mV {b{hbo na§Vw ¶mMo gm‘mݶ nX
H$mT>Uo Ae³¶ Amho. (ii) 2, 3, 5, 7, 11, ...... hm ‘yi g§»¶m§Mm H«$‘ Amho. ¶m H«$‘mMo
gm‘mݶ nX H$mT>Uo Ae³¶ Amho.
Amåhmbm ‘mhrV Amho H$s, A.P ‘ܶo gmYmaU ’$aH$ 'd'.Amho.
( (i) Tn + d = Tn + 1 ) ( (ii) Tn – d = Tn – 1)Imbrb H$moï>H$mMo {ZarjU H$am.
A.P ‘ܶo,
T2 = T1 + d T2 = T1 + (2 – 1)d T2 – T1 = (2 – 1)d d = 2 1
2 1T T
T3 = T1 + d + d T3= T1 + (3 – 1)d T3 – T1 = (3 – 1)d d = 3 1
3 1T T
T5 = T4 + d T5 = T4 + (5 – 4)d T5 – T4 = (5 – 4)d 5 4d5 4
T T
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Progressions 25
gm‘mݶnUo, p qT Td =
p q
Oa Tp = Tn Am{U Tq = T1(ie., a) Va darb g§~§Y
Tn 1n ad Agm {bhrbm OmVmo.
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1. 13, 19, 25, 31,....... ho A.P. ‘ܶo AmhoV H$m Vo Vnmgm.
CH$b : ¶oWo, T1 = 13, T2 = 19, T3 = 25, T4 = 31 Am{U B˶mXrd = T2 – T1 = 19 – 13 = 6d = T3 – T2 = 25 – 19 = 6d = T4 – T3 = 31 - 25 = 6
gmYmaU ’$aH$ pñWa Amho, {Xbobm H«$‘ A.P. ‘ܶo Amho.
CXmhaU 2. Oa a = 3 Am{U c.d = 4, Va A.P. emoYm.
CH$b: a = 3, c.d = 4 Am{U T1 = a = 3 qH$dm.T1 = a = 3T2 = a + d = 3 + 4 = 7 T2 = T1 + d = 3 + 4 = 7T3 = a + 2d = 3 + 2(4) = 3 + 8 = 11 T3 = T2 + d = 7 + 4 = 11T4 = a + 3d = 3 + 3(4) = 3 + 12 = 15 T4 = T3 + d = 11 + 4 = 153, 7, 11, 15, ......hr A.P Amho.
CXmhaU 3 : 12, 19, 26,......¶m A.P Mo Tn Am{U T15 nX H$mT>m.
CH$b : a = 12, d = 19 – 12 = 7, Tn = ?, T15 = ?
Tn = a + (n – 1)dTn = 12 + (n – 1)7 = 12 + 7n – 7Tn = 5 + 7n
g‘Om, Tn = 5 + 7n
T15 = 5 + 7(15) = 5 + 105T15 = 110
CXmhaU 4: 7, 13, 19, ........151 ¶m A.P ‘Yrb nXm§Mr g§»¶m H$mT>m.CH$b : a = 7, d = T2 – T1 = 13 – 7 = 6, Tn = 151, n = ?
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Progressions 26
Tn = a + (n – 1)d151 = 7 + (n – 1) 6 = 7 + 6n – 6151 = 1 + 6n 151 – 1 = 6n 150 = 6n
n =150
25
6 n = 25
CXmhaU 5: A.P Mo 8 do nX 17 Am{U 19 do nX 39 Amho. Va 25 do nX H$mT>m.CH$b : T8 = 17, T19 = 39, T25 = ?
T25, H$mT>ʶmgmR>r Amnë¶mbm 'a' Am{U 'd' H$mT>bo nm{hOo. n`m© r nÜXV
d =T Tp q
p q
d = 19 8T T19 8 =
39 1711 =
222
11 d = 2
g‘Om, T8 = 17
a + 7d = 17 [ Tn = a + (n – 1)d]a + 7(2) = 17
a + 14 = 17
a = 3
T25 , Tn = a + (n – 1)d H$mT>VmZm T25 = 3 + (25 – 1)2 = 3 + (24 × 2) = 3 + 48
T25 = 51
CXmhaU 6 : H« _mMo 4Wo nX 17 Am{U 10 do nX 7ì¶m nXmnojm 12Zo OmñV Amho Va A.PemoYm.
CH$b : T4 = 17, T10 = T7 + 12
a + 9d = a + 6d + 12
3d = 12
d = 4
T4 =a + 3d 17 a + 12
a =17 – 12a = 5
5, 5 + 4, 5 + 2(4),......hr Amho. 5, 9, 13, .....
T8 =a + 7d = 17 T19=a +18d = 39(a +18d) - (a +7d) = 39 - 17
11d = 22
d = 2T8 =a + 7× 2 = 17
a +14 = 17a =3
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Progressions 27
CXmhaU 7 : EH$m A.P ‘ܶo 7ì¶m nXmMr 7 nQ> hr 11ì¶m nXmÀ¶m 11 nQ>r BVH$s Amho VaA.P Mo 18 do nX H$mT>m.
CH$b : 7 × T7 = 11 × T11
7(a + 6d) = 11(a + 10d)
7a + 42d = 11a + 110d
7a – 11a = 110d – 42d
–4a = 68d a =684
d
a = – 17d
g‘Om, T18 = a + 17d
= – 17d + 17d
T18 = 0
ñdmܶm¶ 2.2
1. Imbrb A.P Mr nwT>rb Mma nXo {bhm.(i) 0, –3, –6, –9, ___, ___, ___, ___,
(ii)1 1 1, , ,6 3 2 ___, ___, ___, ___,
2. H«$‘ H$mT>m Oa,(i) Tn = 2n – 1
3. A.P ‘ܶo,(i) Oa a = -7, d =5, Va T12 H$mT>m. (ii) a = -1, d = –3 , VaT50 H$mT>m.
(iii) Oa a = 12, d = 4, Tn = 76, Va n H$mT>m. (iv) Oa a =12, d = –2, T22= –39, Va a H$mT>m.(v) Oa a = 13, T15 = 55, Va 'd' H$mT>m.
4. 100, 96, 92, ......., 12.¶m A.P ‘Yrb nXm§Mr g§»¶m H$mT>m.5. {ÌH$moUmMo H$moZ A.P ‘ܶo AmhoV. Oa bhmZ H$moZ 500 Amho Va BVa XmoZ H$moZ emoYm.6. EH$m A.P ‘ܶo 50 nXo AmhoV, ˶mMo {Vgao nX 12 Am{U eodQ>Mo nX 106 Amho Va 29
do nX H$mT>m.7. A.P ‘Yrb 4϶m Am{U 8 ì¶m nXm§Mr ~oarO 24 Am{U ˶mM H«$‘mÀ¶m 6ì¶m Am{U 10
ì¶m nXm§Mr ~oarO 44 Amho. Va n{hbr VrZ nXo H$mT>m.8 EH$m A.P À¶m 7 ì¶m d 3è¶m nXm§Mo JwUmoÎma 12:5 Va 13ì¶m d 4϶m nXm§Mo JwUmoÎma
H$mT>m.
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Progressions 28
9. EH$m H§$nZrZo 2001 ‘ܶo 400 춺$s¨Zm H$m‘ {Xbo Am{U à˶oH$ dfu 35 춺$s¨Mrg§»¶m dmT>{dbr. Va H$moU˶m dfu H§$nZrV H$m‘Jmam§Mr g§»¶m 785 hmoB©b.?
10. Oa EH$m A.P Mo p do nX q Am{U q do nX p Amho Va ndo nX (p + q – n) Amho ho {gÜXH$am.
11. A.P À¶m Xþgè¶m Am{U {Vgè¶m nXm§Mr ~oarO 22 Am{U n{hë¶m d 4϶m nXm§MmJwUmH$ma 85 Amho. Va A.P Mr Mma nXo H$mT>m.
H«$_mVrb nXm§Mr ~oarO (Sum to n terms of a sequenec)
AOw©ZZo JmoQ>çm§Mr ‘m§S>Ur Imbr XmI{dë¶mà‘mUo Ho$br.Am{U BVa (B˶mXr)
Oa ˶mZo hr ‘m§S>Ur (Z‘wZm) AmUIr 10 nm¶è¶mV Ho$br.
AOw©ZZo ‘m§S>Ur Ho$boë¶m EHy$U JmoQ>çm§Mr g§»¶m {H$Vr?¶m CXmhaUmMo CÎma emoYʶmgmR>r, Amåhmbm à˶oH$ JQ>mVrb JmoQ>çm§Mr g§»¶m H$mT>mdr bmJob.Oa T1 + T2 + T3 + ...... + Tn hm H«$‘ Amho. Va T1 + T2 + T3 + ...... + Tn À¶m ~oaOobm {Xboë¶m H«$‘mVrb
nXm§Mr ~oarO Ago åhUVmV. Vr 'Sn' Zo Xe©{dVmV.Sn = T1 + T2 + T3 + ...........+Tn
Oa T1 + T2 + T3 + ...... + Tn hm H«$‘ Amho. Va T1 + T2 + T3 + ...... + Tn amerbm loUr åhUVmV.
{Q>n: S1 = T1 S2 = T1 + T2 S3 = T1 + T2 + T3 Am{U BVa
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1.Oa Tn = 2n – 1 Va S3H$mT>m. CXmhaU 2. Oa Tn = n2 + 1, Va S2 H$mT>m.
CH$b : S3 = T1 + T2 + T3 CH$b : S2 = T1 + T2
Tn = 2n – 1 Tn = n2 + 1
T1 = 2(1) – 1 = 2 – 1 = 1 T1 = 12 + 1 = 1 + 1 = 2
T2 = 2(2) – 1 = 4 – 1 = 3 T2 = 22 + 1 = 4 + 1 = 5
T3 = 2(3) – 1 = 6 – 1 = 5 S2 = T1 + T2
S3 = T1 + T2 + T3 = 1 + 3 + 5 S2 = 2 + 5
S3 = 9 S2 = 7
A.P Mo 'n' do nX Am{U n ì¶m nXm§ n¶ªVMr ~oarO ¶m‘Yrb g§~§Y.g‘Om,Tn = 5n – 2
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Progressions 29
T1 = 5(1) – 2 = 5 – 2 = 3
T2 = 5(2) – 2 = 10 – 2 = 8
T3 = 5(3) – 2 = 15 – 2 = 13
T4 = 5(4) – 2 = 20 – 2 = 18
T5 = 5(5) – 2 = 25 – 2 = 23
nmhm H$s,S2 – S1 = 11 – 3 = 8 = T2S3 – S2 = 24 – 11 = 13 = T3S4 – S3 = 42 – 24 = 18 = T4S5 – S4 = 65 – 42 = 23 = T5
Sn – Sn – 1 = Tn
A§H$J{UVr loUr (Arithmetic series)
A§H$J{UVr H«$‘mVrb nXo loUr ‘ܶo AgVrb Va ˶mbm A§H$J{UVr loUr Ago åhUVmV.
CXm: 2 + 4 + 6 + 8 + 10 = 30 1 + 5 + 9 + 13 + 17 + 20 = 66
{Q>n : A‘¶m©{XV A§H$J{UVr loUrMr ~oarOH$mT>Uo Ae³¶ Amho.
A.P À¶m 'n' nXm§Mr ~oarO [Sum of first 'n' terms of an A.P]
~oaOoMm Ioi Ioiy¶m Ago g‘Oy. Imbrb loUrMr ~oarO H$mT>m.1 + 22 + 5 + 84 + 7 + 10 + 13 + 16_1 + 3 + 5 + 7 + ....... + 101
H$moU˶m KQ>Zo‘ܶo Vwåhr ~oarO ghOnUo H$mT>mb? H$m? MMm© H$am.darb CXmhaUmdéZ, Amåhmbm Ago g‘OVo H$s, Oa A.P ‘Yrb nXm§Mr g§»¶m bhmZ Agob Va AmnU˶mMr ~oarO ghOnUo H$éZ ~oarO {‘idy eH$Vmo. na§Vw nXm§Mr ~oarO ‘moR>r Agob Va Amnë¶mbm H$R>rUOmVo Am{U OmñV doi bmJVmo.
ObXnUo Am{U ghOnUo ~oarO H$mT>Vm ¶oʶmMr H$moUVrhr gmonr nÜXV Amho H$m?¶oWo J{UVrÀ¶m B{VhmgmVrb EH$ Hw$VwhbmMm àg§J Amho.JmoîQ>rMr gwédmV Aer Pmbr. H$mb© ’|$S>rM Jm°g hm ‘wbJm ImoS>H$a hmoVm Am{U {ejH$m§Zr {Xbob§
CXmhaU ËdarV gmoS>dm¶Mm.EH$ {Xdg {ejH$m§Zr ˶mbm 100 n¶ªVÀ¶m Z¡g{J©H$ g§»¶m§Mr ~oarO H$am¶bm gm§{JVbr Am{U
S1 = T1 = 3S2 = T1 + T2 = 3 + 8 = 11S3 = T1 + T2 + T3 = 3 + 8 + 13 = 24S4 = T1 + T2 + T3 + T4 = 3 + 8 + 13 +18 = 42S5 = T1 + T2 + T3 + T4 + T5 = 3 + 8 + 13 + 18 + 23 = 65
darb CXmhaUmdéZ, AmnU Agm {ZîH$f© H$mTy> H$s,S2 – S1 = T2S3 – S2 = T3S4 – S3 = T4S5 – S4 = T5
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Progressions 30
˶mbm H$m‘mV Jw§VdʶmMm à¶ËZ Ho$bm. na§Vw Jm°gZo H$mhr doimVM ~oarO 5050 ¶oVo Ago CÎma {Xbo.AmVm AmnU AJXr ghOnUo CÎma H$go H$mT>bo Vo nmhÿ¶m.˶mZo hr ~oarO Aer {bhrbr H$s,
S100 = 1 + 2 + 3 + 4 + .......... + 100
S100 = 100 + 99 + 98 + ........ + 2 + 1 (CbQ> H$éZ)
2S = 101 +101 + 101 +....................... + 101 (~oarO H$éZ)
2S = 101 × 100 [ 101 ho 100 doim {‘i{dbobo Amho]
S =101 100´
50
2S100 = 5050
AmnU VoM V§Ì dmnéZ A.P À¶m 'n' nXm§Mr ~oarO H$mTy> eH$Vmo.Oa A.P Mo 'a' ho n{hbo nX d 'd' hm gmYmaU ’$aH$ Am{U Sn hr A.P. À¶m 'n' nXm§Mr ~oarO Xe©{dVo.Va
Sn = T1 + T2 + T3 + ......... + TnSn = a + (a + d) + (a + 2d) + .......... + [a + (n– 1)d].
Sn = [a +(n – 1)d] + [a + (n – 2)d] +................................... + a (CbQ >H$éZ)
2Sn =[2a + (n – 1)d] + [2a + (n – 1)d] + ..........................................+[2a + (n – 1)d] (~oarOH$éZ)
2Sn =[2a + (n – 1)d] × n [ 2a + (n – 1)d] bm 'n' doim {‘idy. )
[ ]+ -nn
S 2 a (n 1 )d2
{Q>n : Oa 1 + 2 + 3 + 4 + ...........+n, hr A.P n{hë¶m 'n' (Z¡g{J©H$ g§»¶m§Mr ~oarO) Amho.¶oWo, a = 1, d = T2 – T1 = 2 – 1 = 1, n = n
Sn = 2 ( 1)2n a n d
H$mb© ’«|$S´>rM Jm°g [1777-1855, O‘©Zr] hm J{UVmMm amOHw$‘ma Amho ˶m§ZrAmnbr JUUoMr eº$s A˶§V ~mbnUr d¶mÀ¶m 3è¶m dfu àX{e©V Ho$br. ˶m§Zrd¶mÀ¶m 24ì¶m dfu e³¶Vmo AmVmn¶ªVMo J{UVmVrb ewÜX nwñVH$ g§»¶memómMoAm¡nMmarH$ boI à{gÜX Ho$bo. ¶wp³bS>À¶m A§H$J{UVm‘Yrb ‘yb yV à‘o¶mMrg§nyU© {gÜXVm H$aUmao Vo n{hbo AmhoV.
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Progressions 31
Sn = 2.1 ( 1)12n n = 2 1
2n n
( 1)2n
n nS qH$dm n(n +1)n =2
n{hë¶m 'n' Z¡g{J©H$ g§»¶m§Mr ~oarO =( 1)
2n n
{Q>n : Amnë¶mbm ‘m{hV Amho H$s, Sn = [2 ( 1) ]2n a n d
ho Agohr {bhrbo OmVo H$s, Sn = ( 1)2n a a n d
n nnS = a + T2 [ Tn = a + (n – 1)d]
¶oWo, a n{hbo nX, Tn ndo nXT
2na hr A.P. À`m n{hë`m Am{U eodQ>À`m nXm§Mr gamgar Amho.
`mMm AW© A.P. À`m n{hë`m 'n' nXm§Mr ~oarO hr 'n' doim n{hbo Am{U eodQ>Mo nX m§Mr gamgar AmhoOa AmnU darb gyÌ n{hë¶m 'n' Z¡g{J©H$ g§»¶m§Mr ~oarO H$mT>ʶmgmR>r dmnabo OmVo.
ñnï>rH$aUmË‘H$ CXmhaUoCXmhaU 1: Oa Tn = 5n – 2, Va S4H$mT>m.CH$b : g‘Om,
Tn = 5n – 2T1 = 5(1) – 2 = 5 – 2 = 3 S4 = T1 + T2 + T3 + T4T2 = 5(2) – 2 = 10 – 2 = 8` S4 = 3 + 8 + 13 + 18T3 = 5(3) – 2 = 15 – 2 = 13 S4 = 42T4 = 5(4) – 2 = 20 – 2 = 18
CXmhaU 2 : 1 + 2 + 3 + ..... ¶m loUrÀ¶m n{hë¶m 20 nXm§Mr ~oarO H$mT>m.CH$b : {Xbobr loUr hr Z¡g{J©H$ g§»¶m§Mr Amho. åhUyZ AmnU g§~§Y dmnéZ ~oarO H$mTy>eH$Vmo.
n =( 1)
2n n + ¶oWo, n = 20
S20=20(20 1)
2+
S20 =20
1021
2S20 = 210
(AmnU {MÝh dmnéZ n Z¡g{J©H$ g§»¶m§Mr~oarO H$mTy> eH$Vmo. Vo Ago Xe©{dVmV.)
n
1
1 + 2 + 3 + ........+na = 1, Tn = n, n = nSn =
T2 nn a
Sn = 12n n =
( 1)2
n n n
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Progressions 32
CXmhaU 3 : 5, 8, 11, 14, ... ¶m A.P À¶m n{hë¶m 15 nXm§Mr ~oarO H$mT>m.
CH$b :a = 5, n = 15, c.d = 8 – 5 = 3
Sn = 2 ( 1)2n a n d
S15 =15 2(5) (15 1)32 =
15 10 (14)(3)2 S15 = 15
252´
26
S15 = 390 S15 = 390
CXmhaU 4 : 200 Am{U 300 ‘Yrb nyU©nUo 6 Zo ^mJ OmUmè¶m gd© Z¡g{J©H$ g§»¶m§Mr
~oarO H$mT>m.
CH$b :
204 + 210 + 216 + .......... + 294 hr A.P Amho.
a= 204, d = 210 – 204 = 6, Tn = 294, Sn = ?
Sn, H$mT>ʶmgmR>r àW‘ Amåhmbm 'n'Mr qH$‘V H$mT>mdr bmJob.
Tn = 294 'n' Mr qH$_V H$mT>Ê`mMr n`m© r nÜXV
a + (n – 1)d = 294 Tn=a + (n-1) d Mm {dMma H$am 'n' À`m ñdê$nmV Amho.
204 + (n – 1) 6= 294 gyÌ nwÝhm {bhm
204 + 6n – 6= 294T 1n an
d198 + 6n = 294 294 204
16
n-
\ = +90 16
6n= 294 – 198 = 96 n = 15 + 1 = 16
n = 96/6
n= 16
Sn = T2 nn a
S16 = [ ]16204 294
2+ =
168
2498
S16 = 3984
CXmhaU 5 : a‘oebm «‘U ¶§Ì (Mobile Phone) IaoXr H$amd¶mMm Amho. Vmo ˶mbm <15000 amoI^éZ qH$dm 12 g‘mZ ‘m{gH$ háo H$éZ n{hë¶m ‘{hݶmV < 1800 d Xþgè¶m ‘{hݶmV <1750,{Vgè¶m ‘{hݶmV < 1700 Am{U B. éZ IaoXr H$aVmo. Oa ˶m§Zo a¸$‘ hß˶m§Zr abr Va (i)12 hß˶m‘ܶo ^abobr EHy$U a¸$‘ (ii) amoI a¸$‘onojm ˶mbm {H$Vr OmñVrMr a¸$‘ ^amdrbmJob Vo H$mT>m.
à`ËZ H$am,Sn= n ( a +Tn)
hm g§~§Y dmnê$Z gmoS>dm
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Progressions 33
CH$b : ¶oWo,
1800 + 1750 + 1700 + ......hr A.P Amho.a = 1800, d = T2 – T1 = 1750 – 1800 = – 50, n = 12, S12 = ?
Sn = 2 ( 1)2n a n d
S12 =12
6
22(1800) (12 1) ( 50)
S12 = 6[3600 + 11(–50)] = 6[3600 – 550]S12 = 6 × 3050S12 = 18,300
12 hß˶m‘ܶo abobr EHy$U a¸$‘ = < 18,300
OmXm amdr bmJUmar a¸$‘ = 18,300 -15000 =3300
CXmhaU 6: A.P _Yrb n{hbo VrZ YZ nyUmªH$ H$mT>m Aem [aVrZo H$s Ë`m§Mr ~oarO 24 Am{U
JwUmH$ma 480 Amho.
CH$b: a-d, a, a+d hr VrZ nXo AmhoV Ago _m§Zy
~oarO =24
a - d + a + a + d = 24
3 a = 24
Oa a - d + a + a + d = 24
3 a = 24
a=8
Oa a = 8, d=2 Va H«$_mVrb nXo a - d = 8 - 2 = 6, a = 8, a+ d = 8 + 2 = 10
H«$_mVrb nXo 6,8,10 hr Amho
CXmhaU 7: A _Ü`mnmgyZ gwadmV H$ê$Z EH$mZ§Va EH$ gVV AY© dV©wio KoodyZ Ë`mMm _Ü` A Z§Va
B KodyZ doQ>moio ~Z{dbo Ë`m§Mr pÌÁ¶m AmH¥$VrV XmI{dë`m à_mUo 0.5 go. _r, 1go._r,1.5
go._r,2 go._r ......B Amho Va 13 H«$_dma AY©dVw©io OmoSy>Z ~Z{dboë`m doQ>moù`mMr bm§~r
H$mT>m? ( 22 ¿`m)
à`ËZ H$am: Ooìhm
a =8, d=2
Agob Va nXo H$mT>m
Vwåhmbm H$m` {XgyZ ooVo ?
JwUmH$ma =480
(a-d) a (a+d) =480
(8-d) 8(8+d)=480 ( a = 8)
(8-d) (8+d)=480/8=60
64-d2= 60
d2= 64 - 60
d=±2
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Progressions 34
r1 = 0.5 cm, r2 = 1cm, r3 = 1.5 cm,.......... `m {ÌÁ¶oÀ`m
AY©dVw©im§Mr bm§~r AZwH«$_o l1, l2 l3 Amho.
dV©wimMm n[aK = 2 r
AY©dVw©imMm n[aK = r
=l1 = r1 = × 0.5 =2
,l2 = r2 = × 1 = = 22
V©wimMm n[aK l13 = r13 =132 = 13
2
doQ>moù`mMr EHy$U bm§~r= l1 + l2 + ........ + l13
= 2 3 ..... 132 2 2 2 =
2[1 + 2 + 3 + .......+13] =
13
12n
=13(13 1)
2 2 =13 14
2
7
2 =
12
2211
713 7 = 143 g|.‘r.
ñdmܶm¶ 2.3
1. Oa Tn = 2n + 3, Va S3 H$mT>m.2. Imbrb loUtMr ~oarO H$mT>m.
(i) 3 + 7 + 11 + ........ 25 ì¶m nXmn¶ªV (ii) -3, 1, 5 ........ 17 ì¶m nXmn¶ªV(iii) 3a, a, -a ........ a ì¶m nXmn¶ªV (iv) p, o, -p ........ p ì¶m nXmn¶ªV
3. A.P À¶m 111 nXm§Mr ~oarO H$mT>m Á¶mMo 56 do nX 537Amho.
4. Z¡g{J©H$ g§»`mÀ`m H«$_mgmR>r a) (i) 20 (ii) S50 - S 40 (iii) S30+ S15 H$mT>m.
b) 'n' H$mT>m Oa (i) Sn= 55 (ii) Sn =15
5. n{hë¶m 'n' {df‘ Z¡g{J©H$ g§»¶m§Mr ~oarO H$mT>m.
6. 1 Am{U 201 ‘Yrb 5 Zo mJ OmUmè¶m gd© Z¡g{J©H$ g§»¶m§Mr ~oarO H$mT>m.
7. EH$m loUrÀ¶m n nXm§Mr ~oarO 1 7 -12
n n Agob Va n{hbr Mma nXo H$mT>m.
8. 1, 4, 7, ...... ¶m A.P ‘Yrb {H$Vr nXm§Mr ~oarO 51 hmoB©b?
9. AP ‘Yrb VrZ nXo H$mT>m. Oa ˶m§Mr ~oarO Am{U JwUmH$ma AZwH«$‘o (i) 21 Am{U 231(ii) 36 Am{U 1620 Amho.
l5 l3
l1
l2l4
A B
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Progressions 35
10.A.P À¶m 6 nXm§Mr ~oarO 345 Amho n{hë`m d eodQ>À`m nXm_Yrb \$aH$ 55 Amho Va Vr nXoH$mT>m .
(1/4) Amho. Va T20 = –112 ho XmIdm Am{U S20 H$mT>m.
11.EH$m AP Mo n{hbo nX 2 Amho, n{hë¶m nmM nXm§Mr ~oarO hr nwT>rb nmM nXm§À¶m EH$ MVwWmªe
(1/4) Amho. Va T20 = –112 ho XmIdm Am{U S20 H$mT>m.
12. EH$ A.P Mo {Vgao nX 8 Am{U A.P Mo 9 do nX ho 3è¶m nXmÀ¶m 3 nQ>rnojm 2 Zo A{YH$ Amho.
Va ˶mÀ¶m n{hë¶m 19 nXm§Mr ~oarO H$mT>m.
JwUmH$ma ì¶ñV H«$‘ [HARMONIC PROGRESSION]
Imbrb H$moï>H$mMo {ZarjU H$am.
H«$‘ ì¶ñV
1 1 1 1, , , ,......2 5 8 11
2, 5, 8, 11,.....
1 1 1 1, , , ,......30 28 26 24
30, 28, 26, 24, ......
2 2 21, , , ,......3 4 5
3 4 51, , , ,......2 2 2
Aem H«$_mbm JwUmH$ma ì`ñV H«$_ åhUVmV d Vmo WmoS>Š`mV H.P Ago {bhrVmVH«$‘mVrb à˶oH$ nXmMm JwUmH$ma ì¶ñV KoVë¶mg V¶ma hmoUmam H«$‘ A§H$J{UVr H«$‘Agob Va ˶mbm JwUmH$ma ì¶ñV H«$‘ Ago åhUVmV.
H.P Mo gm‘mݶ én [General form of H.P.]
Oa A.P Mo n{hbo nX 'a' Am{U gmYmaU ’$aH$ 'd' Amho Va ˶mMo ñdén.a, a + d, a + 2d, ........., a + (n – 1)d.
Amnë¶mbm ‘m{hV Amho ¶m nXm§Mm JwUmH$ma ì¶ñV H.P hmoVmo.
˶mMm Z‘wZm,
1 1 1 1, , ,..........2 ( 1)a a d a d a n d hm Amho.
H.P. Mm gm‘mݶ Z‘wZm
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Progressions 36
hm Amho
{Q>n : H.P.À¶m 'n' ì¶m nXm§Mr ~oarO H$mT>ʶmMo gyÌ Zmhr.
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1 : 1 1, ,1, 1,.......5 3 ¶m H.P Mo T10 H$mT>m.
CH$b :{Xboë¶m HP Mm JwUmH$ma ì¶ñV A.PAgVmo.5, 3, 1, –1......... ho A.P ‘ܶo AmhoV.a = 5, d = T2 – T1 = 3 – 5 = – 2, T10 = ?
Tn = a + (n – 1)dT10 = 5 + (10 – 1) (–2) = 5 + 9(–2) = 5 – 18 =-13.T10 = –13
A.P Mo 10 do nX T10 = –13 Amho.
g§JV H.P Mo T10 ho1
13 ho Amho.
CXmhaU 2 : H.P ‘ܶo T3 =1
7 Am{U T7 =1
5 . Va T15H$mT>m.
CH$b : AP Mo g§JV T3 Am{U T7 ho T3 = 7, T7 = 5 AmhoV.
d =T Tp q
p q = 7 3T T7 3
d =5 7
4 =
24
=12
d =1
2
g§JV AP Mo T3=7 g‘Oy.
a + 2d= 7 2a 12 = 7
a – 1 = 7a = 7 + 1a = 8 T15 H$mT>VmZm, Tn = a + (n – 1)d
T15= 8 + (15 – 1)1
2
T15= 8 147 1
2
gyÌ dmnê$Z gmoS>{dÊ`mMr n`m© r nÜXV
Tn =1
a+(n-1)d
= 1a + 2d 7
= a+2d
a+2d=7
VgoM a + 6 d = 5 (-) (-) _
_ 4d =2d =2/-4 =- 1/2
g‘rH$aU‹ (1) dê$Z a+2d=7
a + 2 (- 1 ) =7 2
a = 7 + 1=8
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Progressions 37
g ñdmܶm¶ 2.4
1. Imbrbn¡H$s H$moUVo JwUmH$ma ì¶ñV H«$‘mV AmhoV?
(i)1 1 11, , , ,......4 7 10 (ii)
2 1 21, , , ,......3 2 5 (iii)
1 1 1, , ,......2 6 18
(iv)1 1 1, , ,......3 7 11
(v) 6, 4, 3, ..... (vi)1 11, , ,......2 4
2. (i) Tn H$mT>m. (ii) 1 1, ,1,......7 4
H«$‘mMo T10 H$mT>m.
3. H.P ‘ܶo T5 =1
12Am{U T11 =
115
Va T25 H$mT>m.
4. H.P ‘ܶo T4 =111
Am{U T14 =3 ,23
Va (i) T7 (ii) T19 H$mT>m.
JwUmoÎma H«$‘ (Geometric progression)
Vwåhmbm H|${ж {dKQ>Z {H«$¶oMr ‘m{hVr Amho.
Ooìhm U - 235 da ݶyQ´>mMm ‘mao Ho$bm Va ˶m§Mo
{dKQ>Z hmodyZ 2 ݶyQ´>m°Z ‘wº$ hmoVmV. ho XmoZ
ݶyQ´>m°Z {dKQ>Z {H«$¶m nwT>o Mmby R>odVmV Am{U
nwT>rb nm¶arV 4 ݶyQ´>m°Z ‘wº$ hmoVmV Am{U ¶m
nw{T>b nm¶arV 8 ݶyQ´>m°Z Am{U hr {H«$¶m nwT>o
Mmby amhVo.
à˶oH$ nm¶arV ݶyQ>m°ZÀ¶m g§»¶oMo {ZarjU H$am.
nm¶ar I II III IV V VI .......
ݶyQ>m°ZMr g§»¶m 1 2 4 8 16 32 ........
1, 2, 4, 8, 16, ...... hm H«$‘ {‘iVmo.
¶oWo à˶oH$ nX ho ‘mJrb nXmÀ¶m XþßnQ> Amho åhUOoM.‘mJrb nXmbm 2 Zo JwUbo AgVm nwT>rb nX
{‘iVo..
AmUIr H$mhr CXmhaUo nmhm.
H «$‘ {Z¶‘3, 9, 27, 81, ..... 3 Zo JwUbo.1000, 100, 10, 1, ..... 1
10 Zo JwUbo.
5, 25, 125, 625, ..... 5 Zo JwUbo.
1 1 1, , ,......2 4 6
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Progressions 38
Aem àH$maÀ¶m H«$‘mbm JwUmoÎma H«$‘ åhUVmV. Vmo WmoS>³¶mV G.P. Ago {bhrVmV.‘mJrb nXmbm EH$m R>am{dH$ g§»¶oZo JwUbo AgVm nwT>rb g§»¶m ¶oUmè¶m H«$‘mbm JwUmoÎma
H«$‘ Ago åhUVmV.G.P, ‘ܶo nXm§Mo JwUmoÎma Am{U ˶m§Mo ‘mJrb nX ho eyݶ ahrV pñWa AgVo. ¶m pñWam§H$mbm gmYmaUJwUmoÎma åhUVmV. Am{U Vmo 'r' [c.r] Zo Xe©{dVmV.
H«$‘ 2
1
TT
3
2
TT
4
3
TT
3, 9, 27, 81,..... 3 3 3
1000, 100, 10, 1, ..... 110
110
110
5, 25, 125, 625, ..... 5 5 5
Oa T1, T2, T3, T4, ........ hr G.P, Mr nXo AmhoV Var = 2 3 4
1 2 3
T T T ..........T T T pñWa
H«$‘mMm g‘mdoe Agboë¶m {Z˶ OrdZmVrb H$m§hr KQ>Zm§Mr ¶mXr AmnU nmZ Z§.16 da Ho$bobr Amho.¶oWo,KQ>Zm 3 _Yrb àË oH$ Vmgmbm OrdmUyMr g§»`m XwßnQ> hmoVo Am{U åhUyZ Ë`mMm H«$_ ......... 50,
100, 200, 400, r =100 200 400 ......... 250 100 200
pñWaÁ¶mAWu Amåhmbm gm‘mB©H$ JwUmoÎma {‘iVo ˶mAWu Vmo H«$‘ G.P. Amho.KQ>Zm 4 ‘ܶo,{H$aUmoËgO©H$ Z‘wZm 100, 50, 25, 12.5, ......‘ܶo KQ>Vmo.
r =50 25 12.5 1......
100 50 25 2pñWa
Á¶mAWu gm‘mB©H$ (gmYmaU) JwUmoÎma pñWa Amho ˶mAWu Vmo H«$‘ G.P. Amho.G.P Mm gm‘mݶ Z‘wZm General form of a G.PJ§Jmbm g§Xoe Amnë¶m ‘¡{ÌUrbm nmR>dm¶Mm Amho. Á¶mAWu ˶m§Mm JQ> ‘moR>m Amho åhUyZ Vmo à˶oH$mn¶ªVnmohMy eH$V Zmhr. ˶m‘wio {VZo R>a{dbo H$s, hm g§Xoe {VKr n¶ªV nmohMdm¶Mm, ˶mZ§Va à˶oH$sZo{VKm§Zm nmR>dm`Mm Amho Am{U BË`mXr. ¶m KQ>ZoV V`ma hmoUma g§»¶mMm H«$_ H$moUVm Amho ?Imbrb AmH¥$Vr nmhÿZ g§»¶mMm H«$‘ Aä¶mg.................
T1 = 1 = 1 × 30 = 1 × 31 – 1 = aT2 = 3 = 1 × 3 = 1 × 31 = 1 × 32–1 = arT3 = 9 = 1 × 3 × 3 = 1 × 32 = 1 × 33 – 1 = ar2
T4 = 27 = 1 × 3 × 3 × 3 = 1 × 33 = 1 × 34 – 1 = ar3
Tn = 1 × 3 × 3 .....(n – 1) doim = 1 × 3n – 1 = a rn–1
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Progressions 39
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1: Oa a = 4 Am{U r = 2 AgVmZm G.P À¶m n{hbr 3 nXo H$mT>m.CH$b :T1 = a = 4T2 = ar = 4 × 2 = 8
T3 = ar2 = 4 × 22 = 16
G.P Mr n{hbr VrZ nXo 4, 8, 16. hr AmhoV.
CXmhaU 2 : 3 3 3, , ,.......2 4 8 ho G.P ‘ܶo AmhoV Va nmMdo nX H$mT>m.
CH$b. a = 32 , r = 2
1
3T 343T
2 4 2
23
12 , T5 = ?
Tn = arn – 1
T5 =5 13 1
2 2 =
43 12 2
=3 12 16
= T5 =332
CXmhaU 3: 2,2 2,4,...... ¶m G. P Mo H$moUVo nX 32 Amho?
CH$b : a = 2, r = 2
1
T 2T
22
2 , Tn = 32, n = ?
Tn = arn – 1
32 = 12 2
n
3216
2= 1
2n 16 = 1
2n
24 = 12
n = (2½)n – 1 ½2 2
24 =1
22n
4 =1
2n
G.P, ‘ܶo Oa n{hbo nX 'a' gmYmaU JwUmoÎma 'r' Amho. Va G.P Mm Z‘wZm,a, ar, ar2, ar3 ............ar n – 1
G.P : Mo gmYmaU nX Tn = ar n – 1
{Q>n : gmYmaU JwUmoÎma 'r' Agboë¶m G.P ‘ܶo.
* nT>rb nX {‘i{dʶmgmR>r 'r' Zo JwUUo Tn + 1 = Tn × r
* ‘mJrb nX {‘i{dʶmgmR>r 'r' Zo mJUo. Tn–1 = Tn r
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Progressions 40
8 = n – 1 n = 8 + 1 = 9
G.P.Mo 9 do nX 32 Amho.CXmhaU 4:Mo G.P. n{hbo nX 25 Am{U 6do nX 800 Amho Va gmVdo nX H$mT>m?
CH$b : a = 25, T6 = 800, T7 = ?
T7, H$mT>V AgVmZm àW‘ Amnë¶mbm n{hbo nX r H$mT>mdo bmJob.
T6 = 800 ar5 = 800 Amåhmbm ‘mhrV Amho H$s, Tn + 1 = Tn × r
25 × r5 = 800 T7 = T6 × r
r5 =80025 = 32 T7 = 800 × 2
r5 = 25
r = 2 T7 = 1600
ñdmܶm¶ 2 .5
1. Imbrb G.P ‘Yrb gmYmaU JwUmoÎma H$mT>m.(i) –5, 1,
1,5
......... (ii) 3,3,3 3,........ .
2. gyMZoà‘mUo H$am.
(i) Oa a = 1 Am{U r = 23 Va (a) Tn (b) T4 H$mT>m. (ii) 729, 243, 81,...... ¶m G.P Mo T7
H$mT>m.
3. 5do nX 64 Am{U gmYmaU JwUmoÎma 2 AgUmè¶m G.P Mo 12 do nX H$mT>m.
4. Imbrbm§Mr qH$‘V H$mT>m.
i) 256, 128, 64, .....¶m G.P.Mo 10 do 16 do nX H$mT>m .
ii) 81, -27, 9, ¶m G.P. Mo 8 do Am{U 12 do nX.
iii) 0.008, 0.04, 0.2 ..... ¶m G.P. Mo 4Wo Am{U 8do nX.
5. Imbrb loUtMo eodQ>Mo nX H$mT>m.
i) 2, 4, 8 ..... 9ì¶m nXmn¶ªV. ii)4, 42, 43 ..... 2n ì¶m nXmn¶ªV
iii) 2, 3, 412
..... 6ì¶m nXmn¶ªV iv) x , 1, 20 ì¶m nXmn¶ªV
6. Oa T5 : T10 = 32 : 1 Am{U T7 = 132Va G.P H$mT>m.
1 . . . .x
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Progressions 41
7. H$m§hr {H$aUmoËgO©H$ nXmWmªMm AY© OrdZ H$mi 1 Vmg Amho. Oa nXmWm©À¶m gwadmVrÀ¶m Z‘wݶmModñVw‘mZ 500 J«°‘ Amho. Va 5ì¶m VmgmZ§Va {e„H$ Agbobo Z‘wݶmMo dñVw‘mZ {H$Vr?
8. 3, 6, 12, ..... ¶m H«$‘mMo H$moUVo nX 1536 hmoB©b?
9. EH$m Mo 4Wo Am{U 8do nX AZwH«$‘o 24 Am{U 384 Amho Va n{hbo nX Am{U gmYmaU JwUmoÎmaH$mT>m.
10. Imbrb G.P. H$mT>m.
i) 10do nX 320 Am{U 6do nX 20 Amho.
ii) 2ao nX 6 Am{U 6 do nX 9 6 Amho.
JwUmoÎma loUr (Geometric Series.)
loUrMr nXo JwUmoÎma H«$‘mV AgVrb Va {Vbm JwUmoÎma loUr Ago åhUVmV.
CXm : 1 + 3 + 9 + 27 = 401 1 152 12 4 4
G.P À¶m n{hë¶m n nXm§Mr ~oarO (Sum of the first n terms of a G.P)
10 {‘Ì EH${ÌVnUo JmoQ>çm§Mm Ioi IoiV AmhoV. n{hë¶m 춺$sH$S>o 2 JmoQ>çm AmhoV. Xþgè¶m 춺$sH$S>on{hë¶m 춺$sH$S>o Agboë¶m JmoQ>çm§À¶m XþßnQ> AmhoV. {Vgè¶m 춺$sH$S>o Xþgè¶m Odi Agboë¶mÀ¶mXþßnQ> AmhoV Am{U B˶mXr.
˶m§À¶m Odi Agboë¶m EHy$U JmoQ>çm Mr g»¶m {H$Vr?
hr loUr Aer {bhrbr OmVo H$s,
2 + 4 + 8 + ......... + T10
21 + 22 + 23 + ............. + 210
n«Ë¶oH$mMr qH$‘V H$mTy>Z ~oarO H$aʶmMr nÜXV doi H$mTy> Am{U H§$Q>midmUr Amho.
Vr gmo߶m àH$mao Imbrb à‘mUo Ho$br OmD$ eH$Vo
a + ar + ar2 + ........ + arn – 1 hr n{hbo nX 'a' Am{U gmYmaU JwUmoÎma 'r' Agboë¶m 'n' nXm§Mr~oarO Amho Ago ‘m§Zy.
Sn= a + ar + ar2 + .................. + arn – 1
'r' Zo JwUbo.
r Sn= ar + ar2 + ar3 + ............ + arn
Sn a ar 2ar 1.......... narSnr ar 2ar 1........... nar
( ) ( ) ( ) ( ) ( ) ( )
S .S
n
nn n
ar
r a ar hm g§~§Y nwÝhm Agm {bhrbm OmVmo.
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Progressions 42
Sn – r. Sn = a – arn
Sn (1 – r) = a (1– rn)
Oa r=1Amåhr XmoÝhr ~mOwZm 1 – r Zo
^mJ {Xë¶mg Amåhmbm {‘iVo
n
na(1 - r )S =
1 - r Ooìhm < 1n
na r -1S =
r -1 Ooìhm r > 1
Oa r < 1, 1-r < 0 AmUr darb à‘mUo Amåhr gyÌ dmnaVmo.{Q>n: Oa r =1 Va Sn = a + a + a....n doim = na.
hm g§~§Y H$mT>ë¶mZ§Va, nmZ Z§. 14 (¶m KQ>H$mVrb) Vwåhr dmMbobo Amho, amOmbm emoYH$mMr‘mJUr nwa{dUo H${R>U Jobo ¶mMo H$maU Vwåhmbm emoYUo e³¶ hmoB©b.
~wÜXr~i Ioim‘ܶo 64 Mm¡ag AmhoV.
JhÿÀ¶m YmݶmMr Mm¡agm‘ܶo R>odʶmMr g§»¶m G.P. ~Z{dVo.1, 2, 4, 8, ..............263
a = 1, r =2
1
T 2=T 1 = 2, n = 64
OmUyZ ¿¶m
Sn =( 1)
1
na rr
S64= 18, 446, 744, 073, 709, 551, 615
S64 =64 641 2 1 1 2 1
2 1 1S64 = 264 – 1
ho YmÝ` _moOÊ`mg {H$Vr doi bmJob ? emoYH$mMr ‘mJUr ¶mo½¶ hmoVr H$m?A‘¶m©{XV JwUmoÎma loUrÀ¶m nXm§Mr ~oarO H$mT>Uo [ Ooìhm r < 1]‘¶m©{XV JwUmoÎma loUrMr ~oarO H$mT>ʶmMm Vwåhr Aä¶mg Ho$bobm Amho.Imbrb CXmhaUmMm {dMma H$am.
1 1 11 ......2 4 8 S ¶m G.P Mm {dMma H$é.
¶oWo, a = 1. r =1 121 2
g§~§YmnmgyZ gwadmV H$é Ago ‘m§Zy.
Sn =[1 ]1
na rr
Oa r > 1 V§oìhm 1-r < 0 Am{U A§e Am{U N>oX¶mZm -1 Zo JwUmH$ma H$ê$Z darb g§~§Y nwÝhmImbrb à‘mUo {bhrVm ¶oVmo.
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Progressions 43
Sn =11 1 211 2
n
=11 1 2
12
n
=11 2
12
n
¶oWo 'n' Mr qH$‘V dmT>Vo Voìhm 12
nMo H$m¶ KS>Vo Vo nmhÿ.
n = 1,11
2 = 12 = 0.5
n = 2,21
2 = 14 = 0.25
n = 331
2 = 18 = 0.125
n = 4,41
2 = 116 = 0.0625
n = 8,81
2 = 1256 = 0.00391
n = 10,101
2 = 11024 = 0.00098
'n' ho Odi Amho, Va 'arn' Mr qH$‘V eyݶmOdi ¶oVo. (ho H$Yrhr eyݶ ZgVo) åhUyZ qH$‘V
(A˶§V H$‘r) AgVo.darb CXmhaUmgmR>r S hrS =
11 212
=
12 Xþb©{jV Ho$bobo Amho
S = 2
n¶m©¶r nÜXV :
A E1 unit 1 unit B
1u
nit
1un
it
F
D C
G ½ unit H
I K1/4 unit
L N1/8
O Q
J
M
P
R S
1/16
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Progressions 44
ABCD hm 2 EH$H$ ~mOyMm Mm¡ag Amho. A‘¶m©{XVo n¶ªV aoIm§{H$V mJmÀ¶m joÌ’$im§Mr ~oarOH$mT>ʶmMm à¶ËZ H$é¶m.
{Z[ajU H$am H$s, aoIm§H$sV ^mJ Mm¡ag AmhoV.
ñ‘aU H$am H$s, Mm¡agmMo joÌ’$i = a2
[AEGF + GHIJ + IKLM + .........] Mo joÌ’$i
=2 2 2
2 1 1 11 .........2 4 8
n¶ªV
=1 1 11 ........4 16 64 n¶ªV
n{hë¶m, "n" Mm¡agm§À¶m joÌ’$im§Mr ~oarO H$mTy>.
¶oWo, a = 1, r =1
4 11 4
n{hë¶m, "n" Mm¡agm§À¶m joÌ’$im§Mr ~oarO = a + ar + ar2 + ........ + arn – 1
Sn =[1 ]1
na rr
=11 1 411 4
n
=11 4
43
n
{ZarjU H$am H$s "n" OgOgo ‘moR>‘moR>o hmoVo Vg Vgo 14
n bhmZ bhmZ ~ZV OmVo.
14 H$amho BVHo$ bmhmZ hmho H$s Vo Odi Odi eyݶ hmoVo.
åhUyZ aoIm§H$sV mJmMo joÌ’$i,1-0 1
4 4
43 3 3
S
VgoM OoÁhm r < 1 Am{U "n" A˶§V ‘moR>o AgVo Voìhm r A˶§V bhmZ hmoVo.( Odi Odi eyݶ)
1-0
1-S
a
r =
a=1 - r
S
MMm© H$am : r > 1. Va A‘¶m©{XV JwUmoÎma loUtMr ~oarO H$mT>Uo Ae³¶ Amho. JQ>mZo MMm© H$am.
¶oWo, H$m§hr G.P r < 1 À¶m A‘¶m©{XoVoÀ¶m ~oaOoMo ‘‚moera Cn¶moJ AmhoV.
CXmhaU : 0.6666...... hr g§»¶m n[a‘o¶ g§»¶oÀ¶m ñdénmV 춺$ H$am.
CH$b : ho AmnU 0.6 + 0.06 + 0.006 + 0.0006 + .......Agohr {bhÿ eH$Vmo.
11 212
n
3 4
4=
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Progressions 45
a = 0.6, r =0.060.6
= 0.1
S =a
1 r-S =
0.61 0.1
=0.60.9
S = 23
23 hr n[a‘o¶ g§»¶m Amho Ooìhm hr 0.6 ¶m Xem§em‘ܶo Xe©{dbobr AgVo.
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1 : 3, 6, 12, ....... ¶m G.P À¶m n{hë¶m 6 nXm§Mr ~oarO H$mT>m.
CH$b :¶oWo a = 3, r =2
1
T 6 2T 3 , n = 6
Sn =( 1)
1
na rr
[ r > 1]
S6 =63[2 1]
2 1=
3[64 1]1
= 3 × 63
S6 = 189
CXmhaU 2 : 1 + 4 + 16 + ..... ¶m loUrÀ¶m {H$Vr nXm§Mr ~oarO 1365 hmoB©b?
CH$b : ¶oWo, a = 1, r = 41 = 4, Sn = 1,365, n = ?
Sn =( 1)
1
na rr
[ r > 1]
1365 =1 4 1
4 1
n
=1
3
n
1365 × 3 = 4n – 14 095 = 4n – 1
40 95 + 1 = 4n
40 96 = 4n
46 = 4n
n = 6
CXmhaU 3 : 2 22 + + + ..........3 9 ¶m G.P À¶m nXm§Mr ~oarO n¶ªV H$mT>m..
CH$b : ¶oWo, a = 2, r =2 232
13 2
13
, S = ?
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Progressions 46
S = 1a
r
S = 2113
=2
23
S = 2 32
S = 3
CXmhaU4 : Oa G.P Mo {Vgao nX 12 Am{U ˶mMo 6do nX 96 Amho Va 9 nXm§Mr ~oarO H$mT>m.CH$b : T3 = 12 Am{U T6 = 96
T3 = 12ar2 = 12 ......(1) ar5 = 96 ......(2)
(2) bm (1) Zo ^mJ Úm.5
2
arar
=9612
r3 = 8r3 = 23
r 2=
g‘Om, ar2= 12a(2)2 = 12a × 4 = 12 a =
3a
AmVm AmnU S9.H$mTy>.
Sn =( 1)
1
na rr
S9 =93(2 1)
2 1=
3(512 1)1 = 3(511)
9 1533S
CXmhaU 5: G.P À¶m VrZ nXm§Mr ~oarO 31 Am{U ˶m§Mm JwUmH$ma 125 Amho. Va ˶mg§»¶m H$mT>m.
CH$b : be ,ar
a, ar hr G.P Mr VrZ nXo AmhoV Ago ‘m§Zy.
VrZ nXm§Mm JwUmH$ma = 125
{Q>n :
Oap>q
TT
p
q = rp-q
{Q>n S n =rn+1
Sn
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Progressions 47
ar
a a r = 125
a3 = 125
a = 3 125 a = 5
VrZ nXm§Mr ~oarO = 31
a a arr = 31
5 5 5rr = 31
5 5rr = 31 – 5 Þ
25 5rr
= 26
5 + 5r2 = 26r5r2 – 26r + 5 = 0
5r2 – 25r – r + 5 = 05r(r – 5) – 1(r – 5 = 0
(r – 5)(5r – 1) = 0
5r – 1 = 0 qH$dm r – 5 = 0
r = 15 qH$dm r = 5
Oa a = 5 Am{U r = 15 , Va ˶mMr nXo
ar
=5 5
51 15 = 25
a = 5
ar =155
= 1
Oa a = 5 Am{U r = 5 Va ˶m§Mr nXo.ar =
51
5= a = 5 ar = 5 × 5 = 25
3 nXo 25, 5, 1 qH$dm 1,5,25, hr AmhoV. ñdmܶm¶ 2.6
1. Imbrb JwUmoÎma loUtMr ~oarO H$mT>m.(i) 1 + 2 + 4 + .... 10ì¶m nXmn¶ªV
(ii)1 1
1 ........3 9
+ + + n¶ªV
1 24
3
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Progressions 48
2. r = 2 Am{U S8 = 510 AgVmZm G.P Mo n{hbo nX H$mT>m.3. G.P Mr ~oarO H$mT>m (i)1 + 2 + 4 + ...... + 512 (ii) 10
1 1 1.........2 4 2
4. 2 + 4 + 8 + ...... ¶m loUrÀ¶m {H$Vr nXm§Mr ~oarO 1022 hmoB©b?
5. emoYm, (i) 5 + 10 + 20 + .......¶m loUrMr S2 : S4
(ii) 4 + 12 + 36 + .....¶m loUrMr S4 : S8
6. G.P H$mT>m Oa, (i) S6 : S3 = 126 : 1Am{U T4 = 125 (ii) S10 : S5 = 33 : 32 Am{U T5 = 64
7. A‘¶m©{XV JwUmoÎma loUrMo n{hbo nX 6 Am{U ~oarO 8 Amho Va G.P. H$mT>m.
8. G.PMr VrZ nXo H$mT>m, Oa ˶m§Mr ~oarO Am{U JwUmH$ma AZwH«$‘o (i) 7 Am{U 8
(ii) 21 Am{U 216 (iii) 19 Am{U216 AmhoV.
9. EH$m ì`ŠVr Zo _mJrb dfm©À`m ~MVrÀ`m AYu aŠH$_ àË`oH$ dfu ~MV Ho$br Oa nmM dfm©_Ü`oË`mZo Ho$bobr ~MV 19,375 Amho Va Ë`mZo n{hë`m dfu Ho$bobr ~MV {H$Vr?
A§H$J{UVr ‘ܶ (Arithmetic Mean (A.M.))Imbr {Xbobo H$moï>H$ nmhm.
A.P ‘ܶ {ZarjU H$am1, 6, 11
1 6 11 186
3 3+ +
= =1 11 12
62 2
+= =
2, 8, 142 8 14 24
83 3
+ += =
2 14 168
2 2+
= =
7, 12, 177 12 17 36
123 3
+ += =
7 17 2412
2 2+
= =
AmnU nm{hbo H$s, Oa VrZ nXo AP ‘ܶo AmhoV Va ‘Ybo nX ho BVa XmoZ nXm§Mr gamgar Amho.A{U ˶mbm BVa XmoZ g§»¶mMm A§H$J{UVr ‘ܶ åhUVmV.
a,A, b ho A.P ‘ܶo AmhoV Va A = 2a b+
a, A, b ho A.P ‘ܶo AmhoVVa,A – a = b – A [ d = T2 – T1 = T3 – T2]A + A = a + b
2A = a + b
XmoZ g§»¶m§Mm A§H$J{UVr ‘ܶ hm XmoZ g§»¶m§À¶m ~oaOoÀ¶m {Zå‘m AgVmo.
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Progressions 49
ñnï>rH$aUmË‘H$ CXmhaUoCXmhaU 1 : 7 Am{U 13 Mm A§H$J{UVr ‘ܶ H$mT>m.CH$b : a = 7, b = 13
A.M =7 13
2 2a b+ +
= =202 = 10
AM = 10
CXmhaU 2 : Oa (p – q), x, (p + q) ho A.P.‘ܶo AmhoV Va 'x' H$mT>m.CH$b : a = p – q, AM = x, b = p + q
A.M = 2a b+
x =p q- p q+ +
2=
22p
x = p
JwUmH$ma ì¶ñV ‘ܶ (H.M) (Harmonic Mean)
Oa VrZ nXo H.P ‘ܶo AmhoV, Va ‘Yë¶m nXmbm BVa XmoZ nXm§Mm JwUmH$ma ì¶ñV ‘ܶ åhUVmV.Oa a,H,b ho H.P ‘ܶo AmhoV.
Va 1 1 1, ,
a H b ho A.P.‘ܶo AmhoV.
1 1H a =
1 1Hb [ d = T2 – T1 = T3 – T2]
1 1H H =
1 1a b
+
2H =
b aab+
2ab = H(a + b)
XmoZ g§»¶m§Mm JwUmH$ma ì¶ñV ‘ܶ hm ˶m§À¶m JwUmH$mamÀ¶m XþßnQ>rbm ~oaOoZo mJ {Xbm AgVm ˶m§À¶merg‘mZ AgVmo.
ñnï>rH$aUmË‘H$ CXmhaUoCXmhaU 1 : 1 Am{U 9 ‘Yrb JwUmH$ma ì¶ñV ‘ܶ H$mT>m.CH$b : a = 1 Am{U b = 9
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Progressions 50
4M =2ab
a b+ =2 1 9 18
1 9 10HM = 1.8
JwUmoÎma ‘ܶ (G.M)
Oa H$moUVrhr VrZ nXo G.P ‘ܶo AmhoV, Va ‘Yrb nXmbm BVa XmoZ nXm§Mo JwUmoÎma ‘ܶ åhUVmV.CXm : G.P Mean Observe
1, 3, 9 3 1 9 9 3= =4, 8, 16 8 4 16 64 8= =1000, 100, 10 100 1000 10 10000 100´ = =
Oa a, G, b ho G.P,‘ܶo AmhoV Va G = a b
Oa a, G, b ho G.P,‘ܶo AmhoV.
GGb
a= 2 3
1 2
T TT T
G2 = a × b
G a b
H$moU˶mhr XmoZ g§»¶mMm JwUmoÎma ‘ܶ hm ˶m§À¶m JwUmH$mamMo dJ©‘yi AgVo.
ñnï>rH$aUmËm‘H$ CXmhaUoCXmhaU 1:4 Am{U 36 ‘Yrb G.M H$mT>m.CH$b :a = 4, b = 36G = a b = 4 36 144=
G = 12 $
A.M, G.M Am{U H.M ‘Yrb g§~§Y(I) Oa 'a' Am{U 'b' ¶m XmoZ YZ g§»¶m§Mm A, G, H ho AM, GM Am{U HM AmhoV Va A, G H ho
G.P. ‘ܶo AmhoV. 'a' Am{U 'b' ¶m XmoZ YZ g§»¶m§gmR>r Amnë¶mbm ‘m{hV Amho H$s,
CXmhaU 2 : Oa 6, x + 2, 54 hr G.P
‘ܶo AmhoV Va x H$mT>m.CH$b : a = 6, G = x + 2, b = 54
G = a b x + 2 = =6 54 324x + 2 = 18
x = 18 – 2 = 16x = 16
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Progressions 51
A. M A = 2a b+
G.M G = ab H.M H =2ab
a b+
g‘Om, , A × H =a b+
22
´ab
a b+ = ab
A H= ab
A H = G.
G hm A Am{U H Mm JwUmoÎma ‘ܶ Amho.A, G, H ho G.P ‘ܶo AmhoV.
CXmhaU 1 : .Oa, a = 2 Am{U b = 32, Va A.M., G.M. Am{U H.M. H$mT>m.
CH$b : A.M =2 32 34
172 2 2
a b+ += = =
G.M = 2 32 64 8ab = = =
H. M =2 2 2 32 128 64
2 32 34 17ab
a b= = =
+ +Vmim : G = A H
G = 176417 = 64
G = 8
CXmhaU 2 : a Am{U b À¶m {Xboë¶m qH$‘Vrbm AM, GM Am{U HM H$mT>m.CH$b : (i) Oa a = 4, b = 16
AM =4 16 20
102 2 2
a b+ += = =
GM = 4 16 64 8ab = = =
HM =2 2 4 16 128
6.44 16 20
aba b
= = =+ +
(ii) a = 3, b = 27
AM =3 27 30
152 2 2
a b+ += = =
GM = 3 27 81 9ab = = =
HM =2 2 3 27 2 3 27
5.43 27 30
aba b
= = =+ +
(iii) a = 2, b = 50
AM =2 50 52
262 2 2
a b+ += = =
GM = 2 50 100 10ab = = =
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Progressions 52
HM =2 2 2 50 2 2 50
3.82 50 52
aba b
= = =+ +
darb H$moï>H$mdéZ AmnU Agm {ZîH$f© H$mTy> eH$Vmo H$s, a Am{U b, ¶m H$moU˶mhr XmoZ YZg§»¶mgmR>r.
a b A G H4 16 10 8 6.43 27 15 9 5.42 50 26 10 3.8
A > G > H ..... (1)
nmhm,(i) Oa a = 3, b = 3 Va
AM =3 3 6
32 2 2
a b+ += = =
GM = == 3 3 3a b
HM =2 2 3 3 2 3
3 3a b
a b= =
+ +3
63=
(ii) Oa a = 17, b = 17 Va
AM =17 17 34 17
2 2 2a b
GM = 17 17 17a b
HM =2 2 17 17 2 17
17 17ab
a b17
3417
darb CXmhaUm dê$Z Amåhr Agm {ZîH$f© H$mTy> H$s, Oa a = b VaA.M = G.M = H.M .......(2)1 Am{U 2, À¶m {ZH$bmdéZ, Amnë¶mbm ‘m{hV Amho H$s, 'a' A{U'b', ¶m H$moU˶mhr XmoZ YZ
g§»¶mgmR>r A.M G.M H.M
ñdmܶm¶ 2.7
1. Imbrb g§»¶m§‘Yrb A.M. GM d H.M H$mT>m.
(i) 12 Am{U 30 (ii) 12 Am{U 1
8 (iii)-8 Am{U -42 ( iv) 9 Am{U 18
2. Oa 5, 8, x ho H.P ‘ܶo AmhoV Va x H$mT>m.
3. Imbrb nXo A.P AmhoV Va x H$mT>m.
> >
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Progressions 53
(i) 5, (x – 1), 0 (ii) (a + b)2, x, (a – b)2
4. XmoZ g§»¶m§Mm JwUmH$ma 119 Am{U ˶m§Mm A§H$J{UVr ‘ܶ 12 Amho Va ˶m g§»¶m H$mT>m.
5 Oa 2, x,12 ho G.P ‘ܶo AmhoV Va x H$mT>m.
6. XmoZ g§»¶m§Mm A§H$J{UVr ‘ܶ 17 Am{U ˶m§Mm JwUmoÎma ‘ܶ 15 Amho Va ˶m g§»¶m H$mT>m.
7. XmoZ g§»¶m§Mm A§H$J{UVr ‘ܶ 132 Am{U ˶m§Mm JwUmoÎma ‘ܶ 6 Amho. Va ˶m§Mm JwUmoÎma ì¶ñV ‘ܶ
H$mT>m..
H«$_H«$_
Arithmeticprogression
Progressions
T = a+(n–1)dn
Arithmeticseries
Harmonicprogression
Geometricprogression
11nT
a (n )d
Geometricseries
T = a.rn n–1
nnS = [2a+(n-1)d]2
When r>11
1
n
na(r )
Sr
Finite geometricseries
Infinite GeometricSeries
When r<111
n
na( r )
Sr
11
aS ,whenr
r
AM, GM & HM
AM=a+b2
GM = ba
AM GM HM
HM=2ab+a b
G A H
First n naturalnumbers
12n
n(n )S =
Ooìhm
H«$_
A§H$J{UVr H«$‘ JwUmoÎma H«$‘
A§H$J{UVr loUr JwUmoÎma loUr
‘¶m©{XV JwUmoÎma loUrZ¡g{J©H$ g§»¶m§Mr ~oarOA‘¶m©{XV JwUmoÎmaloUr S
Ooìhm
JwUmH$ma ì`ñV
H«$‘
Ooìhm
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Progressions 54
ñdmܶm¶ 2.1
1. (i), (ii), (iv) ho H«$‘ AmhoV 2. ( ii )19,21 (ii) 6 75 6, (iii) 0.001, 0.0001 (iv) 48,96 3)
.1,3, -7 4) (i) T3 = 23 T10 = 205, 5) (i) n2 - 2n (ii) n2+2n(6) n=14ñdmܶm¶ 2.2
1. (i)-12, 15, -18, - 21. (ii) 2, 5, 1, 7 (iii) a-5b, a-7b, a-9b, a-11b.3 6 6
2) (i) 1,3,5 .........(ii) 6, 11,16 .....3) (i) 48 (ii) - 148 (iii) 17 (iv) 3 (v) 3.4) 23 5) 600 Am{U 700 6) 64
7) - 13, - 8, -3. 8) 10:3 9) df© 2012 10) 5.9,13, 17. qH$dm 17,13,9,5ñdmܶm¶ : 2.3
1. 21 2. (i) 1275 (ii) 493 (iii) 4a2-a3 (vi) P2/2(3-P)
3. 15 4. (a) (i) 210 (ii)455 (iii) 585 (b) (i) 10 (ii) 5 5. n2 6. 4100
7. 3, 10, 17, 24. 8) 6
9. (i) 3, 7, 11 qH$dm 11,7,3 (ii) 9, 12, 15. qH$dm 15,12,9 10. 30, 41, 52, 63, 74, 85.
11. -1100 12. 551
ñdmܶm¶ 2.41. (i), (ii), (iv), (v) 2(i) 1 (ii) -1 3. 1 4. (i) 1 (ii) 1
2n 20 22 10 6
. ñdmܶm¶ 2.51. (i) -1
5(ii) 3 2. (i) (a) (2/3) n-1 (b) 8/27 (ii) 1. 3. 8192
4.(i) T10 = 1/2. T16 = 1/128 (ii) T8 = -1/27, T12 = - 1/2187
(iii) T4 = 1, T8 = 625.
5. (i) 512 (ii) 42n (iii) 243/16 (iv) 1/x28,
6. 2, 1, 1/2, ...... 7. 15.625 J«°‘.
8. 10 do nX 9. r = 2, a = 3 10. (i) 5/8, 5/4, 5/2 .... (ii) 2, 6, 3 2
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Progressions 55
ñdmܶm¶ 2.61. (i) 1023 (ii) 3/2 .2 3. (i) 1023 (ii) 1023/1024
4. 9, 5 (i) 1:5 (ii) 1: 82 6. (i) 1, 5, 25,..... (ii) 1024, 512, 256......
7. 6, 3/2, 3/8, ..... 8. (i) 1, 2, 4. qH$dm 4,2,1 (ii) 3, 6, 12 qH$dm 12,6,3 (iii) 4, 6, 9. qH$dm
9, 6,4 9. < 10,000
ñdmܶm¶ 2.7
1. (i) AM = 21, GM= 6 10 , HM =120
7(ii) AM =
516
, GM =14
, HM =15
(iii) AM = 25, GM = 4 21 , HM =33625 (iv) AM =
272 , GM = 9 2 , HM = 12
2.20 3. (i)72 (ii) a2 + b2 4. 7 Am{U 17 5. 1
6. 9 Am{U 25 7.7213
********
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56
¶m KQ>H$m‘wio Vwåhmbm Imbrb JmoîQ>rMo gwb^rH$aU hmoVo.
* ¶wp³bS>À¶m boå‘mMo ñnï>rH$aU H$aʶmg
* ¶wp³bS>Mm ^mJmH$ma AëJmoarW‘ ( H$m¶m©dbr) dmnéZ
‘.gm.{d. H$mT>ʶmgmR>r,
* A§H$J{UVm ‘Yrb ‘wb yV à‘o¶ 춺$ H$aʶmgmR>r.
* Cnà‘o¶ {gÜX H$aʶmg,
* 2, 3, 5 ¶m An[a‘o¶ g§»¶m AmhoV ho
{gÜX H$aʶmg,
.
* ¶wp³bS>Mm boå‘m
* A§H$J{UVm ‘Yrb ‘yb yV à‘o¶
* Cnà‘o¶
* g§»¶m§Mm ‘.gm.{d
3
Mathematics is the queen of sciences,and Arithmetic is the queen of Mathematics.
-C.F. Gauss
Abo³Pm§S>r¶mMo ¶y³brS>, 300 B.g. nyd©. ˶ m §Z r Abo³Pm §S ´ > r¶m‘Yrb
{díd{dÚmb¶m‘ܶo J{UVmMr emim H$mT>br.A‘¶m©{XV AZoH$ ‘yi g§»¶m AmhoV ho {gÜXH$aUmao Vo n{hbo AmhoV.‘.gm.{d. H$mT>ʶmgmR>r¶wp³bS>À¶m AëJmoarW‘Mr ¶moOZm ˶m§Zr Ho$br.˶m§Zr ’$º$ 5 ßboQ>m°{ZH$ KZ (Platonic Sol-ids) Agë¶mMo {gÜX Ho$bo. ""X E{b‘|Q>'' ¶m13 ^mJ Agboë¶m J«§Wm§À¶m ì¶mnH$ (Com-prehensive) J{UVr nwñVH$mMo boIH$ AmhoV.AZoH$doim ˶m§Zm " w{‘VrMo OZH$' åhUyZ g§~mo{YboOmVo.
dmñVd g§»¶m(Real Numbers)
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Real Numbers 57
Vwåhmbm doJdoJù¶m àH$maÀ¶m g§»¶m Am{U ˶m‘Yrb g§~§Y ¶m{df¶r ‘m{hVr Amho. Imbrb AmH¥$VrMo {ZarjU H$am.R
QZ
WN
Q
¶m g§»¶mdarb ‘yb^yV {H«$¶m Am{U ˶m§Mo ‘hËdnyU© JwUY‘m©{df¶rMm Aä¶mg Vwåhr Ho$bobm Amho.J{UVm‘Yrb Am{U BVa {df¶m‘Yrb AZoH$ g‘ñ¶m gmoS>{dʶmgmR>r ¶m JwUY‘mªMr ‘XV hmoVo.
AmVm AmnU dmñVd g§»¶m, ˶m§Mo JwUY‘© Am{U Cn¶moJ ¶m{df¶r A{YH$ Aä¶mg H$é¶m.àW‘, AmnU g§»¶mdarb à{gÜX H$moS>çmMm {dMma H$é,EH$m PmonS>r‘ܶo 120 nojm OmñV ‘|T>ao(Sheep) Agy eH$V ZmhrV.Oa XmoZÀ¶m nQ>rV ‘moObr Va EH$ {e„H$ amhVo.Oa VrZÀ¶m nQ>rV ‘moObr Va XmoZ {e„H$ amhVmV.Oa MmaÀ¶m nQ>rV ‘moObr Va VrZ {e„H$ amhVmV.Oa nmMÀ¶m nQ>rV ‘moObr Va Mma {e„H$ amhVmV.Oa ghmÀ¶m nQ>rV ‘moObr Va nmM {e„H$ amhVmV.Oa gmVÀ¶m nQ>rV ‘moObr Va H$m§hr {e„H$ amhmV ZmhrV.Va PmonS>r‘ܶo Agboë¶m ‘|T>am§Mr g§»¶m {H$Vr ?nS>Vmim H$aʶmgmR>r g§»¶m§Mm H$moUVm JwUY‘© dmnabm nm{hOo?àW‘ JwUY‘mªMm Aä¶mg H$é¶m Am{U Z§Va H$moS>o gmoS>dy¶m..
nyUmªH$mMr {d^mÁ¶Vm (Divisibility of Integers)Amåhmbm ^mJmH$mamÀ¶m ‘yb yV {H«$¶m§Mr ‘m{hVr Amho.
Amåhr åhUVmo H$s b bm a Zo ^mJ OmVmo Oa H$moU˶mhr k ¶m Z¡g{J©H$ g§»¶ogmR>r b=KaOoìhm ^mÁ¶mbm ^mOH$mZo ^mJ {Xbm OmVmo, Voìhm Amåhmbm g§JV ^mJmH$ma Am{U ~mH$s {‘iVo ¶m Mma
nXm‘Yrb g§~§Y ^mÁ¶ =(^mOH$ × ^mJmH$ma) + ~mH$s‘a‘ hm ^mÁ¶, ‘b‘ hm ^mOH$,
‘q‘ hm ^mJmH$ma Am{U ‘r‘ hr ~mH$s Amho. Ago g‘Oy.¶m nXm‘Yrb g§~§Y a= (b x q) + r Zo Xe©{dVmV
‘m{hV Agboë¶m ¶m g§~§Ymbm ^y{‘VrÀ¶m OZH$mMo Zm§d XoʶmV Ambo Amho, ¶mbm "¶wp³bS>Mm ^mJmH$maboå‘m" ( EUCLID'S DIVISION LEMMA) Ago åhUVmV.
boå‘m: hm EH$ gmYm {ZH$mb Amho, Á¶mMm ‘w»¶ CÔoe à‘o¶ {gÜX H$aʶmg ‘XV H$aUo hm Amho. boå‘m ho à‘o¶{gÜX H$aʶmÀ`m ‘mJm©Vrb AmYma yV gmYZ Amho. åhUyZ ho {gÜX Ho$bobo {dYmZ Amho Á¶mMm Cn¶moJ BVa{dYmZo {gÜX H$aVmZm hmoVmo.
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Real Numbers 58
'a' Am{U 'b' ¶m YZ nyUmªH$mgmR>r'q' Am{U 'r' ho doJio (A{ÛVr¶) nyUmªH$ Aem [aVrZo AmT>iVmVH$s, a = bq + r, 0 r < b
hm ‘m{hV Agbobm {ZH$mb Amho, Omo ¶wp³bS>À¶m E{b‘|Q> nwñVH$mÀ¶m VII ^mJmV g§J«hrV Amho¶m boå‘m Mo {H$˶oH$ Cn¶moJ AmhoV, XmoZ YZ nyUmªH$mMm ‘.gm.{d. gwb^nUo H$mT>bm OmVmo ¶m nÜXVrbm
¶wp³bS>Mm ^mJmH$ma AëJmo[aW‘ åhUVmV.ñ‘aU H$am H$s, ‘a’ Am{U ‘b’ ¶m XmoZ YZ nyUmªH$mMm ‘.gm.{d. hm ‘moR>çmV ‘moR>m YZnyUmªH$ ‘c’ Amho. Á¶mZo ‘a’ d ‘b’ ¶m XmoÝhtZm ^mJ OmVmo.H$moU˶mhr XmoZ g§»¶m§À¶m‘.gm.{d bm ‘hÎm‘ gmYmaU {d^mOH$ (GCD) åhUVmV.40A{U 735 ¶m§Mm ‘.gm.{d H$mT>ʶmÀ¶m CXmhaUmMm {dMma H$am Amåhr ¶mnydr©MAd¶d nÜXVrZo ‘.gm.{d. H$mT>ʶmMm Aä¶mg Ho$bobm AmhoAmVm AmnUm XmoZ g§»`mMm _.gm.{d. wŠbrS>À`m ^mJmH$ma AëJmoar`_Zo H$mTy>
¶m nm¶ar‘ܶo Á¶mAµWr© ~mH$s eyݶ Amh|, _gm{d hm nm`ar 4 ^mOH$ Amho.
i,e 40 Am{U 735 ¶m§Mm ‘.gm.{d 5 Amho.
à¶ËZ H$am: 735 Am{U 40 ¶m§À¶m Ad¶dm§Mr ¶mXr H$ê$Z hm {ZH$mb Vwåhr nS>VmiyZ nmhÿ eH$Vm
CXmhaU 2: 513 Am{U 783 ¶m§Mm ‘. gm.{d. H$mT>m.
nm¶ar 1: a= 783 A{U b=513 ¿¶m nm¶ar 2: a= 513 A{U b=270 ¿¶m
wŠbrS>Mm ^mJmH$ma boå_m Imbrb à_mUo Xe©{dVmV
{Q>n:(a,b.) åhUOoa Am{U b Mm_.gm.{d
a=15 A{U b=10 Mm {dMma H$am.
¶oWo, q = 1, r = 5
¶w[³bS>À¶m boå‘mZwgmaa = (b x q) + r15 = (10 x 1) + 5
5 ) 10 ( 2 -10 00
¶oWo, q = 2, r = 0
¶w[³bS>À¶m boå‘mZwgmaa = (b x q) + r10 = (10x 1) + 5
nm¶ar 3 :
10 )15( 1 -10 5
nm¶ar 4: a=10 A{U b=5 ¿¶m
513 ) 783 ( 1
-513
270
¶oWo, q = 1, r = 270,
¶wp³bS>À¶m boå‘mZwgma10 By Euclid's lemma,a = (b × q) + r
40 = (15 × 2) + 10
270 ) 513 ( 1
- 270
243
¶oWo, q = 1, r = 243,
¶wp³bS>À¶m boå‘mZwgma10 By Euclid's lemma,a = (b × q) + r
40 = (15 × 2) + 10513 = (270 x 1) + 243
AëJmoarW‘ hr ñnï> ì¶m»¶m Ho$boë¶mnm¶è¶m§Mr loUr Amho, Or CXmhaUogmoS>{dʶmMr nÜXV XoVo.
nm¶ar 1: 40) 735(18 -40 335 -320 15
¶oWo, q = 18, r = 15
¶w[³bS>À¶m boå‘mZwgmaa = (b x q) + r735 = (40 x 18) + 15
15 )40( 2 -30 10
¶oWo, q = 2, r = 10
¶w[³bS>À¶m boå‘mZwgmaa = (b x q) + r40 = (15 x 2) + 10
a=40 Am{U b=15 Mm {dMma H$amnm¶ar 2 :40 Am{U 735 ¶m§Mm {dMma H$am.
783 = (513 x 1)+ 270
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Real Numbers 59
~mH$s eyݶ ¶oB©n¶ªV hr {H«$¶m nwT>o Mmby R>odm. ¶m nm¶ar‘ܶo ^mOH$ (eyݶ ahrV~mH$s).hm {Xboë¶m YZ nyUmªH$mMm ‘.gm.{d. Amho.
27 ) 243 ( 9
-243
00
nm¶ar 3: a=270 A{U b=243 ¿¶m nm¶ar 4: a= 243 A{U b=27¿¶m
243 ) 270 ( 1
-243
27
¶oWo, q = 1, r = 27,
¶wp³bS>À¶m boå‘mZwgma10 By Euclid's lemma,a = (b × q) + r
40 = (15 × 2) + 10
¶oWo, q = 9, r = 0,
eodQ>Mr ewݶahrV ~mH$s 27 Amho783 Am{U 513 Mm ‘.gm.{d.
27 Amho270 = (243 x 1) + 27
nm¶ar 1 : 'x ' Am{U 'y ' bm ¶wp³bS>Mm boå‘m bmJyHo$ë¶mZo
x = (y × q) + r, 0 r < y
OoWo q hm mJmH$ma Am{U 'r' hr ~mH$s Amho.
nm¶ar 2 :Oa r = 0, Va y hm x Am{U y Mm ‘.gm.{d. Amho.
Oa r 0, Va 'y ' Am{U 'r ' bm ¶wp³bS>Mm boå‘m bmJy H$am.
nm¶ar 3 :
ñnîQ>rH$aUmË‘H$ CXmhaUo
CXmhaUo:1: ^mJmH$ma AëJ°marW‘À¶m ‘XVrZo 455 Am{U 42 bm ^mJ OmUmar ‘moR¶mV ‘m oR >r g§»¶m H$mT>m.
CH$b :i) 455 ¶m ‘moR²>¶m nyUmªH$mnmgyZ gwadmV H$am
ii 42 35 Mm {dMma H$am. iii 35 7 Mm {dMma H$am.
35)42(135
7
7)35(535
00
42 = (35 × 1) + 7 35 = (7 × 5) + 0
{dMma H$am& XmoZ g§»¶mÀ¶m ‘.gm.{d {df¶r H$m¶KS>Vo Oa* H$moUmVrhr EH$ g§»`m eyÝ` AgVo* XmoÝhr g§»`m eyÝ` AgVmV
42 )455 (10 420 3542)455 (10 quotient
^mJmH$ma
~mH$s
42)455 (10 quotient
gd© gmYmaUnUo, ypŠbS>M ^mJmH$ma AëJmoarW_ dmnê$Z x > y Agboë`m x Am{U y `m XmoZ YZ nyUmªH$mMm_.gm.{d Imbrb nm¶è¶m‘ܶo {_i{dVm oVmo.±
{Q>n: Oa ^mOH$ hm ^mÁ¶mMm Ad¶d AgobVa eodQ>Mr ~mH$s eyݶ ¶oVo. eodQ>À¶m nm¶arnydu¶oUmar eyݶ ahrV ~mH$s hr ‘.gm.{d. AgVo.
455 = (42 × 10) + 35 (¶wp³bS>À¶m boå‘mZwgma)
à¶ËZ H$am : ¶m KQH$mÀ¶m gwadmVrbmMMm© Ho$bobo ‘|T>am§À¶m g§»¶oMo H$moS>ogmoS>dm.
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Real Numbers 60
[455,42] Mm ‘.gm.{d = [ 42,35 ] Mm ‘.gm.{d = [ 35, 7] Mm ‘.gm.{d.=7455 Am{U 42 bm ^mJ OmUmar ‘moR>çmV ‘moR>r g§»¶m 7 Amho.
CXmhaU 2: à˶ oH $ YZ g‘ n yUm ªH $ 2q ñdénmV AgVm o Am{U à˶oH $ YZ {df‘ n yUm ªH$2q + 1 ñdénmV AgVmo ho XmIdm; OoWo q hr nyU© g§»¶m Amho.
CH$b : (i) a hr g‘ YZ nyUmªH$ Amho Ago ‘m§Zy a Am{U b gmR>r ^mJmH$ma AëJm°arW‘ bmJy H$am, OoW o b=2 Amho.
a = (2 × q) + r OoW o 0 r < 2
a = 2q + r OoW o r = 0 qH$dm r = 1
Á¶mAWu 'a' hm g‘ YZ nyUmªH$, Amho ˶mAWu ‘a’. bm 2 Zo ^mJ OmVmor = 0 a = 2q + 0 = 2q
åhUyZ a = 2q Ooìhm ‘a’ hm g‘ YZ nyUmªH$ Amho.ii) 'a' hm {df‘ YZ nyUmªH$ Amho Ago ‘m§Zy. a Am{U b gmR>r ^mJmH$ma AëJm°arW‘ bmJy H$é, OoW o b = 2 Amho.
a = (2 × q) + r OoW o 0 r < 2
a = 2q + r OoW o r = 0 qH$dm r = 1
¶oWo, r 0 ( a hr g‘ Zmhr)r = 1
a = 2q + 1
åhUyZ, a = 2q + 1 Ooìhm ‘a’ hm {df‘ nyUmªH$ Amho.CXmhaU 3$ : H$m§hr 'm' nyUmªH$mgmR>r H$moU˶mhr YZ nyUmªH$mMm KZ hm EH$ Va 9m, 9m + 1 qH$dm9m + 8 ¶mn¡H$s EH$ AgVmo ho ¶wp³bS>Mm ^mJmH$ma boå‘m dmnéZ XmIdm.CH$b : a Am{U b ho XmoZ YZ nyUmªH$ AmhoV Ago ‘m§Zy Am{U a > b
a = (b × q) + r OoWo q Am{U r YZ nyUmªH$ Am{U 0 r < b
b = 3 ‘m§Zy. ( Oa 9 bm 3 Zo JwUbo Va nyU© YZ g§»¶m {‘iVo.) a = 3q + r OoWo 0 r < 3
(i) Oa r = 0, a = 3q (ii) Oa r = 1, a = 3q + 1 (iii) Oa r = 2, a = 3q + 2
¶m KQ>Zm§À¶m KZm§Mm {dMma H$am.KQ>Zm : (i) a = 3q
a3 = (3q)3 = 27q3 = 9(3q3) = 9m OoW o 'm' hm nyUmªH$ Amho Am{U m=3q3
KQ>Zm : (ii) a = 3q + 1a3 = (3q + 1)3 [(a + b)3 = a3 + b3 + 3a2b + 3ab2]
= 27q3 + 1 + 27q2 + 9q = 27q3 + 27q2 + 9q + 1
= 9(3q3 + 3q2 + q) + 1 = 9m + 1,
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Real Numbers 61
OoW o 'm' hm nyUmªH$ Am{U m=3q3 + 3q2 + q Amho.KQ>Zm : (iii) a = 3q + 2
a3 = (3q + 2)3 = 27q3 + 8 + 54q2 + 36q
= 27q3 + 54q2 + 36q + 8 = 9 (3q3 + 6q2 + 4q) + 8
= 9m + 8
OoW o m hm nyUmªH$ Am{U m = 3q3 + 6q2 + 4q Amho.H$moUË`mhr YZ nyUmªH$mMm KZ hm 'm' nyUmªH$mgmR>r EH$ Va 9m, 9m + 1 qH$dm 9m + 8 `mn¡H$s
EH$ AgVmoCXmhaU 4 : Oa x Am{U y ho YZ nyUmªH$ AmhoV Va x2 + y2 ho g‘ Amho na§Vw 4 Zo ^mJ OmV Zmhr
ho {gÜX H$am.
CH$b : Amåhmbm ‘m{hV Amho H$s, H$m§hr nyUmªH$ q gmR>r, H$moUVmhr {df‘ YZ nyUmªH$ 2q + 1 ñdénmVAmho.
m Am{U n ¶m H$m§hr nyUmªH$mgmR>r x = 2m + 1 Am{U y = 2n + 1 ‘m§Zy.
Amnë¶mH$S>o Amho x2 + y2
x2 + y2 = (2m + 1)2 + (2n + 1)2
x2 + y2 = 4m2 + 1 + 4m + 4n2 + 1 + 4n = 4m2 + 4n2 + 4m + 4n + 2
x2 + y2 = 4(m2 + n2) + 4(m + n) + 2 = 4{(m2 + n2) + (m + n)} + 2
x2 + y2 = 4q + 2, Ooìhm q = (m2 + n2)+(m + n)
x2 + y2 bm 4Zo ^mJ {Xbm AgVm Vr g‘ AgyZ ~mH$s 2 amhVo.x2 + y2 hr g‘ Amho na§Vw 4Zo ^mJ OmV Zmhr.
CXmhaU 5: EH$m nwñVH$ {dH«o$˶mH$S> o 28 H$ÞS> Am{U 72 B§p½be nwñVHo$ AmhoV. nwñVHo$ EH$mMAmH$mamMr AmhoV. hr nwñVHo$ doJdoJù¶m JÇ>çm ‘ܶo ~m§Ybr nm{hOoV Am{U à˶oH$ JÇ`>`mVrbnwñVH$m§Mr g§»¶m g‘mZ Agmdr. Va V¶ma Ho$boë¶m JÇ`m§Mr H$‘rVH$‘r g§»¶m {H$Vr Am{U à˶oH$JÇ`mVrb n wñVH$m §Mr g§»¶m gwÜXm H$mT >m.CH$b : H$ÞS> nwñVH$m§Mr g§»¶m = 28 B§p½be nwñVH$m§Mr g§»¶m = 72
AmnU ¶wp³bS>À¶m boå‘mZo 28 Am{U 72 Mm ‘.gm.{d. H$mT>bm nm{hOo.72 = (28 × 2) + 16
28 = (16 × 1) + 12
16 = (12 × 1) + 04
12 = (4 × 3) + 0
28 Am{U 72 ¶m§Mm ‘.gm.{d. = 4 à˶oH$ JÇ`m‘ܶo 4 nwñVHo$ AmhoV.
H$ÞS> nwñVH$m§À¶m JÇ`m§Mr g§»¶m =284 = 7
B§p½be nwñVH$m§À¶m JÇ`m§Mr g§»¶m =724
= 18
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Real Numbers 62
ñdmܶm¶ 3.11. Imbrb g§»¶m§Mm ‘.gm.{d. H$mT>ʶmgmR>r ¶wp³bS>Mm ^mJmH$ma AëJm°[aW‘ dmnam.
(i) 65 Am{U 117 (ii) 237 Am{U 81 (iii) 55 Am{U 210 (iv) 305 Am{U 793.
2. H$moUVmhr YZ, g‘ nyUmªH$ hm 4q qH$dm 4q + 2 ñdénmV Amho ho XmIdm, OoWo q hr nyU© g§»¶m Amho.
3. ¶wp³bS>Mm ^mJmH$ma boå‘m dmnéZ H$m§hr nyUmªH$ 'm' gmR>r, H$moU˶mhr YZ nyUmªH$mMm dJ© 3m qH$dm
3m + 1 ¶mn¡H$s EH$m ñdénmV AgVm o, na§Vw 3m+2. ñdénmV ZgVmo. ho XmIdm
4. VrZ H«$‘dma YZ nyUmªH$mÀ¶m JwUmH$mambm 6 Zo ^mJ OmVmo ho XmIdm.
5. 75 Jwbm~ Am{U 45 H$‘i ’w$bo AmhoV hr XmoÝhr ’w$bo Agbobo JwbXñVo (bouquets) V¶ma
H$amd¶mMo AmhoV. gd© ~Z{dboë¶m JwbXñ˶mVrb ’w$bmMr g§»`m gmaIrM Amho Va OmñVrV OmñV ’w$bo
Agboë¶m JwbXñ˶mMr g§»¶m Am{U ˶m‘Yrb ’w$bm§Mr g§»¶m H$mT>m.
6. EH$m Am¶VmH¥$Vr eoVmMr bm§~r Am{U é§Xr AZwH«$‘o 110‘r. Am{U 30 ‘r. Amho eoVmMr AJXr ~amo~a
bm§~r é§Xr ‘moOUmè¶m ‘moR>çmV ‘moR>çm girMr (rod) bm§~r H$mT>m.
A§H$J{UVm‘Yrb ‘yb^yV à‘o¶ (Fundamental Theorem of Arithmatic)Amåhmbm ‘mhrV Amho H$s, H$moUVrhr Z¡g{J©H$ g§»¶m hr ˶m§À¶m ‘yi Ad¶dmÀ¶m JwUmH$mamV {b{hbr OmVo.
CXmhaUmW© : 2 1 = 3 × 7
8 8 = 2 × 2 × 2 × 11
3 82 5 = 3 × 3 × 5 × 5 × 17
darb {dYmZmMm ì¶Ë¶mggwÜXm g˶ Amho. Vmo åhUOo,
Oa Amåhr YZ ‘yi g§»¶m§Mm JwUmH$ma Ho$bm Va Amåhmbm
Z¡g{J©H$ g§»¶m qH$dm YZ nyUmªH$ {‘iVmo.
CXmhaUmW© : 3 × 11 = 33
11 × 2 × 2 = 44 3× 3 × 3 × 7= 189
Aem àH$mao, Oa Amåhr gd© e³¶ _yi A{d^mÁ¶ g§»¶m KoVë¶m Va Amnë¶mbm gd© _ywi g§»¶m Am{U gd© ‘wi
g§»¶mMm JwUmH$ma Agboë¶m A‘¶m©{XV g§»¶m§Mm g‘yh {‘iVmo.
¶m g‘yhm‘ܶo g§¶wº$ g§»¶m gwÜXm AmhoV H$m?
‘yi g§»¶m§Mm JwUmH$ma Zgboë¶m g§¶wº$ g§»¶m AmhoV H$m?
¶mMo CÎma emoYʶmMm à¶ËZ H$é. g§¶wº$ g§»¶oMm {dMma H$am Am{U ˶m§À¶m Ad¶dmMr d¥jmH¥$Vr‘ܶo ¶mXr H$am.
‘wi g§»¶m :'P' ¶m YZ nyUmªH$mbm ‘wi g§»`m g‘OVmV Oa i) P>1 Am{Uii) P bm 1 Am{U P gmoS>yZ BVa Ad¶d ZmhrV.
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Real Numbers 63
31,416
2 15,708
2 7,854
2 3,927
3 1,309
7 187
11 17
¶mbm ‘yi Ad¶drH$aU qH$dm A{YH¥$V (canonical) Ad¶drH$aU åhUVmV.
H$m§hr g§¶wº$ g§»¶m ¿¶m Am{U ‘yi Ad¶drH$aU H$am.
Vwåhmbm AmT>iyZ ¶oB©b H$s, à˶oH$ g§¶wº$ g§»¶m hr ˶mÀ¶m ‘yi Ad¶dm§À¶m JwUmH$mamV 춺$ H$aVmV. ¶mbm
A§H$J{UVmMm ‘yb^yV à‘o¶ åhUVmV.
A§H$J{UVmÀ¶m ‘yb yV à¶o‘mMo ñnï>rH$aU nwT>rb à‘mUo Amho.
à˶oH$ g§¶wº$ g§»¶m hr ‘yi Ad¶dm§À¶m JwUmH$mamV 춺$ H$aVmV Am{U ¶oUmè¶m ‘yi Ad¶dmMm
H«$‘ gmoSy>Z ho Ad¶drH$aU A{ÛVr¶ (doJio) Amho.
bj Úm H$s, H$moU˶mhr {Xboë¶m g§¶wº$ g§»¶ogmR>r ˶m g§»¶oÀ`m ‘yi Ad¶dmMm JwUmH$ma {b{hʶmMr ’$º$ EH$
Am{U EH$M nÜXV Amho ˶mÀ¶m Ad¶dmÀ¶m H«$‘mH$S>o {deof bj {Xbo OmV Zmhr.
{Xboë¶m g§»¶oÀ¶m ‘yi Ad¶dm§Mr ¶mXr H$éZ, ˶m§Mm ‘.gm.{d Am{U b.gm.{d. ghOnUo H$mT>bm OmD$eH$Vmo.
ñnîQ >rH$aUmË‘H$ CXmhaUo
CXmhaU 1 :‘yi Ad¶drH$aU nÜXVrZo 18 Am{U 45 ¶m§Mm ‘.gm.{d Am{U b.gm.{d. H$mT >m.CH$b : 18 Am{U 45 ho ‘yi Ad¶dm§À¶m JwUmH$mamV 춺$ H$am.
18= 2 × 3 × 3 = 2 × 345= 3 × 3 × 5 = 3 × 5
2
2
18 d 45 Mm ‘.gm.{d = 3 × 3 = 9
18 d 45 Mm b.gm.{d = 3 × 3 × 2 × 5 = 90
ñ‘aU H$am : H$moU˶mhr XmoZ YZ nyUmªH$mMm ‘.gm.{d. hm g§»¶mÀ¶m g‘mB©H$ ‘yi Ad¶dmÀ¶m bhmZmV bhmZ
g§¶wº$ g§»¶m :Or g§»¶m 1 nojm ‘moR>r Amho Am{U ‘yig§»¶m Zmhr Vr åhUOoM g§¶wº$ g§»¶m
31,416 = 2 × 2 × 2 × 3 × 7 × 11 × 1731,416 = 23 × 3 × 7 × 11 × 17
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Real Numbers 64
KmVm§H$mMm JwUmH$ma AgVmo.H$moU˶mhr XmoZ YZ, nyUmªH$mMm b.gm.{d. hm g§»¶m§À¶m à˶oH$ ‘yi Ad¶dm§À¶m ‘moR>çmV ‘moR>m KmVm§H$mMmJwUmH$ma AgVmo.CXmhaU 2: ‘yi Ad¶drH$aU nÜXVrZo åhUOoM A§H$J{UVmÀ¶m ‘yb^yV à‘o¶mZo 42 Am{U 72 Mm‘.gm.{d Am{U b.gm.{d H$mT>m.
CH$b : 42 = 2 × 3 × 7 72 = 2 × 2 × 2 × 3 × 3 = 23 × 32
(42, 72) Mm ‘.gm.{d = 2 × 3 = 6
(42, 72) Mm b.gm.{d = 23 × 32 × 71 = 504
{ZarjU H$am H$s 42 × 72 = 3,024
(42, 72) Mm ‘.gm.{d. × (42, 72) Mm b.gm.{d = 6 × 504 = 3,024
42 × 72 = ‘.gm.{d.(42, 72) × b.gm.{d (42, 72)
a Am{U b, ¶m H$moU˶mhr XmoZ YZ nyUmªH$mgmR>r
(a, b) Mm ‘.gm.{d × (a, b) Mm b.gm.{d = a × b
Oa ‘.gm.{d H$mT>bobm Agob Va hm g§~§Y XmoZ YZ nyUmªH$mMm b.gm.{d H$mT>ʶmgmR>r dmnaVmV.
CXmhaU :3 ‘yi Ad¶drH$aU nÜXVrZo 344 Am{U 60 Mm ‘.gm.{d Am{U b.gm.{d gwÜXm H$mT>m.CH $b : 344 = 2 × 2 × 2 × 43 = 23 × 43
60 = 2 × 2 × 3 × 5 = 22 × 3 × 5 (344, 60)Mm ‘.gm.{d= 22
Amåhmbm ‘mhrV Amho H$s (a, b) Mm ‘.gm.{d × (a, b) Mm b.gm.{d = a × b
(a, b) Mm b.gm.{d =HCF( , )
a ba b
(344, 60) Mm b.gm.{d =344 60
3015
2 2
(344, 60) Mm b.gm.{d = 5160CXmhaU 4 : 150, 187 Am{U 203 bm ^mJë¶m Z§Va AZwH«$‘o 6,7 Am{U 11 ~mH$s amhUmar
‘moR>çmV ‘moR>r YZ nyUmªH$ g§»¶m H$mT>m.CH$b : {Xbobo Amho H$s 150 bm Amdí¶H$ g§»¶oZo ^mJ {Xbm Va ~mH$s 6 amhVo.
150 6 = 144144 bm Amdí¶H$ g§»¶oZo Zo‘H$m (nyU©nUo) ^mJ OmVmo.Amdí¶H$ g§»¶m hr 144 Mm Ad¶d Amho.˶mMà‘mUo, nm{hOo Agbobm YZ nyUmªH$ hm187 7=180 Am{U 203 11 =192. Mm Ad¶d Amho.
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Real Numbers 65
nm{hOo Agbobm YZ nyUmªH$ hm 144, 180 d 192 Mm ‘.gm.{d Amho.
‘yi Ad¶drH$aUmZwgma,
144 = 24 × 32 180 = 22 × 32 × 5 192 = 26 × 3
(144, 180, 192) Mm ‘.gm.{d = 22 × 3 = 12
åhUyZ nm{hOo Agbobm YZ nyUmªH$ 12 Amho.
150, 187 Am{U 203 bm ^mJ {Xë¶m Z§Va AZwH«$‘o 6,7 Am{U 11 ~mH$s amhUmam ‘moR>çmV
‘moR>m YZ nyUmªH$ 12 Amho.CXmhaU 5 : Ooìhm 35, 56 Am{U 91 bm ^mJ {Xbm Va à˶oH$ KQ>ZoV 7 ~mH$s amhmV
Agob Va Vr bhmZmV bhmZ g§»¶m H$mT> m.
CH$b : Oa 35, 56 Am{U 91 bm g§»¶oZo ^mJ OmV Agob Va Vr g§»¶m ¶m ‘yi g§»¶m§Mm
b.gm.{d Amho.
‘yi Ad¶drH$aUm§Zo b.gm.{d emoYm.
35 = 5 × 7 56 = 23 × 7 91 = 7 × 13
35, 56,Am{U 91 Mm b.gm.{d = 23 × 5 ×7 × 13 = 3,640
35,56 Am{U 91 bm ^mJ OmUmar bhmZmV bhmZ g§»¶m 3,640 Amho.
Á¶mAWu ~mH$s 7 amhVo, ˶mAWu nm{hOo Agbobr g§»¶m
3 ,640 + 7 = 3,647 Amho.
CXmhaU 6 : IoimÀ¶m ‘¡XmZm^modVr dVw©imH$ma ‘mJ© Amho. {ebmbm ˶m^modVr EH$ ’o$ar Mmb{dʶmgmR>r
36 {‘{ZQ> o bmJVmV Va JrVmbm ˶mM H$m‘mgmR>r 32 {‘{ZQ> o bmJVmV. Oa XmoKtZr EH$mM q~XÿVyZ
gwadmV Ho$br Am{U EH$mM doir Am{U EH$mM {XeoZ o, Va {H$Vr {‘{ZQ>mZ §Va ˶m n wÝhm EH$Ì
gwadmVrÀ¶m q~X ÿda ^oQ>Vrb?
CH$b : ho emoYʶmgmR>r Amnë¶mbm 36 Am{U 32 Mm b.gm.{d. H$mT>bm nm{hOo. (b.gm.{d. H$m?)
36 = 2 × 2 × 3 × 3 = 22 × 32 32 = 2 × 2 × 2 × 2 × 2 = 25
b.gm.{d. (36, 32) = 25 × 32 = 32 × 9
b.gm.{d. (36, 32) = 288
{ebm Am{U JrVm nwÝhm gwadmVrÀ¶m q~Xÿ‘ܶo 288 {‘{ZQ>mZ§Va oQ>VmV.
CXmhaU 7: (7 × 11 × 13 + 13) hr g§¶wº$ g§»¶m Amho ho {dYmZ ñnï> H$am.
CH$b: (7 × 11 × 13) + 13 = 13 [(7 × 11) + 1] = 13[77 + 1] = 13 × 78
hr g§¶wº$ g§»¶m Amho.
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Real Numbers 66
ñdmܶm¶ 3.21. Imbrb à˶oH$ g§»¶m hr ‘yi Ad¶dm§Mm JwUmH$ma Amho ho 춺$ H$am.
(i) 120 (ii) 3825 (iii) 6762 (iv) 32844
2. Oa 25025 = 2 31 41 2 3 4. . .x xx xp p p p Va p1, p2, p3, p4 Am{U x1, x2, x3, x4 Mr qH$‘V H$mT>m.
3. Imbrb nwUmªH$mZm ‘yi g§»¶m§À¶m JwUmH$mamV 춺$ H$éZ ˶m§Mm ‘.gm.{d. Am{U b.gm.{dH$mT>m.(i) 12, 15 Am{U 30 (ii)18, 81 Am{U 108
4. nyUmªH$mÀ¶m OmoS>rMm ‘.gm.{d. Am{U b.gm.{d H$mT>m Am{U (a, b) b.gm.{d.× (a, b) Mm‘.gm.{d.= a × b ho nS>VmiyZ nmhm.(i) 16 Am{U 80 (ii) 125 Am{U 55
5. Oa 52 Am{U 182 Mm ‘.gm.{d 26 Amho Va ˶m§Mm b.gm.{d H$mT>m.6. ‘yi Ad¶drH$aU nÜXVrZo 105 Am{U 1515 ¶m§Mm ‘.gm.{d. H$mT>m Am{U ˶m§Mm b.gm.{d
gwÜXm H$mT>m.7. Oa bhmZmV bhmZ g§»¶m 17 Zo dmT>{dbr Va {Vbm 520 Am{U 468 ¶m XmoÝhtZr nyU©nUo ^mJ
OmVmo Va Vr g§»¶m H$mT>m.8. EH$m Am¶VmH$ma ImobrMr bm§~r 18‘r. 72 g|.‘r. Am{U é§Xr 13 ‘r. 20 g|.‘r. Amho. ˶mbm
gma»¶mM AmH$mamÀ¶m Mm¡agmH¥$Vr ’$aem ~gdm¶À¶m AmhoV Va e³¶ Agboë¶m bhmZmV bhmZ’$aem§Mr g§»¶m H$mT>m.
9. emioVrb 8dr, 9dr Am{U 10drÀ¶m dJm©Vrb {dÚm϶mªMr g§»¶m AZwH«$‘o 48, 42 Am{U 60Amho. 8dr, 9dr Am{U 10dr À¶m {dÚm϶mªZm g‘mZar˶m nwñVHo$ dmQ>md¶mMr AmhoV. Va hdrAgboë¶m nwñVH$m§Mr H$‘rV H$‘r g§»¶m H$mT>m.
10 x, y Am{U z Zr EH$mM doir EH$mM {XeoZo dVw©imH$ma {H«$S>m§JUm^modVr Ymdm¶bm gwadmV Ho$br.gdmªZr EH$mM q~XÿVyZ gwadmV H$éZ x Zo 126 goH§$Xm‘ܶo, y Zo 154 goH§$Xm‘ܶo Am{U z Zo 231goH§$Xm‘ܶo EH$ ’o$ar nyU© Ho$br. {H$Vr doimZ§Va Vo gd©OU gwadmVrÀ¶m q~XÿV ^oQ>Vrb? ˶mMdoioV x,y Am{U z Zr {H$Vr ’o$è¶m nyU© Ho$ë¶m AgVrb?
An[a‘o¶ g§»¶m [ Irrational Numbers]Vwåhmbm IX dr À¶m dJm©‘ܶo An[a‘o¶ g§»¶mMm n[aM¶ Pmbm Amho.ñ‘aU H$am H$s, g§»¶m§Zm An[a‘o¶ g§»¶m Ago åhUVmV, Oa ˶m
pq ñdénmV {bhrVm ¶oV ZmhrV, OoW o
p Am{U q nyUmªH$ AmhoV Am{U q 0
CXm : 2, 3 , B˶mXr.AmVm 2, 3, 5 An[a‘o¶ AmhoV ho {gÜX H$é, åhUOoM gd© gmYmaUnUo p hr An[a‘o¶Amho, OoW o p hr ‘yi g§»¶m Amho.¶m g§»¶m§Mo An[a‘o¶Ëd Amåhmbm {gÜX H$aʶmnydu, Amnë¶mbm Aä¶mg H$éZ à‘o¶ {gÜX H$aUoJaOoMo Amho H$maU ˶mMr {gÜXVm A§H$J{UVmÀ¶m ‘yb yV à‘o¶mda AmYmarV Amho
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Real Numbers 67
à‘o¶ : Oa ‘yi g§»¶m p Z o a2 ^mJ OmVmo, Va a bm p Zo ^mJ OmVmo, OoW o 'a' hm YZ nyUmªH$
Amh o.
{gÜXVm : a = p1 × p2 × ........pn ‘m§Zy OoWo p1, p2.....pn ho ‘a’ Mo ‘yi Ad¶d AmhoV
XmoÝhr ~mOy§Mm dJ© H$éZ
a2= (p1 × p2 × ......× pn)2
na§Vw, p Zo a2 bm ^mJ OmVmo [ J¥hrV]
p hm p12 × p2
2 × .......pn2 Mm Ad¶d Amho.
A§H$J{UVmÀ¶m ‘yb yV à‘o¶mZwgma
p12 × p2
2 × p32 × .........×pn
2 À¶m Ad¶drH$aUm‘ܶo ‘yi ho A{ÛVr¶ (doJio) Amho.
p1, p2 .......pn‘Yrb p hm EH$ ‘yi Ad¶d Amho.Oa p = pk , k À¶m 1 nmgyZ n n¶ªVÀ¶m H$m§hr qH$‘VrgmR>r.
p1 × p2 × p3 × .....pn bm pk ^mJ OmVmo.
pk hm a bm ^mJVmo.p hm a bm ^mJVmo [ pk = p]
AmVm 2 hr An[a‘o¶ g§»¶m Amho ho {gÜX H$é.
{gÜXVm : 2 hr n[a‘o¶ g§»¶m Amho Ago g‘Oy.VoWo p Am{U q ho nyUmªH$ AemàH$mao AmT>iVmV H$s,
2 = pq OoW o, p Am{U q ho EH$‘oH$mMo gh-‘wi AmhoV.
2 q = p
XmoÝhr ~mOy§Mm dJ© H$é, 2q2 = p2
2 ho p2 bm ^mJVo (^mJ OmVmo)
2 Zo p2 bm ^mJ OmVmo (2 hm p2 bm ^mJVm o p hm g‘ Amho.
p = 2k ‘m§Zy OoW o k hm nyUmªH$ Amho.AmVm, 2q2 = (2k)2
2q2 = 4k2
q2 = 2k2 q hm g‘ Amho.
p Am{U q ho XmoÝhr g‘ AmhoV.p Am{U q Mm 2 hm gm‘mB©H$ Ad¶d Amho, ho Am‘À¶m J¥hrVmÀ¶m {déÜX Amho. åhUOoM
p Am{U q ho gh-A{d^mÁ¶ AmhoV.
Am‘Mo J¥hrV 2 hr n[a‘o¶ g§»¶m Amho MyH$ Amho.
2 hr An[a‘o¶ g§»¶m Amho.
3 hr An[a‘o¶ Agë¶mMm
{gÜX H$aʶmMm à¶ËZH$am
gô - A{d^mÁ¶
‘ a‘ Am{U ‘ b‘ ¶m XmoZ g§»¶m gh A{d^mÁ¶ AmhoV. Oa 'a' A{U "b‘ Mm ’$³V gm‘mB©H$^mOH$ 1 Amho
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Real Numbers 68
Cn{gÜXm§V 1: Oa 'a' h o bc bm ^mJVo Am{U (a, b) Mm ‘.gm.{d = 1 Va a h o c bm ^mJVo.§{gÜXVm : a ho bc bm 'k' doim (k Z ) ^mJVo Ago ‘m§Zy. ak= bc H$m§hr x, y Z,
Cn{gÜXm§V 2 : Oa XmoZ nyUmªH$mbm JwUmH$mamZo A{d^mÁ¶Zo (‘yi) ^mJ OmVmo. Va{Vbm H$‘rVH$‘r EH$mZo Var ^mJ OmVm o (^mJVm o)
CXm.: Oa p hr A{d^mÁ¶ Am{U p/ab Va p/a qH$dm p/b .
ñnï>rH$aUmË‘H$ CXmhaU o
CXmhaU 1. 5 3- hr An[a‘o¶ g§»¶m Amho ho {gÜX H$am
CH$b . 5 3 hr n[a‘o¶ g§»¶m Amho Ago g‘Oy.
5 3 = pq , OoWoo p, q z, a = 0
5 – pq = 3 5q p
q = 3
3 hr nar‘o¶ g§»¶m Amh o5q p
q hr nar‘o Amho
na§Vw 3 hr n[a‘o¶ g§»¶m Zmhr. ho Amnë¶mbm {damoYm^mg Xe©{dVo.Amnbr g‘OyV 5 3 hr n[a‘o¶ g§»¶m Amho ho MyH$ Amho.5 3 hr An[a‘o¶ g§»¶m Amho.
CXmhaU 2. 3 2 hr An[a‘o¶ g§»¶m Amho ho {gÜX H$am.CHCH$b : 3 2 hr n[a‘o¶ g§»¶m Amho Ago g‘Oy.
3 2 =pq , OoWo p, q, z , Am{U q 0
3 = 2pq
XmoÝhr ~mOy§Mm dJ© H$é, 23 =
2
2pq
3 =2
2 2. 2. 2p pqq
2 2.pq =
2
2 2 3pq
2 2.pq =
2
2 1pq
{Q>np/ab ho ab bm p Zo ^mJ OmVmo.p/a a bm p Zo ^mJ OmVmo.p/b b bm p Zo ^mJ OmVmo.p/a a bm p Zo ^mJ OmV Zmhr AgodmMVmV.
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Real Numbers 69
2 hr n[a‘o¶ g§»¶m Amh o2 2
2p q
pq hr n[a‘o¶ Amho.
na§V w 2 hr n[a‘o¶ g§»¶m Zmhr. ¶oWo Amnë¶mbm {damoYm^mg XoVo
Amnbr g‘OyV 3 2 hr n[a‘o¶ g§»¶m Amho MyH$sMo Amho.
3 2 hr An[a‘o¶ g§»¶m Amho.
ñdmܶm¶ 3.3
1. 5 hr An[a‘o¶ g§»¶m Amho ho {gÜX H$am.
2. Imbrb g§»¶m An[a‘o¶ g§»¶m AmhoV ho {gÜX H$am.
(i) 2 3 (ii)74
(iii) 3 5+ (iv) 2 5+ (v) 2 3 4-
2 2pq =
2 2
2
1p qq
2 =2 21
2p q q
q p
2 =2 212
p qpq
(vi) 52 + (v) 3-42
An[a‘o¶ g§»¶m
A§H$J{UVmMm ‘yb yV à‘o¶dmnê$Z ‘.gm. {d Am {Ub.gm.{d. H$mT>Uo
¶wp³bS>Mm ^mJmH$ma AëJmo[aW_
a = (b × q) + r, o< r < b
A§H$J{UVmMo ‘yb^yVà‘o¶
à‘o¶: Oa p hr A{d^mÁ¶ g§»¶mAmho Am{U Am{U Amho
¶yp³bS>Mm ^mJmH$ma AëJom[aW‘dmnê$Z XmoZ nyU©H$mMm ‘.gm.{dH$mT>Uo
dmñVd g§»¶m
( 2 , 3 ............)H$m¶m©dbr
p/a2 p/a
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Real Numbers 70
ñdmܶm¶ 3.1 1 (i) 13 (ii) 3 (iii) 5 (iv) 61 6. JwbXñ˶m§Mr g§»¶m = 15, à˶oH$ JwbXñ˶m‘Yrb µ’w$bm§Mr g§»¶m = (5+3 ) =8 7. 10 ‘r ñdmܶm¶ 3.2 1. (i) 23x 3 x 5 (ii) 3
2x 5
2x 17
(iii) 2 x 3x 72x 23 (iv) 2
2x 3 x 7 x 17 x 23
2. P1=5, P2=7, P3=11, P4=13, x1=2, x2=1, x3=1, x4=1
3. (i) ‘.gm.{d =3, b.gm.{d = 60, ‘.gm.{d =9, b.gm.{d = 324
5. 364 6. 15 ; 10, 605
7. 4,663 8. 4,290
9. 1,680
10. 1,386 go§H$XmZ§Va x 11 ’o$è`m, y 9 ’oè¶m, Z 6 ’o$è¶m
*****
CÎma o
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¶m KQ>H$m‘wio Vwåhmbm ¶m §Mo gwb^rH$aU hmoVo.
* ‘moOʶmMo ‘yb yV VËd ñnï> H$aUo.
* H«$‘doe Am{U g§doemMr ì¶m»¶m H$aUo.
* H«$‘M¶ {MÝh dmnaUo.
* H«$‘doem§À¶m g§»¶oMo gyÌ aMU o (nPr).* g§doemÀ¶m (nCr) g§»¶oMo gyÌ aMUo.
* H«$‘doe Am{U g§doem‘Yrb ’$aH$ H$mT>Uo.
* nPr Am{U nCr.dmnéZ CXmhaUo gmoS>{dUo.
* ‘yb yV ‘moOʶmMo VËd.
* H«$‘doe.
* H«$‘M¶ {MÝh.
*!
!n
rnP
n r
* g§doe
*
4
OH$m°~ ~aZm¡ëbr(1654 - 1705 A. D.)
OH$m°~ ~aZm¡ëbr ho ñdrg J{UVVk
AmhoV. ˶m§Zr Ag© H§$O|³Q>§³S>r
(’$m°ñWw‘m¡Obr 1713 A. D ‘ܶo à{gÜX)
¶m Amnë¶m nwñVH$m‘ܶo g§doe Am{U
H«$‘doe darb g§nyU© dV©dUyH$ {Xbr.
In mathematics the art of proposing a questionmust be held of higher value than solving it.
- George Cantor
H«$‘doe Am{U g§doePermutations and Combinations
!! !
nr
nCr n r! !r n r r
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72 UNIT-4
¶m KQ>H$mMr gwadmV OrdZmVrb g˶ àg§JmdéZ H$é Aä¶mgm Am{U JQ> H$éZ MMm© H$am.ñnï>rH$aU 1 :AmnU añ˶mdéZ AZoH$ àH$maMr dmhZo OmVmZm nmhVmo. à˶oH$ dmhZmda Zm|XUr g§»¶m Agbobr Z§~a ßboQ>AgVo.AmR>dU H$am, H$s à˶oH$ Z§~a ßboQ>da Imbrb ‘m{hVr AgVo.
1) amÁ¶mMo Zm§d (CXm : KA - H$Zm©Q>H$mgmR>r)2) àmXo{eH$ Q´>m§gnmoQ>© Am°{’$g g§Ho$V g§»¶m.
(05 - ~|Jbmoa - O¶ZJa RTO)3) B§J«Or ‘wimjao.4) g§»¶m AgVo (1 A§H$s Vo 4 A§H$s g§»¶m)
Vwåhmbm ‘m{hV Amho H$s, EH$m loUr‘ܶo {H$Vr dmhZm§Mr Zm|X Ho$br OmVo.? g‘Oë¶mZ§Va Vwåhr M{H$Vìhmb H$s 9999 dmhZm§Mr Zmo§X Ho$br OmVo.
Vwåhr ¶mMm H$Yr {dMma Ho$bmV H$m? H$s ¶m g§»¶m R.T.O H$Sy>Z H$em {Xë¶m OmVmV? ¶m JUVr‘ܶoJ{UVmMo H$moUVo VËd Amho?ñnï>rH$aU 2 :g‘Om H$s Amnë¶mH$S>o g§»¶m§Mm Hw$byn Agbobr gwQ>Ho$g Amho. g§»¶m Hw$bwnmda VrZ MmHo$ AgyZ à˶oH$MmH$mda 0 nmgyZ 9 Aem 10 A§H$m§Mr Zm§do AgVmV. Hw$bwn CKS>Vmo, Oa VrZ {deof A§H$ R>am{dH$ ‘m§S>UrVaMbo Va qH$dm nwÝhm-Z KoVm H«$‘mV KoVbo Va. g‘Om Vwåhr g§»¶m§Mm H«$‘ {dgabobm Amho Ago ‘m§Zy. hmHw$bwn CKS>m¶Mm Agob Va {H$Vr VrZ A§H$s g§»¶m§Mo H«$‘ Vwåhr Vnmgmdo? ¶m àíZmMo CÎma XoʶmgmR>rAmåhmbm 3 A§H$s g§»¶m§Mr gd© ¶mXr H$amdr bmJob. na§Vw ¶mgmR>r ^anya doi bmJVmo. ¶mH$arVm H$moUVrhrJ{UVr ¶wº$s Amho H$m Or e³¶ Agboë¶m g§»¶m§Mr ‘m{hVr {‘i{dʶmg ‘XV H$aVo.
¶m KQ>H$mV AmnU H$mhr ‘yb yV ‘moOʶmMo V§Ì Aä¶mgy Oo Amnë¶mbm darb àg§JmVrb CXmhaUm§MrCH$b H$mT>ʶmg ‘XV H$aVmV.
n{hbr nm¶ar åhUOo Amåhr VËdm§Mo H$miOrnyd©H$ narjU Ho$bo nm{hOo Oo A˶§V ‘yb^yV Aem‘moOʶmÀ¶m Aä¶mgmMo V§Ì Amho. ‘moOUo hm ¶m KQ>H$mMm ‘w»¶ {df¶ Amho. dñVy§Mm gQ> {Xbobm Amho. H$m§hr{deofVo:À¶m AmYmao CngQ>mV ‘m§S>Uo qH$dm H$m§hr {deofVoÀ¶m AmYmao CngQ>m§Mr {ZdS> H$aʶmMo H$m¶© {Xbo Amho?‘yb^yV ‘moOʶmMo VËd : (Fundamental Principle of Counting)Imbrb ñnï>rH$aUo Aä¶mgm.CXmhaU 1 : AmH¥$VrV XmI{dë¶mà‘mUo VrZ ~mhþë¶m AmhoV.
˶mn¡H$s XmoZ aH$mݶm‘ܶo R>odm¶À¶m AmhoV.Va {H$Vr àH$mao ˶m§Mr ‘m§S>Ur Ho$br OmD$ eH$Vo? ho AmnU H$go ‘moOy eH$Vmo?n{hbr Am{U Xþgar ~mhþbtMr {ZdS> H$aʶmMr d¥jmH¥$Vr Xe©{dbobr Amho Vrnmhm.
KA05EV4007
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Permutations and Combinations 73
¶m AmH¥$VrdéZ AmnU Agm {ZîH$f© H$mTy> H$s, n{hë¶m ~mhþbrMr {ZdS> 3 doJdoJù¶m àH$mao Am{U à˶oH$n{hë¶m {ZdS>rbm Xþgar ~mhþbr XmoZ doJdoJù¶m àH$mao {ZdS>br OmVo.˶m‘yio EHy$U 6 àH$ma AmhoV
VrZ n¡H$s XmoZ ~mhþë¶m§À¶m ‘m§S>UrÀ¶m EHy$U àH$mam§Mr g§»¶m 3 × 2 =6 àH$mao ho 6 doJdoJio àH$maImbrbà‘mUo Xe©{dbobo AmhoV.
CXmhaU 2 : EH$m ‘wbmH$S>o 2 n±Q> Am{U 4 eQ>© AmhoV. Vmo n±Q> Am{U eQ>© ¶m§À¶m OmoS>çm {H$Vr àH$mao n[aYmZ(Kmby) H$é eHo$b?CH$b : n±QMr {ZdS> H$aʶmMo XmoZ àH$ma AmhoV Am{U ¶m à˶oH$ {ZdS>rgmR>r eQ>© {ZdS>ʶmMo Mma àH$ma AmhoV.XmoZ n±Q> P1 , P2 Am{U 4 eQ>© S1, S2, S3 , S4 Ago Xe©{dbobo AmhoV. n±Q> Am{U eQ>© ¶m§À¶m OmoS>çmH$aʶmMo doJdoJio àH$ma d¥jmH¥$Vr‘ܶo Imbrb à‘mUo XmI{dbobo AmhoV.
eQ>©²g
Pants
P1
P2
S ––– P S1 1 1
S ––– P S2 1 2
S ––– P S3 1 3S ––– P S4 1 4
S ––– P S1 2 1
S ––– P S2 2 2
S ––– P S3 2 3S ––– P S4 2 4VoWo EHy$U 8 àH$ma AmhoV.
Xþgè¶m eãXmV 2 × 4 = 8 àH$mao n±Q> Am{U eQ>©Mr OmoS>r H$é eH$Vmo.CXmhaU 3 : g§O¶ hm°Q>ob‘ܶo Zmï>m H$aʶmgmR>r OmVmo.nXmWm©À¶m ¶mXr‘ܶo Imbrb nXmW© Agë¶mMo Xe©{dbo Amho.
Zmï>m JmoS> Ja‘ no¶BS>br (T1) {eam (S1) H$m°’$s (H1)
Xmogm (T2) Om‘yZ (S2) Mhm (H1)
nwar (T3) ~Xm‘ XþY (H1)
nwbmd (T4)à˶oH$ àH$maMm EH$ nXmW© {ZdS>ʶmMo EHy$U {H$Vr àH$ma AmhoV?Zmï>m 4 àH$mao {ZdS>bm OmD$ eH$Vmo. ZmîQçmZ§Va JmoS>nXmW© 2 doJdoJù¶m àH$mao {ZdS>bo OmD$ eH$VmV.
4 × 2 = 8 àH$mao Zmï>m Am{U JmoS> nXmW© {ZdS>bo OmD$ eH$VmV.darb à˶oH$ 8 àH$mamgmR>r Ja‘ no¶ 3 doJdoJù¶m àH$mao {ZdS>bo OmD$ eH$Vo.
8 × 3 = 24 àH$mao g§O¶ Amnbo 3 àH$ma {ZdSy> eH$Vmo.EHy$U àH$mam§Mr g§»¶m = 4 × 2 × 3 = 24
n±Q²>g
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Oa AmnU Zmï>m T1, T2, T3 Am{U T4, d JmoS> S1, S2, Am{U Ja‘ no¶ H1, H2 Am{U H3, Ago Xe©{dboVa 24 e³¶ Agbobo àH$ma Imbrb H$moï>H$mV XmI{dbo AmhoV.
T1 S1 H1 T2 S1 H1 T3 S1 H1 T4 S1 H1
T1 S2 H1 T2 S2 H1 T3 S2 H1 T4 S2 H1
T1 S1 H2 T2 S1 H2 T3 S1 H2 T4 S1 H2
T1 S2 H2 T2 S2 H2 T3 S2 H2 T4 S2 H2
T1 S1 H3 T2 S1 H3 T3 S1 H3 T4 S1 H3
T1 S2 H3 T2 S2 H3 T3 S2 H3 T4 S2 H3
darb VrZ CXmhaUmVrb ‘m{hVr Imbrb H$moï>H$mV ^abobr Amho. H$moîQ>H$ Aä¶mgm Am{U JQ>m‘ܶo MMm©H$éZ ‘moOʶmMo VËd gwMdm. CXmhaU àH$mam§Mr g§»¶m EHy$U àH$mam§Mr g§»¶m
H¥$Vr1 H¥$Vr 2 H¥$Vr 31 3 2 -- 3 × 2 = 62 4 2 – 4 × 2 = 83 4 2 3 4 × 2 × 3 = 24
AmnU {ZîH$f© H$mTy> Am{U ‘moOʶmMo ‘yb yV VËd (FPC) qH$dm JwUmH$mamMo VËd Imbrb à‘mUo ñnï>H$é eH$Vmo.
Oa EImXr H¥$Vr 'm' doJdooJù¶m àH$mao Ho$br OmVo Am{U n{hë¶m H¥$VrÀ¶m à˶oH$ g§JV àH$mamer Xþgar H¥$Vr
(n{hë¶m H¥$VrnmgyZ ñdV§Ì) 'n' doJdoJù¶m àH$mao Ho$br OmD$ eH$Vo Va XmoÝhr H¥$˶m EH$mZ§Va EH$ ¶mà‘mUo
(m × n) àH$mam§À¶m g§»¶oZo Ho$ë¶m OmVmV.darb VËd H$moU˶mhr ‘¶m©{XV g§»¶oÀ¶m KQ>ZogmR>r aMbo OmD$ eH$Vo.
VrZ H¥$VrgmR>r FPC Mo ñnï>rH$aU Ago Ho$bo OmD$ eH$Vo.Oa EH$ H¥$Vr 'm' g§»¶oZo doJdoJù¶m àH$mao Ho$br OmVo. 'm' À¶m à˶oH$ doJdoJù¶m àH$mamgmR>r Xþgar
H¥$Vr 'n' g§»¶oZo doJdoJù¶m àH$mao Ho$br OmVo Am{U ¶m à˶oH$ H¥$VrgmR>r {Vgar H¥$Vr 'p' àH$mao Ho$br OmVo Vadarb {VÝhr H¥$Vr EH$mZ§Va EH$ ¶m à‘mUo (m × n × p) àH$mao Ho$ë¶m OmVmV.
AmVm AmnU ghOnUo XmoZ nojm OmñV Ho$boë¶m H¥$VrMr, ¶mXr, ‘moOUo qH$dm d¥jmH¥$Vr Z H$mT>Vm EHy$UàH$mam§Mr g§»¶m H$mTy> eH$Vmo. ¶m FPC Mo H$m§hr CXmhaUo KodyZ ñnï>rH$aU H$é¶m.
CXmhaU 1 : {1, 2, 3, 4, 5} ho A§H$ nwÝhm-nwÝhm Z KoVm {H$Vr XmoZ-A§H$s g§»¶m V¶ma hmoVmV?CH$b : {ZdS>rÀ¶m gQ>mVrb A§H$ {1, 2, 3, 4, 5} ho AmhoV.
Á¶mAWu Amnë¶mbm XmoZ A§H$s g§»¶m V¶ma H$am¶Mr Amho Voìhm XmoZ noQ>çm H$mT>m EH$m‘ܶo gwQ>o ñWmZAm{U Xþgè¶m‘ܶo XeH$ ñWmZ ¿¶m.
AmnU àW‘ EH$‘ ñWmZ Am{U Z§Va Xe‘ ñWmZ ^é.
ñnï>rH$aUmË‘H$ CXmhaUo
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1, 2, 3, 4 ho A§H$ dmnéZ EH$‘ ñWmZ 5 doJdoJù¶m àH$mao noQ>rV (box) ^abo
OmVo..
EH$‘ ñWmZ ^aë¶mZ§Va Amnë¶mH$S>o 4 A§H$ {e„H$ amhVmV. A§H$ nwÝhm-nwÝhm KoVbo
OmV ZmhrV ˶m‘wio Xe‘ ñWmZm Mr noQ>r 4 doJdoJù¶m àH$ma o ^abr OmVo.
‘yb yV ‘moOʶmMo VËd dmnéZ 5 × 4 = 20 àH$ma {‘iVmV.
1, 2, 3, 4, 5 ho A§H$ nwÝhm-nwÝhm Z KoVm 2 A§H$s g§»¶m 20 àH$mao V¶ma hmoVmV.
Oa 1, 2, 3, 4, 5 ho A§H$ nwÝhm-nwÝhm KoVbo Va Xe‘ ñWmZ gwÜXm 5 doJdoJù¶m àH$mao ^abo OmVo.
1,2,3,4,5 ho A§H$ nwÝhm-nwÝhm KodyZ 2 - A§H$s g§»¶m V¶ma H$aʶmÀ¶m EHy$U àH$mam§Mr g§»¶m =
5 × 5 = 25 àH$mao.
{Q>n : JQ> H$éZ MMm© H$am Am{U n«Ë¶jnUo 2 A§H$s g§»¶mMr ¶mXr H$éZ VnmgyZ nmhm.
CXmhaU 2 nwÝhm-nwÝhm Z KoVm 5 ñda dmnéZ {H$Vr 3- Ajam§Mo g§Ho$V V¶ma hmoVmV?
CH$b : 5 ñda a, e, i, o Am{U u ho AmhoV.
Amnë¶mbm VrZ Ajam§Mm g§Ho$V V¶ma H$am¶Mm Amho n{hbo-Aja, 5 àH$mao {ZdS>Vm ¶oVo. Xþgao Aja 4
àH$mao {ZdS>Vm ¶oVo (nwÝhm -nwÝhm Z KoVm) {Vgao Aja 3 àH$mao {ZdS>Vm ¶oVo (nwÝhm nwÝhm Z KoVm) 3 Ajam§Mo
g§Ho$V V¶ma H$aʶmÀ¶m EHy$U àH$mam§Mr g§»¶m = 5 × 4 × 3 = 60 àH$mao.
CXmhaU 3 : 0, 1, 2, 3 Am{U 4 ho A§H$ nwÝhm Z KoVm {H$Vr 3 A§H$s g§»¶m V¶ma H$aVm ¶oVmV?
CH$b : 3-A§H$s g§»¶o‘ܶo VrZ ñWmZo AmhoV-eV‘², Xe‘² Am{U EH$‘² {ZdS>rÀ¶m gQ>mVrb A§H$
{0, 1, 2, 3, 4} ho AmhoV.
eV‘² ñWmZ : eyݶ ho eV‘² ñWmZr ¶oV Zmhr H$maU ˶m‘wio 2 A§H$s g§»¶m hmoVo. åhUyZ 1, 2, 3, 4.¶m A§H$mZr eV‘² ñWmZ 4 àH$mao ^abo OmVo.
Xe‘² ñWmZ : nwÝhm-nwÝhm KoD$Z Am{U eyݶ dmnéZ Xe‘² ñWmZ 5 àH$mao ^abo OmVo.
EH$‘² ñWmZ : ho gd© A§H$ dmnéZ 5 àH$mao ^abo OmVo.
0, 1, 2, 3, 4, 5 ho A§H$ dmnéZ 3-A§H$s g§»¶m V¶ma H$aʶmÀ¶m EHy$U àH$mam§Mr g§»¶m =4 ×5 × 5 = 100 àH$mao.
CXmhaU 4 : ‘yb yV ‘moOʶmMo V§Ì dmnéZ gwQ>Ho$gMo CXmhaU (ñnï>rH$aU
2 nmZ 2 darb) gmoS>{dʶmMm à¶ËZ H$é.
CH$b : gwQ>Ho$gÀ¶m g§»¶m Hw$bynm‘ܶo VrZ A§H$ AmhoV.
0, 1, 2, 3, 4, 5, 6, 7, 8, 9 ho A§H$ dmnéZ à˶oH$
g§»¶m 10 àH$mao V¶ma Ho$br OmVo.
6 2 07 3 18 4 2
T U
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76 UNIT-4
¶oWo A§H$ nwÝhm nwÝhm gwÜXm KoVbo OmD$ eH$VmV.
g§»¶m Hw$bwnmMm g§Ho$V V¶ma H$aʶmÀ¶m EHy$U àH$mam§Mr g§»¶m 10 × 10 × 10 = 1000 àH$mao.˶m‘wio gwQ>Ho$gMo Hw$bwn CKS>VmZm 1000 doJdoJù¶m àH$mao Vnmgbo nm{hOo.
1. H$moUVmhr A§H$ nwÝhm Z KoVm 1, 2, 3, 4, 5, 6 ho A§H$ dmnéZ {H$Vr 3-A§H$s g§»¶m V¶ma H$aVm ¶oVmV?
2. 3, 5, 7, 8, 9, ho A§H$ nwÝhm Z KoVm ho A§H$ dmnéZ {H$Vr 3-A§H$s g‘ g§»¶m V¶ma H$aVm ¶oVmV?
3. n{hbr 10 B§p½be ‘wimjao nwÝhm-nwÝhm Z KoVm {H$Vr 3-Ajam§Mo g§Ho$V V¶ma H$aVm ¶oVmV?
4. 0 Vo 9 ho A§H$ dmnéZ Oa à˶oH$ H«$‘m§H$ 65 nmgyZ gwé hmoVmo Am{U H$moUVmhr A§H$ EH$ nojm OmñV doim
Z KoVm {H$Vr 5-A§H$s XþaÜdZr H«$‘m§H$ V¶ma H$aVm ¶oVmV?
5. Oa EH$ CÎm‘ ZmUo 3 doim CS>{dbo Va ¶oUmè¶m KQ>Zm§Mr g§»¶m H$mT>m.
6. doJdoJù¶m a§JmMo 5 P|S>o {Xbobo AmhoV. Oa à˶oH$ Bemè¶m‘ܶo EH$‘oH$mda EH$ Ago XmoZ P|S>o dmnabo Va
{H$Vr àH$mao doJdoJio Bemao V¶ma H$aVm ¶oVmV?
H«$‘doe Am{U g§doe (Permutations and Combinations)‘wb yV ‘moOʶmÀ¶m VËdmMm Aä¶mg H$aVmZm AmnU nm{hbo Amho H$s, darb gd© {Xboë¶m CXmhaUm‘ܶo H$m§hr
dñVy {Xboë¶m AmhoV. ˶mn¡H$s H$m§hr dñVy§Mr {ZdS> Ho$br Amho. AmVm, AmnU dñVy§Mr {ZdS> Am{U ‘m§S>Ur {df¶r
A{YH$ Aä¶mg H$é. H$moï>H$mV {Xbobr CXmhaUo Aä¶mgm.
ñV§ 'P' ‘Yrb n{hbo CXmhaU Am{U ñV§ 'C' ‘Yrb n{hbo CXmhaU dmMm. AmVm ˶m§Mr VwbZm H$am. hrM
nÜXV am{hboë¶m CXmhaUmgmR>r nwÝhm H$am.
A.g§. ñV§ P ñV§ C
1. Aܶj Am{U g{Md ¶m nXmgmR>r 3 bmoH$ 2 nXmgmR>r 3 C‘oXdma ñnYo©V AmhoV Va Vr nXo {H$Vr
ñnYo©V AmhoV. ˶m§Mr {ZdS> {H$Vr àH$mao àH$mao ^abr OmD$ eH$VmV.
Ho$br OmVo?
2. EH$m ‘wbrH$S>o 8 ’«$m°H$ Am{U 4 ~wQ>m§À¶m EH$m ~mJo‘ܶo 8 nm§T>ao Am{U 4 bmb Jwbm~ AmhoV. 2
OmoS>çm AmhoV. Va Vr ‘wbJr ñdV…Mm bmb Agbobr 4 ’w$bo CMbʶmMo àH$ma {H$Vr?
nmofmH$ {H$Vr àH$mao H$ê$ eHo$b?
3. TEACH ¶m eãXmVrb gd© Ajam§Mr ‘m§S>Ur MEANS ¶m eãXmVrb gd© Ajam§Mr {ZdS> {H$Vr àH$mao
{H$Vr àH$mao H$aVm ¶oVo? H$aVm ¶oVo?
à˶oH$ ñV§ mVrb CXmhaUm‘ܶo H$moUVrhr g‘mZVm Vwåhr n{hbr Amho H$m? 'P' ñV§ mVrb CXmhaUmgmR>r
Amåhmbm ‘m§S>UrMr g§»¶m H$mT>mdr bmJVo. 'C' ñV§ mVrb CXmhaUmgmR>r Amåhmbm {ZdS>rMr g§»¶m H$mT>mdr
bmJVo.
ñdmܶm¶ 4.1
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Permutations and Combinations 77
darb àH$maMr CXmhaUo gmoS>{dVmZm àW‘ AmnU Vr ‘m§S>Ur Amho qH$dm {ZdS> Amho ho H$miOrnyd©H$
AmoiIbo nm{hOo. CXmhaUmW© darb CXmhaUmVrb H$moï>H$m‘Yrb n{hbo CXmhaU g‘OyZ ¿¶m.
darb MM}déZ ho gwÜXm ñnîQ> hmoVo, P ñV§ mVrb CXmhaUm‘ܶo ‘m§S>Ur qH$dm dñVy§Mr {ZdS> qH$dm 춺$s¨Mr{ZdS> H«$‘mZo Ho$br Amho. C ñV§ mVrb CXmhaUm‘ܶo dñVy§Mr, nXmWmªMr qH$dm 춺$s¨Mr {ZdS> H«$‘mZo Ho$br Zmhr.
Aem H«$‘mZo Ho$boë¶m ‘m§S>Urbm H«$‘doe Ago åhUVmV Am{U H«$‘mMm {dMma Z H$aVm Ho$boë¶m {ZdS>rbmg§doe Ago åhUVmV.H«$‘doe (Permutation) : {ZpíMV H«$‘m‘ܶo Ho$boë¶m dñVy§À¶m JQ>mÀ¶m ‘m§S>Urbm H«$‘ Ago åhUVmV. hrH«$‘mbm ‘hËd XodyZ Ho$bobr dñVy§Mr ‘m§S>Ur Amho.
EH$mMdoir n dñVyn¡H$s EH$mMdoir r dñVy§Mm H«$‘doe hm H«$‘mZo H$moU˶mhr n KQ>H$m§À¶m gQ>m‘YyZ rKQ>H$m§Mm CngQ> KoUo Agm Amho.
'n' doJdoJù¶m dñVy‘YyZ EH$mMdoir 'r' dñVyÀ¶m H«$‘doemMr g§»¶m nPr Zo Xe©{dVmV r ng§doe (Combination) : H$moU˶mhr H«$‘m{dZm dñVy§À¶m gQ>m§Mr {ZdS> H$aUo ¶mbm g§doe Ago åhUVmV.H$moU˶mhr H«$‘mMm g‘mdoe Zgboë¶m dñVy§À¶m {ZdS>rMm àH$ma Amho.EH$mMdoir n dñVyn¡H$s EH$mMdoir r dñVy§Mm g§doe hm H$moU˶mhr H«$‘m{dZm n KQ>H$m§À¶m gQ>m‘YyZ rKQ>H$m§Mm CngQ> KoUo Agm hmoVmo.* bjmV ¿¶m {H$ gQ>m‘ܶo KQ>H$m§À¶m H«$‘mbm ‘hËd Zm§hr. CXm: (1,3,2) = (2,1,3)
'n' doJdoJù¶m dñVy‘YyZ EH$mMdoir 'r' g§doemMr g§»¶m, Vr nCr, Zo Xe©{dVmV OoWo r n.
A, B Am{U C. ¶m VrZ 춺$s AmhoV Ago ‘m§Zy. noQ>r{MÝh dmné¶m Am{U gd© e³¶ Agbobo n¶m©¶ {bhÿ.
nXm§gmR>r n¶m©¶ àH$ma
A.Z§ nX-1 nX-2g§»¶m
1 A B
2 A C
3 B C
KQ>Zm 1 :Oa 'A' Mr {ZdS> EH$m nXm§gmR>r Ho$br Va XþgaonX B {H$§dm C bm {Xbo OmVo.KQ>Zm 2 : Oa B Mr {ZdS> EH$m nXmgmR>r Ho$br Va XþgaonX C bm {Xbo OmVo na§Vw A bm Zmhr H$maU AB Am{UBA hr {ZdS> EH$M Amho. ˶m‘wio ho nX ^aʶmMo VrZàH$ma AmhoV.
A, B Am{U C ¶m VrZ 춺$s AmhoV Ago ‘m§Zy. VoWoAܶj Am{U g{Md hr XmoZ nXo AmhoV. noQ>r(box)
{MÝh dmné¶m Am{U gd© e³¶ àH$ma {bhÿ.
KQ>Zm 1: Oa 'A' hm Aܶj Amho, Va 'B' ho g{MdqH$dm 'C' ho g{Md Amho.KQ>Zm 2 : Oa 'B' hm Aܶj Amho Va 'A' hm g{MdqH$dm 'C' hm g{Md Agy eH$Vmo.KQ>Zm 3 : Oa 'C' hm Aܶj Amho Va 'A' hm g{MdqH$dm B hm g{Md Agy eH$Vmo.åhUyZ {ZdS>rMo e³¶ Agbobo 6 àH$ma AmhoV.
A.Z§§§§§§§§§§§§. Aܶj g{Md1 A B2 A C3 B A4. B C5 C A6 C B
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I. Imbr ‘m§S>Ur Am{U {ZdS>rMr CXmhaUo {Xbobr AmhoV. ˶m§Mo dJuH$aU H«$‘doe Am{U g§doemÀ¶mCXmhaUm‘ܶo H$am.
1. 12 bmoH$m§À¶m JQ>m‘YyZ 5 gXñ¶ Agbobr g{‘Vr {ZdS>m.2. aH$mʶm‘ܶo nmM doJdoJù¶m {df¶mÀ¶m nwñVH$m§Mr ‘m§S>Ur H$aUo.3. 8 IwÀ¶m© AmhoV Am{U ˶mda 8 bmoH$ ~gbobo AmhoV.4. 7 춺$s¨À¶m g{‘Vr‘YyZ, EH$ Aܶj, EH$ g{Md Am{U EH$m I{OZXmamMr {ZdS> H$am¶Mr
Amho.5. ‘wbm§À¶m H$nS>çmÀ¶m XþH$mZ ‘mbH$mH$S>o 10 H$bmHw$ga Ho$bobo ’«$m°H$ AmhoV ¶mn¡H$s VrZ ’«$m°H$ nwT>À¶m
{IS>H$sda {XImì¶mgmR>r R>odm¶Mo AmhoV.6. 'ARITHMETIC' ¶m eãXmnmgyZ 3 Ajam§Mo eãX V¶ma H$am¶Mo AmhoV.7. EH$m àíZn{ÌHo$‘ܶo 12 àíZ AmhoV. {dÚm϶mªZr n{hë¶m XmoZ àíZm§Mr CÎmao {Xbr nm{hOoV na§Vw am{hboë¶m‘YyZ
8 àíZm§Mr {ZdS> Ho$br nm{hOo.8. EH$m ~aUr‘ܶo 5 H$mio Am{U 7 nm§T>ao M|Sy> AmhoV. ˶mn¡H$s 3 M|Sy> Ago CMbbo nm{hOoV H$s ˶m‘ܶo
2 H$mio, 1 nm§T>am M|Sy> Amho.9. 1,3,5,7,9 ¶mn¡H$s H$moUVmhr A§H$ nwÝhm Z KoVm {H$Vr 3 A§H$s g§»¶m V¶ma hmoVmV.
10. EH$m dVw©imH$ma H$S>çm‘ܶo 5 Mmì¶m§Mr ‘m§S>Ur Ho$bobr Amho.11. EH$m àVbm‘ܶo 7 q~Xÿ AmhoV Am{U 3 q~Xÿ Z¡H$aofr¶ AmhoV Va VrZ Z¡H$aofr¶ q~Xÿ OmoSy>Z {H$Vr {ÌH$moU
V¶ma hmoVmV.12. 10 Ioiʶm§Mm gQ> 2 ‘wbm§À¶m‘ܶo g‘mZ[a˶m {d^mJbm.
darb à˶oH$ CXmhaU ho H«$‘doemMo qH$dm g§doemMo H$m Amho? ˶mMo H$maU Úm.
à¶ËZ H$am: H«$‘doe Am{U g§doemÀ¶m 5 CXmhaUm§Mr ¶mXr H$am Am{U dJm©V MMm© H$am.
r dr Mm¡H$Q> (noQ>r) ^aʶmÀ¶m àH$mamÀ¶m g§»¶oMo gm‘mݶ gyÌ H$mT>Uo.FPC dmnéZ AmnU à˶oH$ H«$‘doemMr amer Imbrà‘mUo {bhÿ eH$Vmo :-à˶oH$ H«$‘doem‘ܶo eodQ>Mr Mm¡H$Q> ^aʶmÀ¶m g§»¶mMo àH$ma H$miOrnyd©H$ nmhm. gd© H«$‘doem‘ܶo H$m§hrgm‘mB©H$ Z‘wZo {Xbobo AmhoV. VoWo n, r À¶m {H§$‘Vr‘ܶo Am{U eodQ>Mr Mm¡H$Q> ^aʶmÀ¶m g§»¶m§À¶m àH$mam‘ܶog§~§Y Amho.
hm g§~§Y Imbrbn«‘mUo Amho.'r' Mm¡H$Q>r (noQ>çm) ^aʶmgmR>r 'n' ‘YyZ 'r' dOm H$am Am{U ˶m‘ܶo 1
{‘i{dbm Va Amåhmbm g§»¶m§Mo àH$ma {‘iVmV.i.e., (n – r + 1) bjÚm H$s 'r' dr Mm¡H$Q> ^aʶmgmR>r 'r' hmH$‘rVH$‘r 1 AgVmo ˶m‘yio r > 0
ñdmܶm¶ 4.2
55P 5 4 3 2 1
54P 5 4 3 2
53P 5 4 3
52P 5 4
51P 5
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Permutations and Combinations 79
Imbrb CXmhaUo Aä¶mgm.
1) 5P5 - Mm {dMma H$am, Amåhmbm ‘mhrV Amho H$s, eodQ>Mr Mm¡H$Q> åhUOoM 5dr Mm¡H$Q> ^aʶmMm EH$MàH$ma Amho. ho {‘i{dʶmgmR>r AmnU 5 ‘YyZ 5 dOm H$éZ ˶m‘ܶo EH$ {‘idm .i.e., (5 – 5 + 1) = 0 + 1 = 1 àH$mao.
2) 5P4 ¿¶m, ¶oWo gwÜXm Amåhmbm ‘mhrV Amho H$s, eodQ>Mr Mm¡H$Q> åhUOo 4 Wr Mm¡H$Q> aʶmMo 2àH$ma AmhoV. ho {‘i{dʶmgmR>r AmnU 5 ‘YyZ 4 dOm H$éZ ˶m‘ܶo EH$ {‘idm.i.e., (5 – 4 + 1) = 1 + 1 = 2 àH$mao.
3) 5P3 ¿¶m, ¶oWo gwÜXm Amåhmbm ‘mhrV Amho H$s, darb H$moï>H$m‘ܶo eodQ>Mr Mm¡H$Q> 3 n«H$mao aVm¶oVo. ho {‘i{dʶmgmR>r AmnU 5 ‘YyZ 3 dOm H$éZ ˶m‘ܶo EH$ {‘ibm.
i.e., (5 – 3 + 1) = 2 + 1 = 3 àH$mao.Amåhr Agm {ZîH$f© H$mTy> H$s, nPr ‘ܶo r dr Mm¡H$Q> (noQ>r) (n – r + 1) àH$mao ^abr OmD$ eH$Vo.
nwÝhm-nwÝhm Z KoVm 'n' ñnï> dñVyn¡H$s EH$mMdoir 'r' dñVy§À¶m H«$‘doem§Mr g§»¶m H$mT>Uo, OoW o 0 r n.'n' dñVyn¡H$s 'r' dñVy§À¶m H«$‘doem§Mr g§»¶m hr 'n' {Xboë¶m dñVyn¡H$s Mm¡H$Q>r‘Yrb (noQ>rVrb) 'r' OmJm ^aʶm
BVH$sM AgVo.
doJdoJù¶m 'n' dñVy Am{U 'r' ‘moH$ù¶m Mm¡H$Q>r Imbrb à‘mUo XmI{dboë¶m AmhoV.
1 2 3 r –1 r
nways
( 1)waysn ( 2)
waysn [ – 2)]n r [ –n r 1)]
ways ways
n{hbr Mm¡H$Q> 'n' doJdoJù¶m {Xboë¶m dñVy KodyZ 'n' g§»¶oÀ¶m àH$mao ^aVmV.n{hbr noQ>r ^aʶmgmR>r 'n' doJdoJio àH$ma AmhoV.
n{hbr noQ>r 'n' n¡H$s EH$m dñVyZo ^aë¶mZ§Va Amnë¶mH$S>o (n – 1) dñVy AmhoV. Á¶m nwÝhm-nwÝhm KoVm¶oV ZmhrV.
Xþgar noQ>r ^aʶmgmR>r (n – 1) doJdoJio àH$ma AmhoV.n{hë¶m XmoZ noQ>çm (Mm¡H$Q>r) ^aʶmgmR>r n (n – 1) àH$ma AmhoV (FPC)
n{hë¶m XmoZ noQ>çm ^aë¶mZ§Va Amnë¶mH$S>o (n – 2) dñV {e„H$ amhVmV.{Vgar noQ>r (n – 2) g§»¶oÀ¶m àH$mamZo ^abr OmD$ eH$Vo.
nwÝhm F.P.C dmnéZ n{hë¶m VrZ Mm¡H$Q>r n(n – 1) (n – 2) àH$mao ^aë¶m OmVmV. {Z[ajU H$am H$sà˶oH$ Mm¡H$Q> ^aë¶mZ§Va ZdrZ KQ>H$mMm n[aM¶ hmoVmo Am{U H$moU˶mhr doir KQ>H$m§Mr g§»¶m hr ^aboë¶mMm¡H$Q>r (noQ>r) À¶m g§»¶oer g‘mZ AgVo.
FPC dmnéZ H«$‘dma EH$ 'r' Mm¡H$Q>r ^aʶmMo g§»¶oMo àH$ma Imbrbà‘mUo {Xbobo AmhoV.n (n – 1) (n – 2) ............................. [n – (r – 1)]
àH$mao àH$mao, ..... àH$mao àH$mao, .....
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80 UNIT-4
'n' dñVyn¡H$s EH$mMdoir 'r' dñVy§À¶m H«$‘doemMo àH$ma nPr Zo {Xbo OmVmV. nPr = n (n – 1) (n – 2) ............................. [n – (r – 1)]
Cn{gÜXm§V : 'n' dñVyn¡H$s EH$mMdoir gd© dñVy KoʶmÀ¶m H«$‘doemMr g§»¶m hr.nPn = n (n – 1) (n – 2) ............................. [n – (n – 1)]nPn =n (n – 1) (n – 2) ............................. 1
qH$dm, nPn = n (n – 1) (n – 2) ............................. 3 2 1 ('n' Ad¶d)
H«$‘M¶ {MÝh : (Factorial notation)nmhm H$s darb amerMr COdr ~mOy hr n{hë¶m 'n' Z¡g{J©H$ g§»¶m§Àmm JwUmH$ma Amho. ho n ‘o Xe©{dVmV H«$‘M¶n! ho n Ago dmMVmV (n!)
n (n – 1) (n – 2) ............................. 3 2 1 = n!n! ho n{hë¶m n Z¡g{J©H$ g§»¶m§Mm JwUmH$ma Xe©{dVo.
4! = 1 × 2 × 3 × 4 qH$dm 4 × 3 × 2 × 13! = 1 × 2 × 3 qH$dm 3 × 2 × 12! = 1 × 2 qH$dm 2 × 1n! = 1 × 2 × 3 ..... × n qH$dm n × (n – 1) (n – 2) × .... 3 × 2 × 1
ì¶m»¶odê$Z 0! ho 1 KoVbo Amho. {Q>n : Oa n hr F$U g§»¶m qH$dm Xem§e, Agob Va n! Mr ì¶m»¶m hmoV Zmhr.
bjmV R>odm :n! hm n{hë¶m 'n' Z¡g{J©H$ g§»¶m§Mm JwUmH$ma Amho. n! = n (n – 1) (n – 2) × ...... × 3 × 2 × 1
1
n
n hr n{hë¶m 'n' Z¡g{J©H$ g§»¶m§Mr ~oarO.1
n
n = 1 + 2 + 3 + ........... + n
Imbr {Xboë¶m H«$‘M¶ {MÝhmVrb amer Aä¶mgm.n! = n (n – 1) (n – 2) × ...... × 3 × 2 × 1
(n – r)! = (n – r) (n – r – 1) (n – r – 2) × ...... × 3 × 2 × 1
(n – r + 1)! = (n – r + 1) (n – r) (n – r – 1) × ...... × 3 × 2 × 1
(n – r + 1)! = (n – r + 1) (n – r – 2) (n – r – 3) × ...... × 3 × 2 × 1
(r – 1)! = (r – 1) (r – 2) (r – 3) × ...... × 3 × 2 × 1
gd©gmYmaUnUo n! = n (n – 1) (n – 2) × ...... × 3 × 2 × 1n! = n [(n – 1) (n – 2) × ...... × 3 × 2 × 1]n! = n [(n – 1)!]
qH$dm n! = n (n – 1) (n – 2)!qH$dm n! = n (n – 1) (n – 2) (n – 3) !........ B˶mXr
CXmhaUmW©, 5! g‘Om.5! = 5 × 4 × 3 × 2 × 15! = 5 × 4!5! = 5 × 4 × 3 !5! = 5 × 4 × 3 × 2!
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Permutations and Combinations 81
ñdmܶm¶ 4.3
1. Imbrb JwUmH$mam§Mo énm§Va H«$‘M¶ ‘ܶo H$am. (i) 1 × 2 × 3 × 4 × 5 × 6 × 7 (ii) 18 × 17 ........ 3 × 2 × 1
(iii) 6 × 7 × 8 × 9 (iv) 2 × 4 × 6 × 8
2. qH$‘V H$mT>m: (i) 6! (ii) 9! (iii) 8! – 5!
(iv)7!5!
(v)12!
9! 3! (vi)30!28!
3. qH$‘V H$mT>m : (i)!
!n
n r (ii)!! !
nn r r Ooìhm n = 15 Am{U r = 12 Amho
4. 4!, 5!, 6! ¶m§Mm b.gm.{d. H$mT>m. 5. (i) Oa (n +1)! = 12 (n – 1)! Va n Mr qH$‘V H$mT>m
H«$‘M¶ {MÝh dmnê$Z npr Mo gyÌ V¶ma H$aUo
‘moOʶmÀ¶m ‘yb yV VËdmdéZ (FPC)nPr = n (n – 1) (n – 2) × .......... × (n – r + 1)
g‘rH$aUmMr COdr ~mOy (RHS) ¿¶m.n (n – 1) (n – 2) ........ (n – r + 1)
RHS ‘ܶo Z¡g{J©H$ g§»¶mMm JwUH$maCOì¶m ~mOyMo eodQ>Mo nX (n – r + 1) Amho.Oa AmnU hm JwUmH$ma 1 n¶ªV Ho$ë¶mg Amnë¶mbm H$m¶ {‘iVo? Amnë¶mbm n! ho {‘iVo. n! {‘i{dʶmgmR>rH$moUVm Á¶mXmMm Ad¶d Amnë¶mbm {bhmdm bmJob?[(n – r ) (n – r + 1) ........ 3 × 2 × 1] ho (n – r)! hmoVo.nPr = n (n – 1) (n – 2) ........ (n – r + 1)
1 2 ..... 1n
r
n n n n r n rP
.... 3 2 1
1n r n r .... 3 2 1
nPr =n!
n r ! nPr =
n!n r ! [[Oa r > 0]]
n dñVyn¡H$s H«$‘mdoemZo EH$mModoir r dñVy KoʶmÀ¶m àH$maMr g§»¶m.!
!n
rnP
n r( OoW o 0 r n )
darb gyÌ nPr gmR>r bmJy nS>Vo OoWo nwZamdVuV hmoV ZmhrV.
'n' nwÝhm-nwÝhm Z KoVm EH$mM doir 'n' doJdoJù¶m dñVyn¡H$s 'r' dñVyÀ¶m H«$‘doemMr g§»¶m.n P r Amho.
AmVm nPr À¶m {deof KQ>Zm§Mm Aä¶mg H$é.KQ>Zm 1 : Ooìhm r = 0 AgVmZm H$m¶ KS>Vo? Vo AmVm AmnU nmhÿ. Oa r = 0 Va n n¡H$s 0 dñVy§Mr ‘m§S>Ur AmnU
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82 UNIT-4
H$emàH$mao H$ê$ eH$Vmo. H$moU˶mhr dñVyMr ‘m§S>Ur Z H$aVm gd© dñVy Oemg Vem nmR>r‘mJo amhVmV Am{U
Amåhmbm ‘mhrV Amho H$s, Ago H$aʶmMr EH$M nÜXV Amho.
0!0 !
n nn
P =!!
nn B
0 1nP = CXm 100P0 = 1, 200P0 = 1, 958P0 = 1,
KQ>Zm 2 : r = nnPr = n (n – 1) (n – 2 ) × .................... × (n – r + 1)nPn = n (n – 1) (n – 2 ) × .................... × (n – n + 1)nPn = n (n – 1) (n – 2 ) × .................... × 1nPn = n (n – 1) (n – 2 ) × .................... × 3 × 2 × 1nPn = n!
gwÜXm! ! !
! 0!n
nn n n
n nP (0! = 1 hr ì¶m»¶m AmR>dm.)
CXmhaU : 1009P1009 = 1009 !, 10P10 = 10 !, 1400P1400 = 1400 !KQ>Zm 3 : r = 1
!!
nr
nn r
P 1!1 !
n nPn
1
1 !n
n nP
1 !n nP1 = n
CXmhaUo 100P1 = 100, 457P1 = 457
MMm© H$am : 5P6 ho AW©hrZ Amho. H$m?
bjmV R>odm :
nPr
!!
nn r
Oa r = 0, nP0 = 1 Va r = n Oa nPn = n! Oa r = 1 Va nP1 = n
CXmhaU 1 . qH$‘V H$mT>m : (i) 7P3 (ii) 8P5
CH$b : (i) 73
7! 7! 7 6 5 4!7 3 ! 4!
P4!
7 6 5 210
(ii) 85
8! 8! 8 7 6 5 4 3!8 5 ! 3!
P3!
8 7 6 5 4 6720
ñnï >rH$aUmË‘H$ CXmhaUo
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Permutations and Combinations 83
CXmhaU 2 : Oa 5. 4Pr = 6 .5Pr – 1 Va 'r ' H$mT>m.
CH$b :4! 5!5 6
4 ! 5 1 !r r
5! 6 5!4 !r 6 !r
14 !r
66 5 4 !r r r
(6 – r) (5 – r) = 6 r2 – 11r +24 = 0 (r – 8) (r – 3) = 0
r = {8,3} r =8 ho AW©{hZ Amho H$maU r >>>n.>
CXmhaU 3 : n! + (n + 1)! = n! (n + 2) ho {gÜX H$am.CH$b : S>mdr ~mOy LHS: n! + (n + 1)! = n! + (n + 1) n! = n! (1 + n + 1)
= n! (n + 2) = RHS (COdr ~mOy)
CXmhaU 4 : Oa 41
4
53
n
n
PP Va 'n' H$mT>m.
CH$b : S>mdr ~mOy =( 1)n n 2n 3n
( 1)n n 2n 3n5
4 34n
nn
5(n – 4) = 3n 5n – 20 = 3n 2n = 20n = 10
CXmhaU 5 : Oa 2n + 1Pn – 1 : 2n + 1Pn = 3 : 5 Va n. H$mT>m.
CH$b :2 1
12 1
35
nn
nn
PP
i.e., 5 × 2n + 1Pn – 1 = 3 × 2n – 1Pn
5. 2 1 ! 3. 2 1 !2 1 !2 1 1 !
n nn nn n
5 2 1 2 2 1 ! 3 2 1 !2 ! 1 !
n n n nn n
10 2 1 32 1 1 ! 1 !
n nn n n n n
10 (2n + 1) = 3(n + 2) (n + 1)
3n2 – 11n – 4 = 0 (3n + 1) (n – 4) = 013
n or n = 4.
Á¶mAWu n hm YZ nyUmªH$ Amho, n = 4.
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84 UNIT-4
CXmhaU 6 : (i) Oa nPn = 5040, Va 'n' H$mT>m.
CH$b : nPn = 7 × 6 × 5 × 4 × 3 × 2 × 1 = 5040
n! = 7! n = 7
(ii) Oa nP2 = 90 Va 'n' H$mT>m.
CH$b : nP2 = 90 $¶oWo AmnU XmoZ H«$‘dma g§»¶mMm JwUmH$ma 90 emoYy
n(n – 1) = 10 × 9 n = 10
(iii) Oa 11Pr = 990 Va 'r' H$mT>m.
CH$b : 11Pr = 990 11Pr = 11 × 10 × 9 r = 3
I. {H$‘Vr H$mT>m.
i) 12P4 ii)75P2 iii) 8P8 iv) 15P1 v) 38P0
2. (i) Oa nP4 = 20 nP2 Va 'n' H$mT>m
(ii) Oa 5Pr = 2 6Pr -1 Va 'r' H$mT>m
3. 1.Oa nP4 : nP5 = 1 : 2 Va 'n' H$mT>m
4. 1. Oa 9P5 + 5 9P4 = 10Pr Va 'r' H$mT>m.
H«$‘doemdarb àm¶mo{JH$ CXmhaUoCXmhaU 1 : aH$mdݶm‘ܶo 7 doJdoJir nwñVHo$ {H$Vr àH$mao ‘m§S>br OmD$ eH$VmV? {H$Vr àH$mao VrZ nwñVHo$ EH$̶oVmV?CH$b : 7 nwñVH$m§Mr ‘m§S>Ur H$am¶Mr Amho.
7P7 = 7!= 7 × 6 × 5 × 4 × 3 × 2 × 1= 5040 àH$mao.
Á¶mAWu VrZ nwñVHo$ EH$Ì ¶oVmV, ˶mAWu EH${ÌV Agbobr VrZ nwñVHo$ ho EH$ nwñVH$ Ago g‘OboOmVo.AmVm Amnë¶mH$S>o 7 nwñVHo$ - (3 EH${ÌV nwñVHo$) = 4 nwñVHo$.Am{U 4 nwñVHo$ + (1 VrZ EH${ÌV nwñVHo$ ) = 5 nwñVHo$.5 nwñVH$m§Mr ‘m§S>Ur Aer Ho$br OmVo H$s,
ñdmܶm¶ 4.4
11 99010 90
9
1 5040
2 5040
3 2520
4 840
5 210
6 42
7
Á¶mAWu bhmZmV bhmZ Ad¶d 1 Amho.
˶mAWu AmnU 1Zo ^KJ {Xbm nm{hOo.
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Permutations and Combinations 85
5P5 = 5! = 5 × 4 × 3 × 2 × 1 = 120 àH$mao.¶m 120 à˶oH$ àH$mam‘ܶo, 3 R>am{dH$ nwñVH$mMr ‘m§S>Ur 3! = 3 × 2 × 1 = 6 àH$mao hmoVo.
{ (B1 B2 B3)(B1 B3 B2), (B2 B1 B3), (B2 B3 B1), (B3 B1 B2)(B3 B2 B1) }
FPC déZ EHy$U ‘m§S>UrMr g§»¶m 5P5 × 3! = 120 × 6 = 720 àH$mao.
7 nwñVH$m§À¶m ‘m§S>UrMo àH$ma Aem [aVrZo H$s VrZ R>am{dH$ nwñVHo$ H|$ìhmhr EH${ÌV ¶oV ZmhrV
= 5040 – 720 = 4320
CXmhaU 2 : {2, 3, 5, 7, 9} ho A§H$ dmnéZ 30,000 Vo 90,000 ¶m‘ܶo {H$Vr 5 A§H$s g§»¶m V¶ma H$aVm¶oVrb.
CH$b :
.
hì¶m Agboë¶m g§»¶m 30,000 nojm ‘moR>r Am{U Vo 90,000 nojm bhmZ ¶m‘ܶo AmhoV.åhUyZ Xeghó ñWmZr ’$º$ ho {3, 5 qH$dm 7} A§H$ KoVbo OmD$ eH$VmV.˶m‘wio Xe ghó ñWmZ ’$º$ VrZ àH$mao ^abo OmD$ eH$Vo. am{hbobr 4 ñWmZo am{hboë¶m 4 A§H$mZr ^abrOmD$ eH$VmV. ho 4! àH$mao Ho$bo OmD$ eH$Vo.
30,000 Vo 90,000 ¶m‘ܶo ¶oUmè¶m EHy$U g§»¶m 3 × 4! { FPC} déZ= 3 × 4 × 3 × 2 × 1 = 72
CXmhmaU 3 : DNA aoUy‘ܶo Zm¶Q´>moOZMm aoUw hm Vi Amho Á¶mbm doJdoJio Vi AgboboA, G, T qH$dm C ho gd© OmoS>bobo AmhoV? Va nwÝhm-nwÝhm Z KoVm 3 doJdoJio AmYma (Vi) Agbob o{H$Vr àH$ma AmhoV?
CH$b : ¶oWo, n = 4 Am{U r = 3
!!
nr
nPn r
43
4! 4 3 2 1 24 ways4 3 ! 1
P àH$mao
1.'JOULE' ¶m eãXmVrb EH$ Aja EH$XmM dmnéZ gd© Ajao dmnéZ {S>³eZar AW© Z dmnaVm AW©nyU© {H$VreãX V¶ma hmoVmV?
2. 5 ‘mUgo Am{U 4 {ó¶m Aem àH$mao AmoirV ~gdm¶Mo Amho H$s g‘ ñWmZr {ó¶m AmhoV. Va Aem e³¶Agboë¶m {H$Vr ‘m§S>ʶm AmhoV?
3. 6 {ó¶m gd© 6 {dhrar ‘YyZ {H$Vr àH$mao nmUr Cngy (H$mTy>) eH$VmV.
Xe ghó ghó eV‘² Xe‘² gwQ>o
ñWmZr ñWmZr ñWmZr ñWmZr ñWmZr
3 àH$mao 4 àH$mao 3 àH$mao 2 àH$mao 1 àH$mao
(3,5 qH$dm 7
A = AS>oZmB©Z C = gm¶Q>mogmB©Z G = {OZmZmB©Z T = Wm¶‘mB©Z
ñdmܶm¶ 4.5
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86 UNIT-4
4. EH$m ñnY}V 8 {dÚm϶mªZr ^mJ KoVbm Amho. Va n{hbr VrZ ~{jgo {H$Vr àH$mao qOH$br OmD$ eH$VmV.5. XmoZ A§H$s g§»¶m§À¶m EHy$U g§»¶m H$mT>m.6. 1, 2, 3, 7, 8, 9 ho A§H$ nwÝhm Z KoVm ho A§H$ dmnéZ {H$Vr 4 A§H$s g§»¶m ~Z{dë¶m OmD$ eH$VmV.
(a) ˶mn¡H$s {H$Vr 6000 nojm bhmZ AmhoV?(b) ˶mn¡H$s {H$Vr g‘ AmhoV?(c) ˶mn¡H$s {H$VtMm eodQ> 7 Zo hmoVmo?7. XmoZ eham‘YyZ 15 ~gJmS>çm YmdVmV. EH$ 춺$s EH$m ehambm OmD$Z naV doJù¶m ~gJmS>rZo ¶oVo Va
Vr ho {H$Vr àH$mao H$é eH$Vo.'n' ñnï> dñVyn¡H$s EH$mMdoir 'r' dñVy§À¶m g§doemMr g§»¶m H$mT>Uo OoWo 0 r n.a, b, c Am{U d AjamnmgyZ ˶m§Mr ‘m§S>Ur Am{U {ZdS> H$aʶmMr Imbrb CXmhaUo {dMmamV ¿¶m.
g§doe Combinations H«$‘doe Permutationsn = 4, r = 1 n = 4, r = 1a, b, c, d a, b, c, d4C1 = 4 4P1 = 44C1 Mm à˶oH$ g§doe 1! H«$‘doe XoVmo. r = 2 ab,ac,ad,bc,bd,cd
ab,ac,ad,ba,bc,bd ca,cb,cd,da,db,dc4C2 = 6 4C2 Mm à˶oH$ g§doe 2! H«$‘doe XoVm o 4P2 = 12r = 3 abc,abd,acd,bcd abc abd bcd acd
4C2 = 6 acb adb bdc adcbac bad cbd cadbca bda cdb cdacab dab dbc daccoa dba dcb dca
4P3 = 24 àH$mao4C3 Mm à˶oH$ g§doe 3! H«$‘À¶ XoVmo.r = 4 abcd abcd bacd cabd dabc
4C4= 1 abdc badc cadb dacbacbd bcad cdba dbacadcb bdac cdab dcababdc bdca cbda dcba
4P4: 244C4 Mm à˶oH$ g§doe 4! H«$‘doe XoVmV.
gd©gmYmaUnUo,nCr Mm à˶oH$ g§doe r! H«$‘doe XoVmVnCr Mo gd© g§doe = ?
EHy$U H«$‘doem§Mr g§»¶m = r ! × nCrnPr = r ! × nCr
nCr = !
nrP
r nCr =
!! !
nn r r
'n' ñnï> dñVyn¡H$s EH$mMdoir 'r' g§doemMr g§»¶m
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Permutations and Combinations 87
nr
n!Cr! n - r !
{Q>n nPr dnCr ‘Yrb g§~§Y nCr =
!
nrP
r Zo {Xbm OmVmo.
nCr À¶m doJdoJù¶m {dñVmam§Mm Aä¶mg H$é:
1. r
!
nn
rPCr
2.!
! !n
rnC
r n r
3.1 2 ............... 3 2 1
! !n
r
n n nC
r n r
nCr À¶m H$m§hr {deof KQ>Zm§Mm Aä¶mg H$é¶m
KQ>Zm (i) : r = 0 ‘m§Zy nC0=1
Oa r = 0 Va, 0! ! 1
0! 0 1 !n n nC
n nnC0=1
CXmhaU 100C0 = 1, 500C0 = 1, 1000C0 = 1KQ>Zm (ii): r = 1 ‘m§Zy
Oa r = 1 Va, 1!
1! 1 !n nC
n = 1
1n
n nC
!
1 1n ! nC1 = n
CXmhaUo : 100C1 = 100, 200C1 = 200, 357C1 = 357
KQ>Zm (iii): r = n
Oa r = n Va,! !
! ! !0!n
nn nC
n n n n
! 1! 1n
n
nCn =
CXmhaUoo, 100C100 = 1, 789C789 = 1, 1497C1497 = 1
bjmV R>odm:
!! !
nr
nCn r r
nC0 = 1, r = 1, nC1 = n, nCn = 1
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88 UNIT-4
CXmhaU 1 : Oa 6Pr = 360 Am{U 6Cr = 15, Va 'r' H$mT>m.
CH$b : 6Pr = nCr × r !6Pr = 15 × r ! 360 = 15 × r !
360! 2415
r = 1 × 2 × 3 × 4r = 4
CXmhaU 2: nCr = nCn – r ho {gÜX H$am.
CH$b : Amåhmbm ‘m{hV Amho H$s, !C! !
nr
nr n r
.........(i)
g‘r (i) ‘ܶo r EodOr (n – r) KoVbo AgVm Amåhmbm {‘iob
!C! !
nn r
nn r n n r
!C!
nn r
nn r n n !r
!C! !
nn r
nn r r .........(ii)
g‘r (i) Am{U (ii) Mr VwbZm H$éZ Amåhr gm§Jy eH$Vmo H$s, nCr = nCn – r
CXmhaU 3 : Oa nC8 = nC12, Va n H$mT>m.
CH$b nC8 = nC12
nC8 = nCn –12n n
r n rC C
8 = n–12 n = 12 + 8 = 20.
1. qH$‘Vr H$mT>m (i) 10C3 (ii) 60C60 (iii) 100C97
2. (i) Oa nC4 = nC7 Va n H$mT>m.(ii) Oa nPr = 840, nCr = 35, Va n H$mT>m.
3. Oa 2nC3 : nC3 = 11:1, Va n H$mT>m.
4. 8C4 + 8C5 = 9C4 ho Vnmgm.
ñnï>rH$aUmË‘H$ CXmhaUo
ñdmܶm¶ 4.6
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Permutations and Combinations 89
5. 11
CC
nr
nr
nr Ooìhm 1 .r n ho {gÕ H$am.
CXmhaU 1: EH$m ‘mUgmMo 6 {‘Ì AmhoV. EH$ qH$dm EH$m nojm OmñV OUm§Zm Vmo g‘ma§ m‘ܶo {H$Vr àH$maoAm‘§ÌU XoVmo?CH$b : 6 {‘Ìm§Zm Am‘§{ÌV H$aʶmÀ¶m doJdoJù¶m g§doemMo àH$ma.(~amo~a 1......~amo~a2.....~amo~a......6)
ho 6 6 6 6 6 61 2 3 4 5 6C C C C C C Vo1 qH$dm, 2 qH$dm 6 ¶m§Zm Am‘§{ÌV H$ê$ eH$VmV.
6 6 6 6 6 61 2 3 4 5 6C C C C C C
6 + 15 + 20 + 15 + 6 + 16 6 6 6 6 6
1 2 3 2 1 0C C C C C C
6 + 15 + 20 + 15 + 6 + 1 = 63 àH$mao.CXmhaU 2 : MyH$ H$s ~amo~a ¶m 5 àíZm§À¶m gQ>m§Mr gd© ~amo~a CÎmao H$moU˶mhr {dÚm϶m©Zo {Xbr ZmhrV Am{UH$moU˶mhr XmoZ {dÚm϶mªZr gma»¶mM CÎmam§Mm H«$‘ {Xbobm Zmhr. ho e³¶ hmoʶmgmR>r dJm©Vrb OmñVrV OmñV{dÚm϶mªMr g§»¶m {H$Vr Agob? à˶oH$ àíZ MyH$ qH$dm ~amo~a ¶m XmoZ àH$mao àíZmMr CÎma XoʶmMo àH$ma
CH$b : EHy$U àH$mam§Mr g§»¶m = 2 × 2 × 2 × 2 × 2 = 32¶m 32 àH$mamn¡H$s AJXr EH$ àH$ma ~amo~a Amho.Á¶mAWu dJm©Vrb OmñVrV OmñV {dÚm϶mªMr g§»¶m = 32 – 1 = 31.
CXmhaU 3 : 4 {‘Ì EH$‘oH$mbm hmV {‘i{dVmV. Va hmV {‘i{dʶmMr g§»¶m H$mT>m.CH$b : Vo {‘Ì A, B, C Am{U D AmhoV Ago ‘m§Zy.
hmV {‘i{dʶmgmR>r XmoZ 춺$s¨Mm g‘mdoe Agbm nm{hOoV. gwadmVrbm 'A'춺$s Zo 'B' 춺$ser hmV {‘i{dbm Ago g‘Oy. ho 'B' 춺$sZo 'A' 춺$ser hmV {‘i{dʶmer gmaIoM Amho.
AB Am{U BA ho EH$M AmhohmV {‘i{dʶmMr g§»¶m H$mT>VmZm AmnU nmhVmo H$s H«$‘mbm ‘hËd Zmhr.hmV {‘i{dʶmMr g§»¶m Zoh‘r
nC2, Am{U nC2 =1
2n n
.
¶m CXmhaUm‘ܶ o n = 4.hmV {‘i{dʶmMr g§»¶m 4C2 Amho.
24
24! 4C
4 2 !2!3 2 1
2 1 26
1 àH$mao.
CXmhaU 4 : g‘ma§^mVrb à˶oH$ OU EH$‘oH$mbm hmV {‘i{dVmV. Oa EHy$U hmV {‘i{dʶmMr g§»¶m 45Amho. Va g‘ma§^mVrb 춺$s¨Mr g§»¶m H$mT>m.CH$b : g‘ma§ mVrb 춺$s¨Mr g§»¶m n ‘mZy. hmV {‘i{dʶmg Amdí¶H$ ì¶ÎH$s¨Mr g§»¶m = 2
nC2 = 45
B
CD
A
{AB, AC, AD}
{BC, BD}
C D
{CD}
C
DB
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90 UNIT-4
! 452 !2!
nn
145
2n n
n(n – 1) = 90n(n – 1) = 10 × 9n(n – 1) = 10(10 – 1)
n = 10g‘ma§ mVrb EHy$U 춺$s¨Mr g§»¶m = 10.
CXmhaU 5 : Aܶjmgh {Xboë¶m 12 춺$s‘YyZ 5 OUm§À¶m g{‘VrMr {ZdS> {H$Vr àH$mao Ho$br OmVo? CH$b : AܶjmMr {ZdS> 12 àH$mao Ho$br OmVo Am{U g{‘Vr‘Yrb BVa 4 OUm§Mr {ZdS> 11C4 àH$mao Ho$brOmVo.
Aem e³¶ Agboë¶m g{‘˶m§Mr g§»¶m = 12 × 11C4
= 12 × 330 = 3960. àH$mao
CXmhaU 6 : 8 Z¡H$aofr¶ q~Xÿ AmhoV. ho gd© q~Xÿ OmoSy>Z {H$Vr gai aofm H$mT>Vm ¶oVrb?CH$b : XmoZ q~Xÿ OmoS>bo AgVm gai aofm {‘iVo. Vo q~Xÿ A Am{U B ‘mZy.
EH$Va A q~Xÿ B q~Xÿbm qH$dm B q~Xÿ A bm OmoS>bm AgVm gai aofm {‘iVo. AB Am{U BA ho EH$M AmhoV.ho g§doemdarb CXmhaU Amho.'n' Z¡H$aofr¶ q~XÿVyZ H$mT>ë¶m OmUmè¶m gai aofm§Mr g§»¶m = nC2
Amåhmbm ‘m{hV Amho H$s, 21 12
nC n n
¶oWo, n = 8, r = 2
8C2 =1 8 8 12
8 Z¡H$aofr¶ q~Xÿ OmoSy>Z 28 gai aofm H$mT>Vm ¶oVmV.
CXmhaU 7 :10 Z¡H$aofr¶ q~Xÿ AmhoV. VrZ q~Xÿ OmoSy>Z {H$Vr {ÌH$moU aMVm ¶oVmV?CH$b : 3 Z¡H$aofr¶ q~Xÿ OmoS>bo AgVm {ÌH$moU {‘iVmo. ho q~Xÿ H$moU˶m H«$‘mZo OmoS>bo AmhoV ho {dMmamVKoVbo OmV Zmhr.
'n' Z¡H$aofr¶ q~XÿnmgyZ aMë¶m OmUmè¶m {ÌH$moUm§Mr g§»¶m = nC3.
¶oW o, n = 10, r = 3,!! !
nr
nCn r r
o
A
B C
A B
82
4
!! !
8!8 2 !2!
8
nr
nCn r r
C
Verification :
7 6!6!
82
2 28C
V mi m
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Permutations and Combinations 91
103
10! 10!10 3 !3! 7! 3!
C 10 93
84
7!7! 3 2 1 = 120
10 Z¡H$aofr¶ q~Xÿ KodyZ 3 q~Xÿ OmoS>bo AgVm 120 {ÌH$moU aMVm ¶oVmV.
n¶m©¶r nÜXV :
3!
! !n nC
n r r!
3 !3!n
n1 2 3 !n n n n
3 !n 3 2 13
1 26
n n n nC
Oa, n = 10
3
10 10 1 10 26
nC310 9 8
4
6 3= 120
CXmhaU 8: fï> ~hþ^yOmH¥$Vr ‘ܶo {H$Vr H$U© H$mT>Vm ¶oVmV?CH$b : fï>~hþ yOmH¥$Vr‘ܶo 6 {eamoq~Xÿ AmhoV n = 6
{déÜX {eamoq~XÿÀ¶m OmoS>çm gm§YyZ H$U© {‘iVmV.EHy$U aofm Am{U H$UmªMr g§»¶m = 6C2
2
12
n n nC 6
2
6 6 12
C = 15
15 aofm‘ܶo 6 ~mOy AmhoV. H$UmªMr g§»¶m = 15 – 6 = 9.
n¶m©¶r nÜXV :
H$Um©Mr g§»¶m = aMboë¶m gai aofm§Mr g§»¶m – ~hþ yOmH¥$VrÀ¶m ~mOy§Mr g§»¶m.
= nC2 – n
=1 12
n n n
2 22
n n n
2 32
n n 32
n n
n ~mOy§À¶m ~hy yOmH¥$VrÀ¶m H$UmªMr g§»¶m =3
2n n
fï>~hþ wOmH¥$Vr‘ܶ o, n = 6
H$UmªMr g§»¶m3
2n n 6 6 3
2 = 9
CXmhaU 9 : ~hþ^wOmH¥$Vr‘Yrb H$UmªMr OmñVrV OmñV (H$‘mb) g§»¶m 14 Amho Va ~mOw§Mr g§»¶m H$mT>m.CH$b : Amåhmbm ‘m{hV Amho H$s,number of diagonals 3
2n n
3141 2
n nn(n – 3) = 14 × 2 n(n – 3) = 7 × 4
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92 UNIT-4
n(n – 3) = 7(7 – 4) n = 7n¶m©¶r nÜXV :
3141 2
n n
n(n – 3) = 14 × 2 n2 – 3n – 28 = 0 n2 – 7n + 4n – 28 = 0n(n – 7) + 4(n – 7) = 0 (n – 7) (n + 4) = 0
n – 7 = 0 qH$dm n + 4 = 0n = 7 qH$dm n = – 4
'n' ho F$U Agy eH$V Zmhr.
n = 7 (gá ~hþ wOmH¥$Vr)
bjmV R> odm :
Ooìhm nmVirVrb Z¡H$aofr¶ q~XÿMr g§»¶m {Xbobr Agob Va
* gai aofm§Mr g§»¶m = 2
12
n n nC
* {ÌH$moUm§Mr g§»¶m = 3
1 26
n n n nC
* ~hþ wOmH¥$Vr‘Yrb H$UmªMr g§»¶m = 2
32
n n nC n
nmñH$bMm {ÌH$moU [Pascal Triangle]nmñH$b ãbmB©g (1623 - 1662) à{gÜX ’«|$M J{UVVk, g§ mì¶VmVk g§doemVk,, ^m¡{VH$Vk Am{UVËdkmZr AmhoV.nmñH$bZr emoYboë¶m {ÌH$moU ‘m§S>UrMo {Z[ajU H$am.XmoZ {ÌH$moUmVrb g§JV KQ>H$m§Mr VwbZm H$am.COì¶m ~mOyÀ¶m {ÌH$moUmbm nmñH$bMm {ÌH$moU Ago åhUVmV.
1C0
1C1
2C2
6C6
5C5
3C3
4C4
6C5
5C4
4C3
3C2
2C1
1C0
2C0
3C1
4C2
5C3
6C4
3C0
4C1
5C2
6C3
4C0
5C1
6C26C1
5C0
6C0
1
1
1
1
1
6
5
4
3
2
1
1
3
6
10
15
1
4
10
20
1
5
156
1
1
1
1
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Permutations and Combinations 93
1. 7 춧OZ d 4 ñda ¶mn¡H$s 3 춧OZ Am{U 2 ñda Agbobo {H$Vr eãX aMbo OmD$ eH$VmV? 2. 10 OUm§À¶m JQ>m‘YyZ 5 IoimSy>§Mr {ZdS> {H$Vr àH$mao Ho$br OmD$ eH$Vo?3. 17 IoimSy>‘YyZ 11 IoimSy>§Mr {ZdS> H$éZ {H«$Ho$Q> g§K V¶ma H$é eH$VmV, Á¶m‘ܶo 5 IoimSy>
Jmob§XmOr H$é eH$VmV? à˶oH$ g§KmV 2 Jmob§XmO Agbo nm{hOoV?4. dVw©imdarb 8 q~XÿVyZ {H$Vr (i) gai aofm (ii) {ÌH$moU H$mT>Vm ¶oVmV?5. (i) Xe ~hþ yOmH¥$Vr (ii) {de§‘~hþ^wOmH¥$Vr, {H$Vr H$U© H$mT>bo OmD$ eH$VmV?6. 44 H$U© Agboë¶m ~hþ wOmH¥$Vr‘Yrb ~mOy§Mr g§»¶m H$mT>m.
ñdmܶm¶ 4.7
Oa r = 0,nP0 = 1
H«$‘doe Am{U g§doe
‘wb^yV ‘moOʶmMoVËd (FPC)
g§doenCr
H«$‘doenPr
H«$‘M¶ gm§Ho${VH$ {MÝh n!nPr =
!( )!
nn r
OoWo 0 r nnCr =
!!( )!
nr n r
Oar = n,nPn = n!
Oa r = 1,nP1 = n
Oa r = 0,nC0 = 1
Oa r = n,nCn = 1
Oa r = 1,nC1 = n
nPr = nCr×r!
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94 UNIT-4
CÎmao
ñdmܶm¶ 4.11) 120 2) 12 3) 720 4) 336 5) 8 6) 20
ñdmܶm¶ 4.3 1) (i) 7! (ii) 18! (iii)
9!5!
(iv) 16 × 4 !
2) (i) 720 (ii) 362880 (iii) 40200 (iv) 42 (v) 220 (vi) 870 3) (i) 210 (ii) 105
4) 720 5) 3ñdmܶm¶ 4.4
1) (i) 11880 (ii) 5550 (iii) 40320 (iv) 15 (v) 12) (i) 7 (ii) 3 3) 6 4) 5
ñdmܶm¶ 4.5 1) 120 2) 2880 3) 720 4) 336 5) 90
6) (a) 180 (b) 120 (c) 60 7) 210ñdmܶm¶ 4.6
1) (i) 120 (ii) 1 (iii) 1,61,700 2) (i) 11 (ii) 7 3) 6ñdmܶm¶ 4.7
1) 25200 2) 252 3) 2200 4) (i) 28 (ii) 56 5) (i) 35 (ii) 170
6) 11 7) 720 8) (i) 186 (ii) 186 9) 3136 10) 117
*****·
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Probability 95
¶m KQ>H$m‘wio Vwåhmbm ¶m§Mo gwb^rH$aU hmoVo.
* ghO KS>Umè¶m ¶mÑpÀN>H$ à¶moJmÀ¶m AWm©Moñnï>rH$aU.
* Z‘wZm AdH$me Am{U KQ>Zm ¶m§Mr ì¶m»¶m H$aUo.
* g‘mZ g§ dzZr¶ KQ>Zm§À¶m AWm©Mo ñnï>rH$aU.
* {Xboë¶m KQ>ZoMo Z‘wZm AdH$me Am{U àmW{‘H$KQ>Zm emoYUo.
* doJdoJù¶m àH$maÀ¶m KQ>Zm§À¶m AWm©Mo ñnï>rH$aU.
* KQ>ZoÀ¶m g§ mì¶VoMr ì¶m»¶m H$aUo.l
* P(E) = 1 – P(E) ho {gÕ H$aUo.
* g§ mì¶VoÀ¶m ~oaOoMm {Z¶‘ {gÕ H$aUo.P(E1 E2) = P(E1) + P(E2)
* {Xboë¶m KQ>Zm§Mr g§ mì¶Vm H$mT>Uo.
5 g§^mì¶Vm(Probability)
Probability theory is nothing butcommon sense reduced tocalculation.
- Pierre de Laplace
* ghO KS>Umao à¶moJ (¶mÑpÀN>H$)
* Z‘wZm AdH$me
* g‘mZ g§^d{Z¶ KQ>Zm
* KQ>Zm§Mo àH$ma
* g§^mì¶VoMm AW©
* H$moQ>r KQ>Zm§Mr g§ mì¶Vm
* nañnamer Ho$di ({deof) KQ>Zm§Mrg§ mì¶Vm.
{nAar {S> b°nbogPierre de Laplace
(1749-1827, ’«$mÝg)
1812 ‘ܶo b°nbogZr gm§p»¶H$s‘YrbAZoH$ ‘wb yV {ZH$mb ñWm{nV Ho$bo.AmhoV. ˶m§Zr g§ mì¶Voda AmWmarVJ{UVr AZw‘m{ZV ¶w{º$dmX ‘m§S>bo.˶m§Zr g§ mì¶VoÀ¶m AZoH$ VËdm§Mmn[aM¶ H$ê$Z {Xbm. g§ mì¶Vm hrAZwHy$b (nmofH$) KQ>Zm§Mo ˶m§À¶mere³¶ Agboë¶m EHy$U KQ>Zm§Mo JwUmoÎmaAmho.
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96 UNIT-5
nyduÀ¶m B¶ÎmoV AmnU Aä¶mgbobo Amho H$s X¡Z§{XZ OrdZmVrb Odi Odi gd© H$mhr Oo AmnU nmhVmo qH$dmH$aVmo Vo e³¶Vm ¶m {df¶mer g§~§{YV Amho. AMwH$nUm Am{U ^{dî¶dmUr hr gwÕm gma»¶mM pñWVrV KS>UmarCXmhaUo AmhoV.
Aem KQ>Zm§Mm {dMma H$am. Imbrb {dYmZo Aä¶mgm.1. 2730k ‘ܶo nmè¶mMr KZVm 13,590 gm/c.c. Amho.2. gai CS>{dbobm M|Sy> da OmʶmgmR>r Am{U Imbr ¶oʶmgmR>r gmaImM doi KoVmo.3. g‘wÐ gnmQ>rda nmʶmMm CËH$bZ q~Xÿ 100°C Amho.4. ^maVr¶ {H«$Ho$Q> g§Kmbm dëS>© H$n qOH$ʶmMr CÎm‘ g§Yr Amho.5. ¶mdoir AmnU gy¶© J«hUmMo CÎm‘ Xe©Z Kody eH$Vmo.6. åh¡gyê$Mo AmajU {V{H$Q> H$Xm{MV ‘bm {‘iUma Zmhr.7. AmO nmD$g ¶oʶmMr OmñV g§ mì¶Vm Amho.
n{hë¶m VrZ {dYmZmnmgyZ eodQ>Mr Mma CXmhaUo H$er doJir AmhoV.n{hbr VrZ ñnï> Am{U {ZpíMV Va eodQ>Mr Mma g§{X½Y AmhoV.{dYmZo 1, 2, 3 hr ImÌrnyU© {dYmZo AmhoV Am{U 4, 5, 6, 7 hr {dYmZo ImÌrnyU© ZmhrV. (A{dídmgmW©
AmhoV)l {dYmZ EH$‘ܶo {Xbobo à¶moJ {H$Vrhr doim Ho$bo Var gmaImM {ZH$mb {‘iVmo qH$dm hm {dídmgmh© {ZH$mb
Amho.gmaImM {ddmX {dYmZ 2 Am{U 3 gmR>r bmJy nS>Vmo.
l Xþgè¶m eãXmV gy¶© J«hU nmhUo ho e³¶ qH$dm Ae³¶ Amho. {H«$Ho$Q> hm {dídmg Z R>odʶmMm Ioi Amho.EH$ CÎm‘ ’$b§XmO n{hë¶mM M|Sy>V ~mX hmoD$ eH$Vmo qH$dm EH$m CÎm‘ Jmob§XmOmbm EH$hr JS>r ~mX H$aVmAmbm Zmhr. åhUyZ g§K gm‘Zm qOHo$b qH$dm Zmhr.gmaImM {ddmX {dYmZ 6 Am{U 7 gmR>r bmJy nS>Vmo.eãX Ogo H$s "g§Yr', "g§^mì¶Vm', "e³¶Vm' ~hþYm B˶mXr EH$m R>am{dH$ KQ>Zo~Ôb A{ZpíMVVm Xe©{dVmV.
A{ZpíMVVoMo AJXr ¶mo½¶ ‘moO‘mn Zmhr, na§Vw J{UVm‘ܶo H$mhr pñWVrV Amnë¶mH$S>o KQ>ZoÀ¶m {ZpíMVVoMmgm§p»¶H$ qH$‘VrMr JUZm H$aʶmMr nÕV Amho. J{UVmÀ¶m Á¶m emIo‘ܶo A{ZpíMVVoMr ‘mno nwa{dbrOmVmV {Vbm g§^mì¶VoMm {gÕm§V Ago åhUVmV. ¶m {gÕm§VmMm ‘hËdmMm Cn¶moJ åhUOo gm§p»¶H$s‘Yrb EH$‘yb yV gmYZ Amho Am{U ¶m§À¶m Cn¶moJmMr ‘moR>r ì¶már "^m¡{VH$ {dkmZ, A{^¶m§{ÌH$s, O¡{dH$ {dkmZ, d¡Ú{H$¶emó, dm{UÁ¶ hdm‘mZmMr ^{dî¶dmUr B˶mXr ‘ܶo hmoVmo.
OmUyZ ¿¶m …g§^mì¶VoMm B{Vhmg … g§ mì¶VoÀ¶m g§H$ënZoMm {dH$mg EH$m AZmo»¶m nÕVrZo Pmbm. 1654 ‘ܶo17 ì¶m eVH$mV Ho$d{b¶a {S> ‘oao hm OwJmar H$mhr ’$mem§À¶m g‘ñ¶m KodyZ à{gÕ ’«|$M VËdkmZrAm{U J{UVVk ãbo¶go nmñH$b ¶m§À¶mH$S>o Ambm. nmñH$b ¶mZr ¶m§Mr MMm© AmUIr EH$m ’«|$MJ{UVVk {nAar S>r ’$a‘°Q>arer Ho$br Am{U ’$mem§À¶m g‘ñ¶oda VmoS>Jm emoYyZ H$mT>bm. ho H$m¶©åhUOoM "g§^mì¶Vm {gÕm§VmMr' gwadmV hmoVr. Oar g§ mì¶VoMr gwadmV OwJmamZo Pmbr, Var AmVmhr J{UVmÀ¶m emIoVrb gd© {dkmZ Am{U X¡Z§{XZ OrdZmVrb KQ>Zm‘ܶo A˶§V ‘hËdmMm Cn¶moJ Amho.
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Probability 97
BQ>brMo J{UVVk Oo H$mS>©Z (1501-1576) ¶m {df¶mda nwñVH$ {b{hbo ˶mMo Zm§d "~wH$ Am°Z JoågAm°’$ MmÝg' ho Amho. Oo ~aZmobr, nr. b°nbmg, E.‘maH$moìh Am{U E.EZ².H$mob‘moJmoaìh ¶m J{UVVkm§Zrg§ mì¶VoÀ¶m {gÕm§VmÀ¶m {dH$mgmgmR>r ¶moJXmZ {Xbo Amho. a{e¶Z J{UVVk E.EZ².H$mob‘moJmoaìhZr gQ>m§Mm{gÕm§V dmnê$Z g§ mì¶VoMm AmYw{ZH$ ‘mJ© gwM{dbm.
¶m KQ>H$m‘ܶo Amåhr g§ mì¶VoÀ¶m {gÕm§Vm{df¶r A{YH$ Aä¶mg H$ê$¶m.
KQ>Zo‘ܶo KS>Umè¶m g§YrMo Ooìhm n[aUm‘mË‘H$ n¥W…H$aU Ho$bo OmVo Voìhm ¶mbm g§ mì¶Vm Ago åhUVmV.
hr EH$ g§H$ënZm Amho Or A{ZpíMVVoMr g§»¶mË‘H$ ‘mno XoVo Am{U åhUyZ KQ>ZoV KSy>Z ¶oUmè¶m{ZpíMVVm Amho. g§ mʶmVoMo XmoZ ^mJ AmhoV.
g§ mì¶Vm
àm¶mo{JH$ g§^mì¶Vm VmpËdH$ g§ mì¶VmqH$dm qH$dm
àm¶mo{JH$ VËd g§^mì¶Vm emór¶ g§ mì¶VmOo àm¶mo{JH$ AZw^mda AmYmarV Amho. d¡km{ZH$ (emór¶) ¶w³Ë¶mda AmYmarV Amho.
¶m KQ>H$m‘ܶo AmnU g§ mìVoÀ¶m VmpËdH$VoMm Aä¶mg H$ê$¶m.g§^mì¶VoMr VmpËdH$Vm … (Theoretical approach to probability)
g§^mì¶VoÀ¶m VmpËdH$Vo‘ܶo, AmnU à˶jnUo à¶moJ Z H$aVm ^{dî¶ dV©{dʶmMm à¶ËZ H$aVmo. Agonm{hbo Jobo Amho H$s Oa à¶moJmVrb narjm§Mr g§»¶m OmñV Agob Va KQ>ZoVrb à¶moJmMr g§ mì¶Vm hr ˶mÀ¶mVmpËdH$ g§ mì¶Vo Odirb AgVo.
XmoÝhr àg§JmV AmnU KSy>Z ¶oUmè¶m {ZînÎmrer g§~§{YV Amho. à¶moJ ¶m eãXmMm AW© hr {H«$¶m Amho.Omo CÎm‘ ì¶m»¶m Ho$boVr {ZînVr qH$dm {ZH$mb XoVmo. AmnU à¶moJmMo dJuH$aU XmoZ àH$mamV H$ê$ eH$Vmo.
à¶moJ
{ZpíMV à¶moJ ghO KS>Umao à¶moJqH$dm qH$dm
^mH$sV à¶moJ g§^mdrV à¶moJ
Ooìhm gma»¶mM pñWVrV ho à¶moJ nwÝhm-nwÝhm Ho$bo AgVm VoM {ZH$mb qH$dm{ZînÎmr {ZH$mb {‘iVmo.
Ooìhm gma»¶mM pñWVrV ho à¶moJ nwÝhm-nwÝhm Ho$bo AgVm VmoM {ZH$mb qH$dm {ZînÎmr{‘iV ZmhrV.
CXmhaUo CXmhaUo
* ZmʶmMm ì¶mg ‘moOUo * ZmUo CS>{dUo* nmʶmMm CËH$bZ q~Xÿ H$mT>Uo * ’$mgm ’o$H$Uo* {dÚwV ‘§S>imVyZ dmhUmar * IoimÀ¶m nζm‘YyZ EH$
{dÚwV Ymam ‘moOUo nÎmm H$mT>Uo
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98 UNIT-5
{dkmZ Am{U A{^¶m§{ÌH$s‘ܶo gma»¶mM pñWVr‘ܶo à¶moJ nwÝhm-nwÝhm Ho$bo AgVm, Amnë¶mbm à˶oH$doirgmaIoM {ZH$mb {‘iVmV. ˶mbm {ZpíMV à¶moJ åhUVmV. J{UVm‘ܶo Amåhr ¶mÑpÀN>H$ à¶moJmer g§~{YVAmho.
¶mÑpÀN>H$ (g§ d) à¶moJ … Z¸$s {ZînÎmrMr ^{dî¶dmUr Z H$aVm ¶oUmam g§^d à¶moJ Amho. Var nU¶mÑpÀN>H$ à¶moJmVrb e³¶ Agboë¶m gd© {ZînÎmtMr ¶mXr Ho$br OmD$ eH$Vo.
hm EH$ à¶moJ Amho. Omo gma»¶mM pñWVr‘ܶo nwÝhm-nwÝhm Ho$bm Va à˶oH$doir VrM {ZînÎmr qH$dm {ZH$mb{‘iV Zmhr. na§Vw MmMUrVrb {ZînÎmr hr e³¶ Agboë¶m AZoH$ {ZînÎmrn¡H$s EH$ Amho.
à¶moJ hm ¶mÑpÀN>H$ à¶moJ AmhMo, Oa Vmo Imbrb AQ>r nS>VmiVmo.* ˶mbm EH$ nojm OmñV e³¶ {ZînÎmr AmhoV.* AJmoXaM e³¶ Agboë¶m {ZînÎmtMr ^{dî¶dmUr H$aVm ¶oV Zmhr.
¶m nyU© KQ>H$m‘ܶo Amåhr ’$º$ KSy>Z ¶oUmè¶m à¶moJm{df¶r MMm© H$aUma AmhmoV åhUyZ à¶moJ ho nX¶mÑpÀN>H$ à¶moJ Xe©{dVo.
¶oWo ghO KS>Umè¶m à¶moJmer g§~§{YV H$mhr nXo AmhoV. hr nXo Amåhmbm g§ mì¶VoMr VmpËdH$ g§H$ënZmg‘OyZ Koʶmg ‘XV H$aVmV. AmVm AmnU ¶mÑpÀN>H$ à¶moJmÀ¶m nXm§Zm Aä¶mgUma AmhmoV.
Imbrb Vº$m Aä¶mgm Am{U à˶oH$ eãX CXmhaUmgh g‘OyZ KoʶmMm à¶ËZ H$am.
nX AW© CXmhaUo
MmMUr (Trial)
{ZînÎmr
(Outcome)
AdH$me Z‘wZm
(Sample space)
Z‘wZm q~Xÿ(Sample point)
KQ>Zm (Event)
ghO KS>Umao à¶moJ H$aUo ¶mbm MmMUrAgo åhUVmV.
MmMUr‘ܶo Oo da {‘iVo ˶mbm {ZînÎmrqH$dm {ZH$mb åhUVmV. ¶mÑpÀN>H$à¶moJmVrb {ZH$mbm§Zm {ZînÎmr AgoåhUVmV.
ghO KS>Umè¶m à¶m oJm‘ܶo e³¶AgUmè¶m gd© {ZînÎmrZm Z‘wZm AdH$meåhUVmV. ho gm‘mݶnUo 'S' Zo Xe©{dVmV.
Z‘wZm AdH$memVrb à˶oH$ KQ>H$ qH$dmgXñ¶m§Zm Z‘wZm q~Xÿ åhUVmV.
¶mÑpÀN>H$ à¶moJm‘ܶo H$moUVrhr e³¶{ZînÎmr qH$dm {ZînÎmtMm g§¶moJ ¶mbmKQ>Zm åhUVmV. åhUOoM AdH$meZ‘wݶmVrb à˶oH$ CngQ>mbm KQ>ZmåhUVmV. ¶m KQ>Zm A, B, C, D ZoXe©{dVmV.
(i) ZmUo ’o$H$Uo qH$dm CS>{dUo
(ii) ’$mgm ’o$H$Uo
(i) N>mn (H), H$mQ>m (T)(ii) 1, 2, 3, 4, 5, 6
(i) S = {H, T}(ii) S = {1, 2, 3, 4, 5, 6}
(i) H Am{U T ho Z‘wZm q~Xÿ AmhoV.
(ii) 1, 2, 3, 4, 5d 6 ho Z‘wZm q~Xþ AmhoV.
(i) N>mn {‘i{dUo A = {H} H$mQ>m {‘i{dUo B = {T}4 {‘i{dUo A = {4}
(ii) g‘ g§»¶m {‘i{dUo B = {2,4, 6}‘wi g§»¶m {‘i{dUo C = {2, 3, 5}Z¡g{J©H$ g§»¶m {‘i{dUo
D = {1, 2, 3, 4, 5, 6}
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Probability 99
Amåhr Aä¶mgbobo Amho H$s, KQ>Zm hr AdH$me Z‘wݶmMm CngQ> Amho. Omo H$m§hr nmiVmo. EH$mM doirXmoZ ZmUr CS>{dʶmMo (qH$dm EH${ÌV) CXmhaU {dMmamV ¿¶m. d¥jm H¥$Vr aMyZ ¶m ¶mÑpÀN>H$ à¶moJmVrb Z‘wZmAdH$me ghOnUo {b{hVm ¶oVmV.
Imbrb d¥jmH¥$VrMo {ZarjU H$am.
H1
T1
H – H H
T – H T
H – T H
T – T T
2 1 2
2 1 2
2 1 2
2 1 2
AmVm AmnU, ghO KS>Umè¶m à¶moJmVrb {‘iUmè¶m KQ>Zm {bhy.
* XmoÝhr Zmʶmda N>mn ¶oVmo. E1 = { HH }* XmoÝhr Zmʶmda H$mQ>m ¶oVo. E2 = { TT }* n{hë¶m Zmʶmda N>mn Am{U E3 = { HT }
Xþgè¶m Zmʶmda H$mQ>m ¶oVo.* n{hë¶m Zmʶmda H$mQ>m Am{U E4 = { TH }
Xþgè¶m Zmʶmda N>mn ¶oVmo.
darb CXmhaUm‘ܶo, XmoÝhr ZmUr EH${ÌV CS>{dʶmMm ghO KS>Umam à¶moJ Amho. Z‘wZm AdH$meS = { HH, HT, TH, TT }
ghO KS>Umè¶m à¶moJmVrb à˶oH$ {ZînÎmrbm àmW{‘H$ (gmonr) KQ>Zm åhUVmV.
XmoZ ZmUr EH${ÌV CS>{dʶmÀ¶m ¶mÑpÀN>H$ à¶moJm‘ܶo HH, HT, TH, TT ¶m àmW{‘H$ KQ>Zm AmhoV.
XmoZ ZmUr EH${ÌV CS>{dʶmÀ¶m ¶mÑpÀN>H$ à¶moJm‘ܶo àmW{‘H$ KQ>Zm {edm¶ BVa H$mhr KQ>Zm gwÕm e³¶AmhoV.
* AJXr ~amo~a N>mn {‘iVmo E5 = {HT, TH}* H$‘rVH$‘r EH$ H$mQ>m {‘iVmo E6 = {HH, HT, TH}
* OmñVrV OmñV XmoZ amʶm {‘iVmV. E7 = {HT, TH, TT}
¶oWo AmnU nmhVmo H$s ¶mÑpÀN>H$ à¶moJmer g§~§YrV XmoZ qH$dm A{YH$ àmW{‘H$ KQ>Zm§Zm OmoSy>ZAmnë¶mbm KQ>Zm {‘iVmV. Aem KQ>Zm§Zm g§¶wº$ KQ>Zm Ago åhUVmV.
¶mÑpÀN>H$ à¶moJmer g§~§{YV KQ>Zm hr g§¶wº$ KQ>Zm Amho, ghO KS>Umè¶m à¶moJmer g§~§{YV XmoZ qH$dmA{YH$ àmW{‘H$ KQ>Zm§Zm OmoS>ë¶mZo hr {‘iVo.
AmnU KQ>Zm KS>Vo Ago Ho$ìhm åhUVmo?{Z:njnmVr ’$mgm CS>{dʶmÀ¶m ¶mÑpÀN>H$ à¶moJmMm {dMma H$am.Z‘wZm AdH$me S = {1, 2, 3, 4, 5, 6}
g‘ g§»¶m {‘iUmar KQ>Zm 'E' Zo Xe©{dVmV Ago ‘mZy.
¶m KQ>Zoer g§~§{YV ‘wb yV KQ>Zm 2, 4, 6 ¶m AmhoV.
MmMUrVrb {ZînÎmr 4 Amho Ago g‘Oy AmnU åhUVmo 'E' hr KQ>Zm KS>Vo ˶m MmMUr‘Yrb {ZînÎmr 3
AdH$me Z‘wZm,
S = { H1H2, H1T2, T1H2, T1T2 }
S = { HH, HT, TH, TT }n{hbo ZmUo
Xþgaoo ZmUo
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100 UNIT-5
AmhoV Voìhm AmnU åhUVmo H$s E hr KQ>Zm KS>V Zmhr.¶m CXmhaUmdê$Z, AmnU Agm {ZîH$f© H$mTy> eH$Vmo H$s KQ>Zm KS>ʶmMm AW© Imbrbà‘mUo Amho.¶mÑpÀN>H$ à¶moJmer g§~§{YV E hr KQ>Zm KS>Vo Ago åhUVmo, Oa E hr AZwHy$b Amho Ago åhUVmo, H$maU
à˶oH$ àmW{‘H$ KQ>Zm hr g§¶wº$ KQ>ZoÀ¶m ì¶m»¶oMo g‘mYmZ H$aVmV. Vo åhUOo E KQ>ZoV g‘ g§»¶m KS>VmV Am{U2, 4, 6 ¶m g‘ g§»¶oÀ¶m ì¶m»¶oMo g‘mYmZ H$aVmV.
¶m MM}À¶m {R>H$mUr, EH$m Hw$VwhbmÀ¶m Jmoï>rH$S>o AmnU bj {Xbo nm{hOo. Á¶m-Á¶mdoir AmnU¶mÑpÀN>H$ à¶moJ H$aVmo Va g§~§YrV KS>Umè¶m g§Yr g‘mZ AgVrb qH$dm ZgVrb.CXmhaUmW© …
(i) ZmUo CS>{dʶmÀ¶m à¶moJm‘ܶo N>mn Am{U H$mQ>m {‘iʶmÀ¶m g§Yr g‘mZ KS>VmV.(ii) Ooìhm ’$mgm ’o$H$bm OmVmo, Voìhm 1, 2, 3, 4, 5, 6 ho {‘iʶmÀ¶m g‘mZ g§Yr Amho.
(iii) Ooìhm 4 bmb Am{U 1 {Zim M|Sy> {nedr‘YyZ M|Sy> CMbʶmÀ¶m g‘mZ g§Yr AmhoV.na§Vw bmb M|Sy> CMbʶmÀ¶m e³¶Vm {Zù¶m M|Sy>nojm OmñV AmhoV.
CXmhaU (i) Am{U (ii) ‘ܶo à˶oH$ à¶moJm‘ܶo g‘mZ g§Yr ¶oʶmMr e³¶Vm Amho. Xþgè¶m eãXmV, à˶oH$àmW{‘H$ KQ>Zm hr g‘mZ[a˶m g§ dZr¶ KQ>Zm Amho. CXmhaU (iii) ‘Yrb a§JrV M|Sy> CMbʶmÀ¶m g‘mZ[a˶mg§ dZr¶ KQ>Zm AmhoV. VarnU bmb qH$dm {Zim M|Sy> CMbʶmÀ¶m g‘mZ[a˶m g§ dZr¶ KQ>Zm e³¶ ZmhrV.åhUyZ gd© ghO KS>Umao à¶moJ ¶m‘ܶo g‘mZ g§ dZr¶ {ZînÎmr AgVrbM Ago Zmhr. AmVm AmnU g‘mZ[a˶mg§ dZr¶ KQ>Zm§Mr ì¶m»¶m H$ê$¶m.
¶mÑpÀN>H$ à¶moJmVrb XmoZ qH$dm A{YH$ KQ>Zm ¶m g‘mZ[a˶m g§^dZr¶ KQ>Zm AmhoV Oa ˶mn¡H$sà˶oH$mbm {ZînÎmrÀ¶m g‘mZ g§Yr AmhoV.
bj Úm … ¶m KQ>H$m‘ܶo, Amåhr Ago J¥hrV Yê$ H$s, gd© à¶moJm‘ܶo g‘mZ[a˶m g§ dZr¶ KQ>Zm qH$dm{ZînÎmr AmhoV.
AmVm n¶ªV AmnU ghO KS>Umè¶m à¶moJmer g§~§{YV nXm§Mm Aä¶mg Ho$bobm Amho. AmVm AmnU KQ>ZoÀ¶mg§^mì¶VoMr ì¶m»¶m H$ê$¶m.KQ>ZoMr g§ mì¶Vm (Probability of an event)
Amåhr MMm© Ho$bobr Amho H$s, KQ>ZoMr g§ mì¶Vm hr KS>Umè¶m g§YrMr KQ>Zm n[aUm‘H$maH$nUo 춺$ H$aUohr Amho.
AmVm ¶mÀ¶mer g§~§{YV H$m§hr KQ>Zm§Mm {dMma H$am Am{U ¶m KQ>Zm KS>ʶmMr g§Yr qH$dm ¶m KQ>Zm§Mrg§ mì¶Vm H$mT>m.
ghO KS>Umao à¶moJ Ogo H$s ZmUo CS>{dUo qH$dm ’$mgm ’o$H$Uo ¶m§Mr Vwåhmbm H$ënZm Amho. Imbrb¶mÔpÀN>H$ à¶moJ Aä¶mgm.CXmhaU 1 …
* MH$Vr (V~H$S>r) da ~mU ‘maUo5 g‘mZ mJ Ho$boë¶m V~H$S>rMm {dMma H$am, Á¶mMo mJ a§J{dbobo AmhoV, 2 bmb,2 {Zio Am{U 1 {hadm Amho.Ooìhm hr V~H$S>r {’$adyZ ~mU ‘mabm OmVmo Am{U Vmo nmMn¡H$s EH$m ^mJmbmbmJVmo d V~H$S>r Wm§~Vo. à˶oH$ doir V~H$S>r {’$a{dbr AgVm ~mUmÀ¶mpñWVrMr ^{dî¶dmUr H$aUo e³¶ Zmhr.S = {r, r, b, b, g}
e³¶ Agboë¶m {ZînÎmtMr g§»¶m 5 Amho.ho n(S) = 5 Ago Xe©{dVmV.
rb
rg
b
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Probability 101
H$m§hr KQ>Zm ¶m,* Q>moH$ bmb a§JmÀ¶m ^mJmda Amho. E1 = {r, r}* Q>moH$ {haì¶m a§JmÀ¶m ^mJmda Amho. E2 = {g}* Q>moH$ {Zù¶m a§JmÀ¶m ^mJmda Amho. E3 = {b, b}* Q>moH$ {Zù¶m a§JmÀ¶m ^mJmda Zmhr. E4 = {r, r, g}
CXmhaU 2 … * XmoZ {Z:njnmVr ’$mgo EH$mMdoir CS>{dUo. Ooìhm XmoZ ’$mgo ’o$H$bo OmVmV Voìhm ˶m§Mm Z‘wZm AdH$me,
S = {(1, 1) (1, 2) (1, 3) (1, 4) (1, 5) (1, 6)(2, 1) (2, 2) (2, 3) (2, 4) (2, 5) (2, 6)(3, 1) (3, 2) (3, 3) (3, 4) (3, 5) (3, 6)(4, 1) (4, 2) (4, 3) (4, 4) (4, 5) (4, 6)(5, 1) (5, 2) (5, 3) (5, 4) (5, 5) (5, 6)(6, 1) (6, 2) (6, 3) (6, 4) (6, 5) (6, 6)}
n(S) = 6 × 6 = 36H$m§hr KQ>Zm ¶m,
* XmoZ g‘mZ A§H$ {‘iUmè¶m KQ>Zm A = {(1, 1), (2, 2), (3, 3), (4, 4), (5, 5), (6, 6)}
* XmoZ A§H$mMr ~oarO 5 ¶oUmè¶m KQ>Zm. B = P(1, 4), (2, 3), (3, 2), (4, 1)}* XmoZ A§H$mMr ~oarO 3 nojm H$‘r ¶oUmè¶m KQ>Zm. C = {(1, 1)}
AmVm AmnU Ago H$mhr ¶mÑpÀN>H$ à¶moJ Am{U KQ>Zm§Mm {dMma H$ê$¶m. ¶m KQ>Zm§Mm Z‘wZm AdH$me, AZwHy$b{ZînÎmtMr g§»¶m Am{U KQ>Zm KS>Umè¶m g§YrMr Zm|X H$moï>H$m‘ܶo Ho$br Amho. à˶oH$ CXmhaUmMm Aä¶mg H$am.
1. ZmUo CS>{dUo S = {H, T} N>mn da ¶oUo A = {H}, 2 n¡H$s 112
n(S) = 2 n(A) = 12. ’$mgm ’o$H$Uo S = {1, 2, 3, 4, 5, 6} g‘ g§»¶m A = {2, 4, 6} 6 n¡H$s 3 3
6n(S) = 6 da ¶oVmV n(A) = 35 nojm ‘moR>r g§»¶m A = {6} 6 n¡H$s 1
16
da ¶oVo n(A) = 13. {’$a˶m V~H$S>rda S = {r, r, b, b, g} Q>moH$ bmb a§JmÀ¶m A = {r, r} 5 n¡H$s 2 2
5~mU ‘maUo n(S) = 5 ^mJmda Wm§~Uo n(A) = 2Q>moH$ bmb a§Jmda A = {b, b, g} 5 n¡H$s 3
35
Wm§~V Zmhr n(A) = 34. XmoZ ZmUr EH$mM AJmoXaÀ¶m nmZmda 102 g‘mZ A§H$ A = {(1,1), (2,2), 36 n¡H$s 6 6
36doir CS>{dbr da nmhm n(S) = 36 da ¶oUo (3,3), (4,4) (5,5)(6,6)}n(A) = 6
~oarO 3 nojm A = {(1,1)} 36 n¡H$s 1136
H$‘r ¶oVo. n(A) = 1
ghO KS>Umaoà¶moJ
CXm.g§.
Z‘wZm AdH$meS
KQ>Zm AKQ>Zoer AZwHy$b
{ZînÎmr AKQ>Zm KS>ʶmMr
g§Yr
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102 UNIT-5
H$moï>H$mVrb eodQ>À¶m ñV§ mMo {ZarjU H$am. Vo KQ>ZoV KS>Umè¶m g§Yr qH$dm KQ>ZoMr g§ mì¶Vm Xe©{dVmV.g§»¶mË‘H$ qH$‘Vr H$moU˶m ñdê$nmV {b{hboë¶m AmhoV? ˶m AnyUmªH$s ñdê$nmV AmhoV. Á¶m‘ܶo A§eKQ>ZoÀ¶m AZwHy$b {ZînÎmtMr g§»¶m Am{U N>oX e³¶ Agboë¶m {ZînÎmtMr g§»¶m Xe©{dVmV.
gd© gmYmaUnUo E hr H$moUVrhr EH$ KQ>Zm Agob Va,E ¶m KQ>Zoer AZwHy$b àmW{‘H$ KQ>Zm§Mr g§»¶m E = n(E),Z‘wZm AdH$memVrb EHy$U àmW{‘H$ KQ>Zm§Mr g§»¶m S=n(S),E ¶m KQ>ZoMr g§ mì¶Vm = P(E),
KQ>ZoMr g§^mì¶Vm =KQ>Zoer AZwHy$b àmW{‘H$ KQ>Zm§Mr g§»¶m
Z‘wZm AdH$memVrb EHy$U àmW{‘H$ KQ>Zm§Mr g§»¶m P(E) =
AnyUmªH$ hm JwUmoÎma ñdê$nmV gwÕm {b{hbm OmVmo. AmnU KQ>ZoÀ¶m g§ mì¶VoMr ì¶m»¶m Imbrbà‘mUoH$ê$ eH$Vmo.
KQ>ZoMr g§ mì¶Vm hr E ¶m KQ>Zoer AZwHy$b Agboë¶m àmW{‘H$ KQ>Zm§Mr g§»¶m Am{U Z‘wZm AdH$memVrbEHy$U àmW{‘H$ KQ>Zm§Mr g§»¶m ¶m§Mo JwUmoÎma Amho.
Xþgè¶m eãXmV, Oa ¶mÑpÀN>H$ Z‘wZm AdH$me‘ܶo 'n' {ZînÎmr Am{U E ¶m KQ>Zobm AZwHy$b 'm'AmhoV, Va E ¶m KQ>ZoMr g§^mì¶VoMr ì¶m»¶m m Mo n er JwUmoÎma ho Amho.
P(E) = m : n =(E)(S)
m nn n
AmVmn¶ªV AmnU MMm© Ho$br Amho H$s, KQ>ZoMr g§ mì¶Vm hr AnyUmªH$s ñdê$nmVrb g§»¶mË‘H$ qH$‘VAmho.
ho gd© KQ>Zm§Zm g˶ Amho H$m? g§ mì¶Vm AnyUmªH$s Zgboë¶m KQ>Zm AmhoV H$m? H$m§hr CXmhaUm§Mm {dMmaH$am.AmnU ’$mgm ’o$H$bm Ago g‘Oy
(i) Z¡g{J©H$ g§»¶m ¶oʶmMr g§ mì¶Vm {H$Vr?
¶oWo, S = {1, 2, 3, 4, 5, 6} n(S) = 6
E = {Z¡g{J©H$ g§»¶m {‘i{dUo}E = {1, 2, 3, 4, 5, 6} n(E) = 6
P(E) =(E)(S)
nn =
66
= 1
(ii) 7 nojm bhmZ g§»¶m {‘i{dʶmMr g§ mì¶Vm {H$Vr?n(S) = 6
E = {7 nojm bhmZ g§»¶m {‘iUo}E = {1, 2, 3, 4, 5, 6} n(E) = 6
P(E) =(E) 6(S) 6
nn = 1
darb XmoZ àg§Jm‘ܶo, Vwåhr nmhmb H$s, E = S Am{U n(E) = n(S) Am{U P(E) = 1, E ¶m KQ>ZoMr
n(E)n(S)
Q>rn … g§^mì¶VoMr emór¶ì¶m»¶m Cn¶moJr nS>Vo. Oa e³¶Agboë¶m {ZînÎmtMr g§»¶m‘¶m©{XV Am{U {ZînÎmr g‘mZ[a˶mg§ dZr¶ AmhoV.
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Probability 103
g§ mì¶Vm 1 nyU© g§»¶m Amho. Aem KQ>Zm§Zm Z³H$s KQ>Zm Ago åhUVmV. Ooìhm Z‘wZm AdH$memVrb gd© KQ>H$KQ>Zoer AZwHw$b AmhoV.
¶mÑpÀN>H$ à¶moJmVrb Z‘wZm AdH$membm Z³H$s qH$dm ImÌrMr KQ>Zm åhUVmV. Oa H$moU˶mhr MmMUrà¶moJm‘ܶo H$moUVmVar EH$ KQ>H$ Z³H$s AmT>iVmo.
Z³H$s KQ>ZoMr g§ mì¶Vm 1 Amho.
{dMma H$am !Ooìhm ZmUo CS>{dbo Va N>mn qOH$Vmo Am{U H$mQ>m Ambr Va haVmo. hr H$moU˶m àH$maMr KQ>Zm Amho?
˶mMr g§ mì¶Vm {H$Vr?(iii) 7 nojm ‘moR>r g§»¶m {‘i{dʶmMr g§ mì¶Vm {H$Vr?
n(S) = 6
A = {7 nojm ‘moR>r g§»¶m}
A = { } = n(A) = 0
P(A) =(A) 0(S) 6
nn = 0
(iv) 1 nojm bhmZ g§»¶m {‘i{dʶmMr g§ mì¶Vm {H$Vr?
n(s) = 6
A = {1 nojm bhmZ g§»¶m}
A = { } n(A) = 0
P(A) =(A) 0(S) 6
nn = 0
darb XmoZ àg§Jm‘ܶo Vwåhr nmhmb H$s,
A = Am{U n(A) = 0, P(A) = 0 i.e., 'A' ¶m KQ>ZoMr g§ mì¶Vm '0' Amho. hr EH$ nyU© g§»¶m Amho.Aem KQ>Zm§Zm Ae³¶ KQ>Zm Ago åhUVmV.
H$moU˶mhr MmMUr à¶moJm‘ܶo Or KQ>Zm H$moU˶mhr pñWVrV KSy>Z ¶oV Zmhr {Vbm Ae³¶ KQ>Zm AgoåhUVmV.
Ae³¶ KQ>ZoMr g§ mì¶Vm '0' AgVo.
darb MM}dê$Z AmnU Agm {ZîH$f© H$mTy> eH$Vmo H$s EImÚm KQ>ZoÀ¶m g§ mì¶Vo{df¶r Imbrb ~m~r ¶oVmV.
* Oa A = , Va n(A) = 0 P(Ae³¶ KQ>Zm) = 0
* Oa A = S, Va n(A) = n(S) P(ImÌrMr KQ>Zm) = 1
* A hr Aer KQ>Zm Amho, Á¶m‘ܶo Ae³¶ KQ>Zm Am{U Z³H$s KQ>Zm gmoSy>Z BVa AmhoV. n(A) > 0 Am{U n(A) < n(S)
P(A) > 0 Am{U P(A) < 1
0 P(A) 1 Ae³¶ KQ>Zogh H$moU˶mhr A KQ>ZogmR>r Am{U Z¸$s KQ>ZogmR>r 0 P(A) 1
EImÚm KQ>ZoMr g§ mì¶Vm hr 0 Am{U 1 ‘Yrb g§»¶m Amho Am{U ˶m‘ܶo 0 Am{U 1 AmhoV, ’$º$ Oa
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104 UNIT-5
˶m‘ܶo AZwH«$‘o Ae³¶ KQ>Zm Am{U ImÌrÀ¶m KQ>Zm AmhoV.AmVm, AmnU KQ>ZoÀ¶m g§ mì¶VoMo ñnï>rH$aU H$ê$.
* Zoh‘r 0 Am{U 1 ¶m XmoZ nyU© g§»¶m§À¶m‘ܶo AgVo.* hm 0 nojm ‘moR>m Am{U 1 noojm bhmZ AnyUmªH$ Amho.* KQ>ZoMr g§ mì¶Vm 0 qH$dm 1 Agy eH$Vo qH$dm 0 Am{U 1 ‘Yrb H$moUVmhr AnyUmªH$ Agy eH$Vmo.
darb ¶w³Ë¶mÀ¶r g§^mì¶Vm Imbrbà‘mUo à‘mUmV Xe©{dVm ¶oVo.0.5
0 ½Impossible Certain
EImÚm KQ>ZoMr g§ mì¶Vm H$mT>ʶmÀ¶m H$m§hr CXmhaUm§Mo ñnï>rH$aU Imbrbà‘mUo {Xbobo Amho. ˶m§MmAä¶mg H$am.
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1 … ’$mgm ’o$H$bm. Imbrb KQ>Zm {‘i{dʶmMr g§ mì¶Vm H$mT>m.(i) 5 hr g§»¶m ¶oʶmMr (ii) {df‘ g§»¶m ¶oʶmMr(iii) 2 nojm ‘moR>r g§»¶m ¶oʶmMr (iv) 6 Mo ‘yi Ad¶d ¶oʶmMr
CH$b … ’$mgm ’o$H$ë¶mda ¶oUmao, Z‘wZm AdH$me S = {1, 2, 3, 4, 5, 6} n(S) = 6
(i) 5 hr g§»¶m ¶oʶmMr 'A' hr KQ>Zm Amho Ago ‘mZy.
A = { 5 } n(A) = 1
P(A) =(A) 1(S) 6
nn
(ii) {df‘ g§»¶m {‘i{dʶmMr 'B' hr KQ>Zm Amho Ago ‘mZy.
B = {1, 3, 5} n(B) = 3
P(B) =(B) 3 1(S) 6 2
nn
(iii) 2 nojm ‘moR>r g§»¶m {‘i{dʶmMr 'C' hr EH$ KQ>Zm Amho Ago ‘mZy.C = {3, 4, 5, 6} n(C) = 4
P(C) =(C) 4 2(S) 6 3
nn
(iv) 6 Mo ‘yi Ad¶d {‘i{dʶmMr 'D' hr KQ>Zm Amho Ago g‘Oy.
D = {2, 3} n(D) = 2
P(D) =(D) 2 1(S) 6 3
nn
CXmhaU 2 … EH$ Mm§Jbo ZmUo XmoZ doim CS>{dbo Va Imbrb KQ>Zm {‘i{dʶmMr g§ mì¶Vm H$mT>m.(i) XmoZ N>mn (ii) H$‘rV-H$‘r EH$ N>mn(iii) N>mn Zgbobr (iv) Zo‘H$m EH$ H$mQ>m
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Probability 105
CH$b … Oa EH$ CÎm‘ ZmUo XmoZ doim da CS>{dbo Va Z‘wZm AdH$me S = {HH, TT, HT, TH} n(S) = 4
(i) A hr XmoZ N>mn {‘i{dʶmMr KQ>Zm ‘mZy.
A = {HH) n(A) = 1 P(A) =(A) 3(S) 4
nn =(C) 1(S) 4
(ii) B hr H$‘rV H$‘r EH$ N>mn {‘i{dʶmMr KQ>Zm ‘mZy.
B = {HH, HT, TH) n(B) = 3
P(B) =(B) 3(S) 4
nn
(iii) C hr KQ>Zm N>mn Z ¶oʶmMr Amho Ago g‘Oy
C = {TT) n(C) = 1
P(C) =(C) 1(S) 4
nn
(vi) D hr Zo‘H$s EH$ H$mQ>m ¶oʶmMr KQ>Zm ‘mZy.
D = { HT, TH) n(D) = 2
P(D) =(D) 2(S) 4
nn
CXmhaU 3 … VrZ CÎm‘ ZmUr EH$mM doir EH${ÌV CS>{dbr Va Imbrb KQ>Zm {‘iʶmMr g§^mì¶Vm H$mT>m.(i) gd© H$mQ>m (ii) H$‘rV H$‘r EH$ H$mQ>m(iii) OmñVrV OmñV EH$ H$mQ>m (iv) OmñVrV OmñV XmoZ N>mn
CH$b … VrZ CÎm‘ ZmUr EH$mM doir EH${ÌV CS>{dbr, Va Z‘wZm AdH$me
S = {HHH, HHT, HTH, THH, HTT, THT, TTH, TTT} n(S) = 8
(i) A hr gd© H$mQ>m {‘i{dʶmMr KQ>Zm Amho.
A = { TTT } n(A) = 1
P(A)=(A) 1(S) 8
nn
(ii) B hr H$‘rV H$‘r EH$ H$mQ>m Agbobr KQ>Zm Amho.
B = {HHT, HTH, THH, HTT, THT, TTH, TTT}
n(B) = 7 P(B) =(B) 7(S) 8
nn
(iii) C hr OmñVrV OmñV EH$ H$mQ>m {‘i{dʶmMr KQ>Zm Amho.
C = {HHH, HHT, HTH, THH}
n(C) = 4 P(C)=(C) 4(S) 8
nn
(iv) OmñVrV OmñV XmoZ N>mn ¶oʶmMr D hr KQ>Zm Amho.
D = {HHT, HHT, HTH, THH, HTT, THT, TTH, TTT}
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106 UNIT-5
n(D) = 7 P(D) =(D) 7(S) 8
nn
CXmhaU 4 … XmoZ {Z…njnmVr ’$mgo EH$XmM {’$a{dbo Va Imbrb KQ>Zm {‘iʶmMr g§^mì¶Vm {H$Vr?
(i) XmoÝhr A§H$ gmaIoM (ii) A§H$mOr ~oarO 7 (iii) A§H$mMr ~oarO 10 nojm H$‘r
CH$b … Amnë¶mbm ‘m{hV Amho H$s, Ooìhm XmoZ {Z…njnmVr ’$mgo EH$XmM {’$a>{dbr, Va e³¶ Agboë¶m EHy$U{ZînÎmtMr g§»¶m 6 × 6 = 36 Amho.
n(S) = 36
(i) A hr XmoÝhr A§H$ gmaIoM Agbobr KQ>Zm ‘mZy.
A= {(1, 1), (2, 2), (3, 3), (4, 4), (5, 5), (6, 6)}
n(A) = 6 P(A) =(A) 6(S) 36
nn
(ii) B hr XmoZ A§H$mMr ~oarO 7 ¶oUmar KQ>Zm ‘mZy.
B= {(1, 6), (2, 5), (3, 4), (4, 3), (5, 2), (6, 1)}
n(B) = 6 P(B) =(B) 6(S) 36
nn
(iii) C hr XmoZ A§H$mMr ~oarO 10 nojm H$‘r AgUmar KQ>Zm ‘mZy.
C = {(1, 6), (1, 5), (1, 4), (1, 3), (1, 2), (1, 1), (1, 2), (2, 2), (2, 3), (2, 4), (2, 5),(2, 6), (3, 1), (3, 2), (3, 3), (3, 4), (3, 5), (3, 6), (4, 1), (4, 2), (4, 3), (4, 4), (4, 5), (5,1), (5, 2), (5, 3), (5, 4), (6, 1), (6, 2), (6, 3)}
n(C) = 30
P(C)=(C) 30(S) 36
nn
CXmhaU 5 … EH$m dJm©‘ܶo 30 ‘wbo Am{U 25 ‘wbr AmhoV. {dÚm϶mªMr {ZdS> ghOnUo Ho$br. {ZdS>boë¶m{dÚm϶mªMr g§ mì¶Vm H$mT>m. (i) ‘wbo (ii) ‘wbr
CH$b … EHy$U {dÚm϶mªMr g§»¶m = 30 + 25 = 55
n(S) = 55(i) A hr ‘wbm§Mr {ZdS> H$aʶmMr KQ>Zm ‘mZy. n(A) = 30
(ii) B hr ‘wbrMr {ZdS> H$aʶmMr KQ>Zm ‘mZy. n(B) = 25
CXmhaU 6 … {ZdS>boë¶m {bn dfm©‘ܶo 53 a{ddma AmhoV Va ˶mMr g§^mì¶Vm {H$Vr?CH$b … {bn dfm©‘ܶo Agbobo {Xdg = 366 {Xdg
366 {Xdg = 52 AmR>dS>o Am{U 2 {Xdgam{hbobo XmoZ {Xdg ho(i) a{ddma Am{U gmo‘dma (ii)gmo‘dma Am{U ‘§Jidma
(iii) ‘§Jidma Am{U ~wYdma (iv) ~wYdma Am{U Jwédma(v) Jwédma Am{U ewH«$dma (vi) ewH«$dma Am{U e{Zdma
(vii) e{Zdma Am{U a{ddma53 a{ddma Agboë¶m {bn dfm©‘ܶo eodQ>Mo XmoZ {Xdg a{ddma Am{U gmo‘dma qH$dm e{Zdma Am{U a{ddma¶mn¡H$s EH$ AmhoV.
P(A) =(A) 30(S) 55
nn
P(B) =(B) 25(S) 55
nn
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Probability 107
Aem AZwHy$b {ZînÎmtMr g§»¶m = n(A) = 2
Z‘wZm AdH$mem‘ܶo EHy$U e³¶ Agboë¶m {ZînÎmtMr g§»¶m = n(S) = 7
P(A) =(A)(S)
nn P(53 a{ddma Agbobo {bn df©)=
27
CXmhaU 7 … EH$m {nedr‘ܶo 6 bmb M|Sy> Am{U H$mhr {Zio M|Sy> AmhoV. {Zim M|Sy> H$mT>ʶmMr g§ mì¶Vm hr bmbM|Sy> H$mT>ʶmÀ¶m g§ mì¶VoÀ¶m XþßnQ> Amho. Va {nedrVrb {Zù¶m M|Sy>Mr g§»¶m H$mT>m.
CH$b … {Zù¶m M|Sy>Mr g§»¶m = x ‘mZy.EHy$U M|Sy>Mr g§»¶m = (6 + x)
P(bmb M|Sy> H$mT>ʶmMr g§ mì¶Vm) =6
6 x
P({Zim M|Sy> H$mT>ʶmMr g§^mì¶Vm)= 6x
x 6x
x = 626 x 6
xx =
126 x
12(6 + x) = x(6 +x) 72 + 12x = 6x + x2
x2 – 6x – 72 = 0 (x – 12)(x + 6) = 0 x – 12 = 0 or x + 6 = 0 x = 12 or x = – 6
{Zù¶m M|Sy>Mr g§»¶m = 12
CXmhaU 8 … CÎm‘ {ngboë¶m 52 nζm§À¶m gQ>mVyZ EH$ nÎmm ghOnUo H$mT>bm Va Imbrb KQ>Zm§Mr g§^mì¶VmH$mT>m.(i) amUr (ii) bmb amOm (iii) Mm¡H$Q> (iv) ~Xm‘Mm¡H$Q> ~Xm‘ BpñnH$ {H$bmda
A A A A
CH$b … {H$bmda Am{U BpñnH$Mo nÎmo H$mù¶m a§JmMo AmhoV. ~Xm‘ Am{U Mm¡H$Q>Mo nÎmo bmb AmhoV. à˶oH$ g§MmMo 13 nÎmoAmhoV. ˶m‘ܶo 3 à{Vð>rV qH$dm Xe©Zr n¥ð> mJmMo nÎmo AmhoV. Vo åhUOo amOo (K), amʶm (Q) Am{U Jwbm‘ (J)
CÎm‘ {ngboë¶m nζm§À¶m gQ>mVyZ g‘mZar˶m g§ dZr¶ {ZînÎmr {‘iVrb. 52 Ioim§À¶m nζm§Mo Imbrbà‘mUo dJuH$aU Ho$bo Amho.
BpñnH$ A 2 3 4 5 6 7 8 9 10 J Q K 13
~Xm‘ A 2 3 4 5 6 7 8 9 10 J Q K 13
{H$bmda A 2 3 4 5 6 7 8 9 10 J Q K 13
Mm¡H$Q> A 2 3 4 5 6 7 8 9 10 J Q K 13
CÎm‘ {ngboë¶m 52 nζm§n¡H$s EH$ nÎmm 52C1 àH$mao {ZdS>Vm ¶oVmo. n(S) = 52
(i) ¶oʶmMr g§^mì¶Vm n(Q) = 4
P(Q) =(Q) 4(S) 52
nn
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108 UNIT-5
(ii) bmb amOm ¶oʶmMr g§^mì¶Vm n(RK) = 2
P(RK) =2
52(S)nn(RK)
(iii) Mm¡H$Q> ¶oʶmMr g§^mì¶Vm n(D) = 13
P(D) =1852(S)n
n(D)
(iv) ~Xm‘ ¶oʶmMr g§^mì¶Vm n(H) = 13
P(H) =1352(S)n
n(H)
CXmhaU 9 … XmoZ ghO KS>Umao à¶moJ {dMmamV ¿¶m.
(i) CÎm‘ ZmUo EH$Xm CS>{dbo. (ii) CÎm‘ ’$mgm EH$Xm ’o$H$bm.
à˶oH$ àg§JmVrb à˶oH$ àmW{‘H$ KQ>ZoMr g§ mì¶Vm H$mT>m Am{U ~oarO H$am. ˶mdê$Z Vwåhr H$moUVm
{ZîH$f© H$mTy> eH$Vm?
CH$b … (i) EH$ ZmUo CS>{dUo
S = {H, T} n(S) = 2
˶mÀ¶m àmW{‘H$ KQ>Zm,
E1 = { H } E2 = { T } P(E1) =12 P(E2) =
12
P(E1) Am{U P(E2) Mr ~oarO Ho$br AgVm.
P(E1) + P(E2) =1 12 2
= 1
(ii) ’$mgm ’o$H$Uo
S = {1, 2, 3, 4, 5, 6} n(S) = 6
˶mÀ¶m àmW{‘H$ KQ>Zm,
E1 = { 1 }, E2 = { 2 }, E3 = { 3 }, E4 = { 4 }, E5 = { 5 }, E6 = { 6 }
P(E1) = P(E2) = P(E3) = P(E4) = P(E5) = P(E6) =16
darb gd© àmW{‘H$ KQ>Zm§Mr ~oarO Ho$br AgVm Amnë¶mbm {‘iob.
P(E1) + P(E2) + P(E3) + P(E4) + P(E5) + P(E6)
=1 1 1 1 16 6 6 6 6 =
66 = 1
darb CXmhaUm‘ܶo AmnU nmhVmo H$s, à¶moJmVrb gd© àmW{‘H$ KQ>Zm§À¶m g§ mì¶VoMr ~oarO 1 Amho. gd©
gmYmaUnUo ho gdmªgmR>r g˶ Amho.
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Probability 109
ñdmܶm¶ 5.1
1. EH$ ’$mgm CS>{dbm. Va Imbrb KQ>Zm {‘i{dʶmMr g§ mì¶Vm H$mT>m.
(i) 4 hr g§»¶m (ii) dJ© g§»¶m
(iii) KZ g§»¶m (iv) 1 nojm ‘moR>r g§»¶m
2. XmoZ ZmUr EH${ÌV da CS>{dbr. Va Imbrb KQ>Zm {‘i{dʶmMr g§ mì¶Vm H$mT>m.
(i) H$mQ>m Zmhr (ii) OmñVrV OmñV XmoZ H$mQ>m
(iii) Z³H$s EH$ N>mn (iv) H$‘rV H$‘r EH$ H$mQ>m
3. VrZ ZmUr EH${ÌVnUo da CS>{dbr Va Imbrb KQ>Zm {‘i{dʶmMr g§ mì¶Vm H$mT>m.
(i) H$‘rV H$‘r EH$ N>mn (ii) OmñVrV OmñV XmoZ N>mn
(iii) N>mn Zmhr (iv) gd© N>mn
4. XmoZ ’$mgo EH${ÌVnUo da CS>{dbo Va Imbrb KQ>Zm {‘i{dʶmMr g§ mì¶Vm H$mT>m.
(i) A§H$mMr ~oarO 8 (ii) g§»¶m§Mr ~oarO 12 nojm H$‘r
(iii) ~oaOobm 4 Zo ^mJ OmVmo (iv) JwUmH$ma 12
(v) JwUmH$ma 20 nojm H$‘r (vi) JwUmH$mambm 5 Zo ^mJ OmVmo.
5. 1 nmgyZ 50 n¶ªVÀ¶m g§»¶oMr {ZdS> ghOnUo Ho$br. Va ˶m§Mr g§ mì¶Vm {H$Vr?
(i) ‘yi g§»¶m (ii) nyU© KZ Zmhr
(iii)nyU© dJ© Amho (iv) {ÌH$moUmH¥$Vr g§»¶m Amho
(v) 6 ˦m nQ>rVrb (vi) 2 ˦m nQ>rVrb Zmhr.
6. 52 nÎmo {ngyZ 1 nÎmm ghOnUo CMbbm. da Imbrbn¡H$s EH$ nÎmm CMbʶmMr g§ mì¶Vm H$mT>m.
(i) bmb a§JmMm nÎmm (ii) H$mù¶m a§JmVm nÎmm Zmhr
(iii) E³H$m Zmhr (iv) Mm¡H$Q> Zmhr
(v)H$mim amOm (vi) 10 nojm H$‘r g§»¶m Agbobm ~Xm‘
7. 2, 5, 7 ho A§H$ nwÝhm-nwÝhm Z KoVm ¶m g§»¶mnmgyZ 2 A§H$s g§»¶m ~ZVmV. Imbrb g§»¶m ~ZVmV Va
˶m§Mr g§ mì¶Vm H$mT>m.
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110 UNIT-5
(i) dJ© g§»¶m (ii) 3 Zo ^mJ OmUmè¶m
(iii)52 nojm ‘moR>r (iv) 57 nojm bhmZ
(v) 25 nojm bhmZ (vi) nyU© g§»¶m
8. 30 CÎm‘ Am§ã¶m‘ܶo 9 Hw$Obobo Am§~o {‘gibo. ghOnUo EH$ Am§~m {ZdS>bm. Va
(i) CÎm‘ Am§~m (ii) Hw$Obobm Am§~m ho {ZdS>ʶmMr g§ mì¶Vm {H$Vr?
9. hmoirÀ¶m gUmbm gmoZmbrZo bmb, {Zim, {hadm, Jwbm~r, {ndim, Om§ im Am{U Zma§Jr a§J dmnê$Z 7 ~mQ>ë¶m a§JrV
nmʶmZo ^aë¶m. EH$ ~mQ>br ghOnUo {ZdS>br. Imbrb a§JmMr ~mQ>br {ZdS>ʶmMr g§ mì¶Vm {H$Vr?
(i) Zma§Jr a§J (ii) {ndim a§J Zmhr
(iii) ZmernwS>r a§J (VnH$sar a§J) (iv) bmb qH$dm {hadm ¶mn¡H$s EH$
(v) {ndim qH$dm Jwbm~r Zmhr
10. EH$m noQ>rV 144 noZ AmhoV ˶mn¡H$s 20 Iam~ Am{U am{hbobo CÎm‘ AmhoV. Oa EH$m 춺$sZo Mm§Jbo noZ
IaoXr Ho$bo nU Iam~ IaoXr Ho$bo ZmhrV. XþH$mZXmamZo noQ>rVyZ ghOnUo EH$ noZ H$mTy>Z ˶m 춺$sbm {Xbo.
Va Vmo 춺$s
(i) Vo IaoXr H$aVmo (ii) Vo IaoXr H$aV Zmhr ¶mMr g§ mì¶Vm {H$Vr?
KQ>Zm (Events)
AmVmn¶ªV AmnU KQ>Zm {df¶r Aä¶mg Ho$bobm Amho. KQ>Zmda AmYmarV ˶m§Mo dJuH$aU doJdoJù¶màH$mamV Ho$bo OmVo.
KQ>Zm
Z³H$s KQ>Zm gmܶm KQ>Zm g§¶wº$ KQ>ZmAm{U qH$dm
Ae³¶ KQ>Zm àmW{‘H$ KQ>Zm
AmVm AmnU AmUIr H$m§hr KQ>Zm§Mm Aä¶mg H$ê$¶m Á¶m gmܶm qH$dm g§¶w³V KQ>Zm AmhoV.
H$moQ>r KQ>Zm (Complementary events)
AmnU ’$mgm EH$Xm ’o$H$bm Ago g‘Oy. ˶mÀ¶m XmoZ KQ>Zm§Mm {dMma H$am.
(i) g‘ g§»¶m {‘i{dUo - E1 E1 = {2, 4, 6}
(ii) {df‘ g§»¶m {‘i{dUo - E2 E2 = {1, 3, 5}
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Probability 111
AmVm AmUIr EH$ ""g‘ g§»¶m Z {‘iUo'' hr KQ>Zm ¿¶m. = {1, 3, 5}
XmoZ KQ>Zm§Mr VwbZm H$am.
""{df‘ g§»¶m {‘i{dUo'' Am{U ""g‘ g§»¶m Z {‘iUo''
˶m XmoÝhr g‘mZ AgyZ ~amo~a {1, 3, 5} Amho.
E2 hr E Zmhrer g‘mZ Amho, AmnU nmhVmo H$s E1 hr KQ>Zm KS>Vo ’$º$ Ooìhm E2 hr KS>V Zmhr Am{UCbQ>njr
E1 Am{U E2 ¶m KQ>Zm§Zm H$moQ>r KQ>Zm Ago åhUVmV.
åhUOoM "KQ>Zm E' hr Zgbobr "KQ>Zm E' er H$moQ>r Am{U "Zgbobr KQ>Zm E' hr "KQ>Zm E'Mr H$moQ>rAmho.E KQ>ZoMr H$moQ>r E Zo Xe©{dVmV.
E KQ>ZoÀ¶m H$moQ>rbm "E Zgbobr KQ>Zm' gwÕm åhUVmV. KQ>ZoÀ¶m H$moQ>rbm "KQ>ZoMm ZH$ma' Ago gwÕm åhUVmV.
AmVm, AmnU KQ>Zm E Am{U {VMr H$moQ>r KQ>Zm E ¶m‘Yrb g§~§Y H$mTy>.
Imbrb H$moï>H$ Aä¶mgm. H$m§hr KQ>Zm, ˶mÀ¶m H$moQ>r KQ>Zm Am{U ˶m§Mr g§ mì¶Vm {Xbobr Amho.
P(E) Am{U P(E ) {df¶r AmnU H$moUVm {ZîH$f© H$mTy> eH$Vmo?
ghO KS>Umao KQ>Zm E H$moQ>r KQ>Zm qH$dm P(E) P(E ) P(E) + P(E ) à¶moJ Zgbobr KQ>Zm E
ZmUo CS>{dUo N>mn {‘i{dUo H$mQ>m {‘i{dUo
S {H, T} qH$dm
n(S) = 2 E = {H} N>mn Z {‘i{dUo12
12
12 +
12 = 1
E = {T}
2) ’$mgm ’o$H$Uo 3 nojm ‘moR>r 3 nojm ‘moR>r Zgbobr
g§»¶m {‘i{dUo g§»¶m {‘i{dUo36
36
36
+36
= 1
S = {1,2,3,4,5,6} E = {4, 5, 6} E = {1, 2, 3}n(S) = 6
VrZ˦m nQ>rVrb VrZ˦m nQ>rV
g§»¶m {‘i{dUo Zgbobr g§»¶m {‘i{dUo26
46
26 +
46 = 1
E = {3, 6} E = {1, 2, 4, 5}
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112 UNIT-5
darb H$moï>H$mdê$Z, Amåhr Agm {ZîH$f© H$mTy> H$s,P(E) + P(E ) = 1 P(E ) = 1 – P(E)
Xþgè¶m eãXmV, P(E) + P(E Zmhr) = 1P(E Zmhr) = 1 – P(E) P(E) = 1 – P(E Zmhr)
AmnU gQ>m§Mr ^mfm dmnê$Z gwÕm darb g§~§Y {gÕ H$ê$ eH$Vmo.Amåhmbm ‘m{hV Amho, E E = S Am{U E E =
n(E) + n(E ) = n(S)n(S) Zo gdm©Zm ^mJbo.
(E)(S)
nn +
(E)(S)
nn =
(S)(S)
nn P(E) + P( E ) = 1 P(E) = 1 – P( E )
Q>rn … Oa A hr KQ>Zm 'm' doim KS>Vo Am{U 'n' doim KS>V Zmhr, ¶m gd© g‘mZ[a˶m g§ dZr¶ KS>VmV Va
* KQ>Zm KS>ʶmMr g§ mì¶Vm = mm n
* KQ>Zm Z KS>ʶmMr g§ mì¶Vm =n
m n
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1 … Oa gm‘Zm qOH$ʶmMr g§^mì¶Vm 0.3 Amho. Va gm‘Zm J‘{dʶmMr g§ mì¶Vm {H$Vr?CH$b … A hr gm‘Zm qOH$ʶmMr KQ>Zm Amho. Va A hr gm‘Zm haʶmMr KQ>Zm Amho.
{Xbobo. P(A) = 0.3.Amåhmbm ‘m{hV Amho H$s, P(A) + P( A ) = 1
P( A ) = 1 - P(A) P( A ) = 1 - 0.3 = 0.7gm‘Zm J‘{dʶmMr g§ mì¶Vm 0.7.
CXmhaU 2 … Oa A hr ¶mÑpÀN>H$ à¶moJmMr KQ>Zm Aem[aVrZo Amho H$s,
P(A) : P (A ) = 5:11, Va (i) P(A) Am{U P (A ) H$mT>m (ii) P(A) + P(A ) = 1 ho VnmgyZ nmhm.
CH$b … (i) {Xbobo P(A) : P( A ) = 5:11P(A)P(A)
511 11 P(A = 5 P( A )
11 P(A) = 5 [1-P( A )] ( P(A) + P( A ) = 1)
11 P(A) = 5 – 5 P( A ) 11 P(A) + 5 P(A)=5 6 P(A = 5
P(A) =5
16P( A ) = 1 – P(A)
P( A ) = 1 –5
16P( A ) =
1116
{dMma H$am …
H$moU˶mhr ghO KS>Umè¶mà¶moJm‘ܶo Z³H$s KQ>ZoMrH$moQ>r hr Ae³¶ KQ>Zm AmhoH$m? ¶m KQ>ZmgmR>r darbMMm© Ho$bobm g§~§Y bmJy nS>VmoH$m? JQ> H$ê$Z MMm© H$am.
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Probability 113
(ii) P(A) + P( A ) = 1
S>mdr ~mOy (LHS) = P(A) + P( A )
=5
16 +1116 =
1616 = 1 = COdr ~mOy (RHS)
nañna§mer Ho$di KQ>Zm (Mutually exclusive events)’$mgm ’o$H$ʶmÀ¶m ghO KS>Umè¶m à¶moJmMm {dMma H$ê$¶m. S = {1, 2, 3, 4, 5, 6}Aem KQ>Zm ‘mZy,
E1 = 3 nojm bhmZ {‘iUmar g§»¶m E1 = {1, 2}E2 = 2 nojm ‘moR>r {‘iUmar g§»¶m E2 = {5, 6}E1 Am{U E2 ¶m H$moQ>r KQ>Zm ZmhrV. E1 E2 S
Va ¶m KQ>Zm H$moU˶m àH$maÀ¶m AmhoV?bj Úm H$s E1 Am{U E2 ¶m EH${ÌV qH$dm EH$mMdoir KS>V ZmhrV. Ooìhm E2 hr KS>V Zgob Va ’$º$
E1 KS>Vo Am{U CbQ>njr.Voìhm AmnU E1 Am{U E2 ¶m KQ>Zm nañnamer Ho$di AmhoV Ago åhUy. åhUOoM EH$ KQ>Zm KS>V Agob
Va Xþgè¶m KQ>ZoÀ¶m KS>ʶmg ZmH$maVo.XmoZ qH$dm A{YH$ KQ>Zm nañnamer Ho$di AgVmV. Oa EH$ KQ>Zm KS>V Agob Va Xþgar KQ>Zm KS>ʶmgWm§~[dVmV qH$dm ZmH$maVmV.
Oa E1 Am{U E2 ¶m nañnamer Ho$di KQ>Zm AmhoV Va, E1 E2 = .
gQ> {gÕm§VmÀ¶m ^mfo‘ܶo E1 Am{U E2 ho Ag§~§YrV gQ> AmhoV.˶mZm gm‘mB©H$ {ZînÎmr qH$dm àmW{‘H$ KQ>Zm ZmhrV. n(E1 E2) = n(E1) + n(E2)
XmoÝhr ~mOybm n(S) Zo ^mJ {Xë¶mgAmåhmbm {‘iob.
1 2(E E )(S)
nn = 21 (E )(E )
(S) (S)nn
n n P(E1 E2) = P(E1) + P(E2)
¶m {ZH$mbmbm g§^mì¶VoÀ¶m ~oaOoMm {Z¶‘ åhUVmV.
bjmV R>odm …
• XmoZ nañnam§er Ho$di KQ>Zm§Mr g§ mì¶Vm H$mT>ʶmgmR>r hm {Z¶‘ dmnaVmV.• XmoZ nojm OmñV nañnamer Ho$di KQ>Zm§gmR>rgwÕm hm {Z¶‘ dmT>{dbm OmD$ eH$Vmo.
If E1, E2, E3 ...............En ¶m nañnamer Ho$di KQ>Zm AmhoV Va,P(E1 E2 E3 ...........En) = P(E1) + P(E2) + P(E3) ...........P(En)
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1 … XmoZ ZmUr EH$mMdoir CS>{dbr Va Z³H$s XmoZ N>mn qH$dm H$‘rV H$‘r EH$ H$mhm da ¶oʶmMrg§^mì¶Vm H$mT>m.
CH$b … S ={HH, HT, TH, TT} n(S) = 4
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114 UNIT-5
10 nojm OmñV ~oarO qH$dm 5 nojm H$‘r ~oarO ¶oʶmMr g§^mì¶Vm9
36 qH$dm14
CXmhaU 3 … CÎm‘[a˶m {ngboë¶m 52 IoimÀ¶m nζm§À¶m gQ>mVyZ ghOnUo nÎmo H$mTbo. Va bmb nÎmm qH$dmH$mim amOm qH$dm g‘ g§»¶oMm {H$bmda nÎmm ¶oʶmMr g§^mì¶Vm {H$Vr Vo H$mT>m?CH$b … A hr bmb nÎmm {‘iʶmMr KQ>Zm Amho Ago ‘mZy.
n(A) = 13 Mm¡H$Q> + 13 ~Xm‘ n(A) = 26B hr KQ>Zm H$mim amOm {‘iʶmMr Amho Ago ‘mZy.n(B) = 1 (BpñnH$ amOm) + 1 ({H$bmda amOm) n(B) = 2C hr KQ>Zm {H$bmdaMr g‘ g§»¶m Amho Ago ‘mZy
C = (2, 4, 6, 8, 10 ho {H$bmdaMm nÎmo) n(C) = 5
A ¶m KQ>Zo‘ܶo Z³H$s XmoZ N>mn {‘iVmV Ago ‘mZy.
A = {HH} Am{U n(A) = 1 P(A) =(A) 1(S) 4
nn
B ¶m KQ>Zo‘ܶo H$‘rV H$‘r EH$ H$mQ>m {‘iVo Ago ‘mZy.
B = {HT, TH, TT} Am{U n(B) = 3 P(B) =(B) 3(S) 4
nn
AmVm A Am{U B ¶m KQ>Zm nañnamer Ho$di AmhoV. P(A B) = P(A) + P(B) ( g§^mì¶VoMm ~oaOoMm {Z¶‘)
P(A B) =14
+34
=1
Z³H$s XmoZ N>mn qH$dm H$‘rV H$‘r EH$ H$mQ>m {‘i{dʶmMr g§^mì¶Vm 1 Amho.
CXmhaU 2 … EH${ÌVnUo XmoZ ’$mgo ’o$H$bo. Va ~oarO 10 nojm OmñV qH$dm ~oarO 5 nojm H$‘r ¶oʶmMrg§^mì¶Vm {H$Vr?
CH$b … Amåhmbm ‘m{hV Amho H$s, Ooìhm XmoZ ZmUr ’o$H$br Jobr Voìhm n(S) = 36.A hr KQ>Zm 10 nojm OmñV ~oarO ¶oUmar Amho Ago ‘mZy.Va A = {(5,6), (6,5), (6,6)}
n(A) = 3
P(A) =3
36(S)nn(A)
B hr KQ>Zm 5 nojm H$‘r ~oarO ¶oUmar Amho Ago ‘mZy.
B = {(1,1), (1,2), (1,3), (2,1), (2,2), (3,1)} n(B)=6
P(B) =(B)(S)
nn =
636
AmVm, A Am{U B ¶m KQ>Zm nañnamer Ho$di AmhoV. P(A B) = P(A) + P(B) ( g§^mì¶VoMm ~oaOoMm {Z¶‘)
P(A B) =7 636 36 P(A B) =
936 =
14
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Probability 115
P(A) =2652
P(B) =252 P(C) =
552
AmVm A, B Am{U C ¶m nañnamer Ho$di KQ>Zm AmhoV.
P(A B C) = P(A) + P(B) + P(C)
P(A B C) =2652
+252
+552
P(A B C) =26 2 5
52 =3352
bmb nÎmm qH$dm H$mim amOm qH$dm {H$bmdaMo g‘ g§»¶m§Mo nÎmo {‘iʶmMr g§ mì¶Vm3352
CXmhaU 4 … MATHEMATICIAN ¶m eãXmVrb Ajao ghOnUo {ZdS>br Va M qH$dm A Aja {ZdS>ʶmMrg§^mì¶Vm H$mT>m.
CH$b … MATHEMATICIAN ¶m eãXm‘ܶo 13 Ajao AmhoV.n(S) = 13E hr KQ>Zm M ho Aja {‘i{dʶmMr Amho.
n(E) = 2
P(E) =(E)(S)
nn =
213
F hr KQ>Zm A ho Aja ¶oʶmMr Amho. n(F) = 3
P(F) =(F)(S)
nn =
313
AmVm E Am{U F ¶m nañnamer Ho$di KQ>Zm AmhoV.P(E F) = P(E) + P(F)
P(E F) =2
13 +3
13 =5
13CXmhaU 5 … dJm©Vrb 40% {dÚmWu EH$mo (Eco) g§KmMo gXñ¶ AmhoV Am{U 25% {dÚmWu J{UV g§KmMogXñ¶ AmhoV Am{U VoWo EH$mM g§KmMo gXñ¶ Agy eH$VmV. dJm©Vrb {dÚm϶mªMr {ZdS> ghOnUo Ho$bobrAmho. H$moU˶mhr g§KmMo gXñ¶ Zgboë¶m {dÚm϶mªMr g§^mì¶Vm {H$Vr?
CH$b … A hr KQ>Zm EH$mo n(s) =100 ‘mZy (Eco) g§KmVrb gXñ¶m§À¶m {ZdS>rMr Amho Ago ‘mZy.
P(A) =40
100 =
25
B hr KQ>Zm J{UV g§KmVrb gXñ¶m§À¶m {ZdS>rMr Amho Ago ‘mZy. P(B) =25
100 =
14
A Am{U B ¶m nañnamer Ho$di KQ>Zm AmhoV.P(A B) = P(A) + P(B)
P(A B) =25
+14
=1320
EH$mo (Eco) g§K qH$dm J{UV g§KmVrb {dÚmWu gXñ¶m§Mr {ZdS> H$aʶmMr g§ mì¶Vm1320
Amho.AmVm, C hr KQ>Zm H$moU˶mhr g§KmMo gXñ¶ Zgboë¶m {dÚm϶mªMr {ZdS> H$aʶmMr Amho Vr (A B) Mr
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116 UNIT-5
H$moQ>r KQ>Zm Amho.P(A B) + P(C) = 1 P(C) = 1 - P(A B)
P(C) = 1 –1320 =
720 = 35%
H$moU˶mhr g§KmMo gXñ¶ Zgboë¶m {dÚm϶mªMr {ZdS> H$aʶmMr g§^mì¶Vm720 qH$dm 35% Amho.
CXmhaU 6 …¶mÑ[ÀN>H$ à¶moJm‘ܶo A, B Am{U C n¡H$s ’$º$ VrZ OmoS>çm nañnamer Ho$di KQ>Zm AmhoV. OaP(A) = 3
2, P(B) Am{U P(C) =
12 P(A), Va P(B) H$mT>m.
CH$b … P(B) = a ‘mZy
AmVm P(A) = 32
P(B) = 32
a P(C) =12 P(A) =
12 × 1
2 a =34 a
A, B Am{U C ¶m nañnamer Ho$di KQ>Zm AmhoV Ago {Xbobo Amho.
P(A B C) = P(A) + P(B) + P(C)
Á¶mAWu Amåhmbm {‘iVo
P(S) = 1 P(A) + P(B) + P(C) =132
a + a +34
a = 1 46a + 4a + 3a = 1
= 1 13a = 4 a =4
13 P(B) =
413
ñdmܶm¶ 5.2
1. EH$m {d{eð> {Xder 0.64 BVH$m nmD$g nS>ʶmMr g§ mì¶Vm Amho. ˶m {Xder nmD$g Z nS>ʶmMrg§ mì¶Vm {H$Vr?
2. Z‘wݶm‘YyZ Iam~ Zgboë¶m dñVy CMbʶmMr g§ mì¶Vm 7/12 Amho. Va Iam~ dñVy CMbʶmMr g§ mì¶Vm {H$Vr.
3. A hr ghO KS>Umè¶m à¶moJmMr g§ mì¶Vm Aem[aVrZo Amho H$sP(A) : P( A ) = 6:15, Va i) P(A) ii) P( A ) H$mT>m.
4. Oa A Am{U B ¶m nañnamer Ho$di KQ>Zm Aem[aVrZo Amho H$s P(A) =35
Am{U P(B) =27
, Va P(AUB) H$mT>m.5. XmoZ ZmUr EH$X‘ ’o$H$br. Va EH$Va XmoÝhr amOm (N>mnm) qH$dm XmoÝhr amUr (H$mQ>m) ¶oʶmMr g§ mì¶Vm {H$Vr?6. Ooìhm ’$mgm ’o$H$bm OmVmo, Voìhm EH$Va {df‘ g§»¶m qH$dm MmaÀ¶m nQ>rVrb g§»¶m ¶mn¡H$s EH$ ¶oʶmMr
g§ mì¶Vm H$mT>m.7. 1 Vo 25 n¶ªVÀ¶m g§»¶m§À¶m H$mS>m©‘YyZ EH$ g§»¶m H$mS>© ghOnUo {ZdS>bo. Va ˶mbm 3 qH$dm 11 Zo ^mJ
OmUmè¶m g§»¶oMr g§ mì¶Vm H$mT>m.8. EH$X‘ XmoZ ’$mgo ’o$H$bo. Va n¥ð>^mJmdarb g§»¶m§À¶m ~oaOobm 4 qH$dm 5 ¶mn¡H$s EH$mZohr ^mJ Z OmʶmMr
g§ mì¶Vm H$mT>m.H«$‘doe Am{U g§doemÀ¶m JUZooMr g§ mì¶Voer g§~§YrV CXmhaUo …
Amåhmbr ‘m{hV Amho H$s, KQ>ZoMr g§ mì¶Vm Imbrb VrZ ‘w»¶ nm¶è¶m§‘YyZ emoYbr OmVo.(i) n (S) H$mT>Uo (ii) n (A) H$mT>Uo
(iii) P(A) =(A)
(S)
n
n gyÌ dmnê$Z P(A) H$mT>Uo
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Probability 117
¶m KQ>H$mV AmVmn¶ªV Ho$boë¶m ñnï>rH$aUmË‘H$ MM}dê$Z AmnU àmW{‘H$ KQ>Zm§Mr ¶mXr H$ê$Z, d¥jmH¥$VraMyZ qH$dm H$moï>H$mdê$Z n(A) Am{U n(S) AmnU H$mT>bo Amho. Imbrb CXmhaUo Aä¶mgm
na§Vw ¶oWo H$mhr CXmhaUo AmhoV, Á¶m‘ܶo Amnë¶mOdi à˶jnUo H«$‘doe Am{U JUZm H$ê$Z n(A) Am{U n(S)
{‘iVo Imbrb CXmhaUm§Mm Aä¶mg H$am
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1 … 1 Vo 25 g§»¶m Agbobo nÎmo AmhoV. EH$mZ§Va EH$ ¶mà‘mUo XmoZ nÎmo H$mT>bo. Va EH$m â˶mdarb darb g§»¶mhr7À¶m nQ>rVrb Am{U Xþgè¶m nζmdarb g§»¶m 11À¶m nQ>rVrb ¶oʶmMr g§ mì¶Vm {H$Vr?
CH$b … 7À¶m nQ>rVrb nÎmo {7, 14, 21} Am{U 11À¶m nQ>rVrb g§»¶m§Mo nÎmo {11, 22} ho AmhoV.
n(s) = 25C2 n(A)=3C12C1
g§ mì¶Vm = 1 1
2
2C C
C
3
25= 3 2
300=
150
7 À¶m nQ>rVrb Am{U 11 À¶m nQ>rVrb g§»¶m Agbobo XmoZ nÎmo H$mT>ʶmMr g§ mì¶Vm150
Amho.
CXmhaU 2 … 52 nζm§À¶m gQ>m‘YyZ CÎm‘[a˶m {ngyZ ghOnUo Mma nÎmo CMbbo Va
i) gd© Mm¡H$Q> nÎmo ¶oʶmMr g§^mì¶Vm H$mT>m.
ii) XmoZ nÎmo ~Xm‘ Am{U XmoZ nÎmo BpñnH$Mo ¶oʶmMr g§ mì¶Vm H$mT>m.
CH$b … (i) n(A) = 13C4 n(S) = 52C4
P(A) = 4
225
13CC
=13 12 11 1052 51 50 49 =
114165 P(A) =
26820825
(i) n(B) = 13C2 13C2 n(S) = 52C4
P(B) =4
52C2
13C 213C
=
13 12 13 122
4 3 2 15 51 50 49 =
46820825
XmoZ ~Xm‘ Am{U XmoZ BpñnH$Mo nÎmo ¶oʶmMr g§ mì¶Vm268
20825Amho.
CXmhaU 3 … EH$m noQ>r‘ܶo 4 bmb Am{U 3 H$mù¶m JmoQ>çm AmhoV. ghOnUo 4 JmoQ>çm CMbë¶m Va ImbrbKQ>Zm§Mr g§^mì¶Vm H$mT>m.
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118 UNIT-5
(a) A = XmoZ JmoQ>çm bmb AmhoV. (b) B = gd© JmoQ>çm bmb AmhoV.
(c) C = gd© JmoQ>çm H$mù¶m AmhoV.
CH$b … EHy$U 7 JmoQ>çm AmhoV, ˶mn¡H$s 4 JmoQ>çm CMbʶmMo àH$ma7C4 = 35 àH$mao n(S) = 35
(a) 4 bmb JmoQ>çm‘YyZ 2 bmb JmoQ>çm CMbʶmMo àH$ma 4C2 = 6 àH$mao
am{hboë¶m XmoZ JmoQ>çm H$mù¶m AmhoV, ˶m CMbʶmMo àH$ma 3C2 = 3 àH$mao
n(A) = 4C23C2 = 6 3 = 18 àH$mao P(A) =
(A)(S)
nn =
1835
(b) 4 bmb JmoQ>çmnmgyZ 4 bmb JmoQ>çm CMbʶmMo àH$ma 4C4 = 1 àH$mao n(B) = 1 P(B) =135
(c) C hr Ae³¶ KQ>Zm Amho.
3 H$mù¶m JmoQ>çmnmgyZ 4 H$mù¶m JmoQ>çm CMbʶmMo àH$ma e³¶ ZmhrV. P(C) = 0
CXmhaU 4 … EH$m noQ>rV 6 bmb, 7 nm§T>aoo Am{U 7 H$mio M|Sy> AmhoV. XmoZ M|Sy> ghOnUo CMbbo. gd© bmbqH$dm gd© H$mio M|Sy> ¶oʶmMr g§^mì¶Vm {H$Vr?
CH$b … 20 M|Sy>‘YyZ 2 M|Sy> CMbʶmMo àH$ma 20C2 =20 191 2
= 190 àH$mao n(S) = 190
6 bmb M|Sy>‘YyZ 2 bmb M|Sy> CMbʶmMo àH$ma 6C2 = 15 àH$mao
n(A) = 15 P(2 bmb) =15190
7 H$mù¶m M|Sy>‘YyZ 2 H$mio M|Sy> CMbʶmMo àH$ma 7C2 = 21 àH$mao
n(B) = 21 P(H$mio) =21
190
darb XmoZ KQ>Zm ¶m nañnamer Ho$di AmhoV.
P(bmb qH$dm H$mio) =15190
+21
190 =
36190
=15190
XmoZ M|Sy> H$mio qH$dm {Zio ¶oʶmMr g§ mì¶Vm =1895 .
CXmhaU 5… ^maV, Zonmi, nm{H$ñVmZ, lrb§H$m ^yVmZ Am{U ¶m§Zr ìhm°br~m°b ñnY}V ^mJ KoVbm Amho.qOH$boë¶m§Zm ˶m§À¶m àJVrÀ¶m H«$‘mZo I, II Am{U III ~{jg {‘iVo. ^maVmbm H$moUVohr EH$~{jg {‘iʶmMr g§^mì¶Vm {H$Vr?
CH$b … Ooìhm ^maVmZo n{hbo ~{jg qOH$bo, am{hbobr XmoZ ~{jgo 4P2 àH$mao ‘m§S>Vm ¶oVmV. åhUyZ ^maVmbmn{hbo ~{jg {‘iʶmÀ¶m H«$‘doem§Mr g§»¶m = 4P2 Amho.
^maV qOH$ʶmÀ¶m ‘m§S>UrMr g§»¶m = 3 × 4P2
25
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Probability 119
na§Vy n (S) = 5P3
^maVmbm EImXo ~{jg {‘iʶmMr g§ mì¶Vm =4
25
3
3 PP =
3 4 35 4 3 =
35
ñdmܶm¶ 5.3
1. EH$m Q>monbr‘ܶo 2 bmb Am{U 2 {ndir ’w$bo AmhoV. EH$m ‘wbmZo ghOnUo 3 ’w$bo CMbbr. Va XmoÝhr’w$bo {ndir CMbʶmMr g§ mì¶Vm {H$Vr?
2. 5 춺$s¨À¶m JQ>m‘ܶo eoIa EH$ gXñ¶ Amho. Oa 5 n¡H$s 3 춺$s¨Mr {ZdS> Ho$br Amho. g{‘Vr‘ܶo eoIaAgʶmMr g§ mì¶Vm H$mT>m.
3. 52 nζm§À¶m g§Mm‘YyZ ghOnUo 3 nÎmo CMbbo. gd© VrZ nÎmo amOmMo ¶oʶmMr g§ mì¶Vm {H$Vr?
4. 4 nwéf Am{U 3 {ó¶m ¶m‘YyZ 5 OUm§À¶m g{‘VrMr {ZdS> H$am¶Mr Amho. g{‘Vr‘ܶo Imbrb OUAgʶmMr g§ mì¶Vm {H$Vr? (i) EH$ nwéf (ii) 2 nwéf (iii) 2 {ó¶m (iv)H$‘rV H$‘r XmoZ nwéf
Probability
Empirical probability
Deterministicexperiments
Randomexperiments
Sample Space
Event ACS
Probability of an
event P(E) = n(E)n(S)
Theoretical probability
P(E)= No. of trials in which event happensTotal No. of trials
P(E) = 1
P(E) = 0
P(E E ) =P(E )+P(E )1 2 1 2
P(E) = 1–P(E)–
Certain Event
ImpossibleEvent
Complementaryevents (E)
Mutuallyexclusive events
g§§ mì¶Vm
àm¶mo{JH$ g§§ mì¶Vm VmpËdH$ g§§ mì¶Vm
KQ>ZoV KSy>Z ¶oUmè¶m MmMUtMr g§»¶m
EHy$U MmMUtMr g§»¶m
{ZpíMV à¶moJ ¶mÑpÀN>H$ à¶moJ Z¸$s KQ>Zm
Z‘wZm AdH$meAe³¶ KQ>Zm
H$moQ>r KQ>Zm (E)KQ>ZoMr g§ mì¶Vm
KQ>Zm
nañnamer Ho$di KQ>Zm
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120 UNIT-5
CÎmao
ñdmܶm¶ 5.1
1. (i)16
(ii)26
(iii)16
(iv)56
2. (i)14
(ii)44
(iii)24
(iv)34
3. (i)78
( ii)78
(iii)18
(iv)18
4. (i)536
(ii)3536
(iii)936
(iv)436
(v)79
(vi)1136
5. (i) (ii) (iii) (iv) (v) (vi)
6. (i) (ii) (iii) (iv) (v) (vi)
1550
4750
750
950
850
2550
2652
2652
3952
4852
252
852
2836
7. (i)16
(ii) (iii) (iv) (v) 0 (vi) 1
8. (i) (ii)
9. (i) (ii) (iii) (iv) (v)
10. (i) (ii)
4 6
3 6
3 6
3 0 39
9 39
1 7
6 7
1 7
2 7 7
5
124 144
2 0 144
ñdmܶm¶ 5.2
1. 0.36 2. 3. (i) (ii) 4.
5. 6. 7. 8.
ñdmܶm¶ 5.3
1. 2. 3.
4. (i) 0. (ii) (iii) (iv) 1
24
61 0
15525
27
47
125 2
757
12
46
1 02 5
3 43 6
3 13 5
*******
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¶m KQ>H$m‘wio Vwåhm§bm ¶m§Mo gwb^rH$aU hmoVo.
* à‘m{UV {dMbZmÀ¶m AWm©Mo ñnï>rH$aU.
* à‘m{UV {dMbZ H$mT>ʶmMo gyÌ V¶ma H$aUo.
* à˶j Iam ‘ܶ, J¥hrV ‘ܶ Am{U nm¶ar {dMbZ nÕVrZo
AdJuH¥$V gm‘J«rMm ì¶Ë¶mg Am{U à‘m{UV {dMbZ ¶m§Mr
JUZm ({hemo~) H$aUo.
* MbZ JwUH$mMm Cn¶moJ Am{U AWm©Mo ñnï>rH$aU.
* MbZ JwUH$ H$mT>Uo Am{U {ZH$mbmMo {díbofU H$aUo.
* {ÌÁ¶m§Va I§S>mboI aMUo.
* {ÌÁ¶m§Va I§S>mboImMo {díbofU H$aUo.
* à‘m{UV {dMbZmMm AW©
* à‘m{UV {dMbZ H$mT>ʶmMo gyÌ
* AdJuH¥$V Am{U dJuH¥$V gm‘J«rMm à‘m{UV
{dMbU H$mT>Uo.
* à˶j nÕV
* Iam ‘ܶ nÕV
* J¥hrV ‘ܶ nÕV
* nm¶ar {dMbZ nÕV
* MbZ JwUH$
* {ÌÁ¶m§Va I§S>mboI aMUo
6 g§§»¶m emó (gm§p»¶H$s)(Statistics)
Statistical thinking will one day be as necessaryfor efficient citizenship, as the ability to readand write.
-H.G. Wells
H$mb© {n¶agZ (Karl Pearson)
(1857-1936, B§½b§S>)
H$mb© {nAagZ ho {~«{Q>e g§»¶memók AmhoV.
Vo g§»¶memómÀ¶m AmYw{ZH$ joÌmMm emoY
bmdʶmV AmKmS>rda AmhoV. ˶m§Zr J{UV g§»¶m
emóm‘ܶo {eñV ñWm{nV Ho$br. H$mb© Jm°gZr
dmnaboë¶m "‘ܶ MwH$' ¶m eãXmÀ¶m {R>H$mUr
H$mb© {nAagZZr 1894 ‘ܶo à‘m{UV {dMbZ
hm eãX àW‘ dmnabm.
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122 UNIT-6
¶m nyduÀ¶m dJm©V Amåhr Aä¶mgbobo Amho H$s H$moU˶mhr gm‘mݶ JwUm§H$mÀ¶m {dVaUm‘ܶo à˶oH$ JwUm§H$mMm H$b hm
{dVaUm‘ܶo ‘ܶm^modVr g‘yhmZo {dIyabobo AgVmV. ‘ܶ, ‘ܶm§H$ Am{U ~hþbH$ hr H|$Ðr¶ H$b ‘mnZmMr ‘mno AmhoV. Amåhr
¶mMmhr Aä¶mg Ho$bobm Amho H$s H|$Ðr¶ H$b ‘mnZmMr ‘m{hVr {dVaUm {df¶r nyU© ‘m{hVr XoV Zmhr. CXmhaUmW© EH$m ‘m{bHo$‘ܶo XmoZ
{H«$Ho$Q>nÅz>Zr Ho$boë¶m Ymdm§Mm {dMma H$am.
A 59, 65, 73, 61, 67B 83, 120, 40, 22, 60
XmoÝhr gQ>mVrb JwUm§H$mMm ‘ܶ 65 hm gmaImM Amho. åhUOoM ¶ = 65
A, ¶m gQ>mVrb gd© JwUm§H$ 65 ¶m ‘ܶmOdi AmhoV. Am{U B gQ>mVrb JwUm§H$ 65 ¶m ‘ܶmnmgyZ ‘moR>çm à‘mUmV {dIyabobo
AmhoV.
åhUyZ H|$Ðr¶ H$b ‘mnZ {dVaUm{df¶r ñnï> {MÌ XoV Zmhr. JwUm§H$ ‘ܶmnmgyZ H$em[aVrZo {dIwabobo AmhoV ¶mMo ‘mnZ
H$aʶmMr Amåhmbm JaO Amho.
{dVaUmVrb {dIwaboë¶m gm‘J«r{df¶r ‘m{hVr XoUmè¶m ‘mnZmbm {djonU åhUVmV. Vo {dVaUmVrb JwUm§H$mÀ¶m ~Xbm§Mr {Xem
Am{U à‘mU ¶m§Mo ‘mnZ H$aVo. {djonUmÀ¶m Mma àH$mamn¡H$s n„m MVwW©H$ {dMbZ Am{U ‘ܶ {dMbZ ¶m§Mm Am{U ˶m§À¶m ‘¶m©XoMm
Aä¶mg AmnU AmYr (nydu) Ho$bobmM Amho.
Amåhmbm ‘m{hV Amho H$s n„m XmoZ A§Ë¶ JwUm§H$mda Adb§~yZ AgVmo. Am{U MVwW©H$ {dMbZ ’$º$ 50% JwUm§H$mMm {dMma
H$aVo. ‘ܶ {dMbZ ho n„m Am{U MVwW©H$ {dMbZ ¶m ‘mnZmnojm CÎm‘ g‘Obo OmVo. ‘ܶ {dMbZm‘ܶo AmnU nm{hbo Amho H$s,
JwUm§H$mMo {dMbZ ‘ܶmnmgyZ YZ qH$dm F$U AgVo. na§Vw JUZm ({hemo~) H$aVmZm AmnU F$U qH$‘V gmoSy>Z XoVmo Am{U {dMbZm§Mr
’$º Iar {H$§‘V KoVmo.
’$º$ YZ qH$‘Vr KoʶmgmR>r J{UVm‘ܶo H$moUVmhr CÎm‘ àH$ma Amho H$m?
darb à‘mUo MMm© Ho$bobo CXmhaU {dMmamV ¿¶m.
Scores ( ) 59 65 73 61 67Deviation( ) 6 0 8 4 2
xA
d
Iar qH$‘V d = –6 hr|d| = +6 Am{U d = –4 hr |d| = +4, Aer Koʶm EodOr AmnU ˶m§Mm dJ© H$ê$ Am{U YZ
qH$‘V {‘idy.
d2 = (–6)2 = +36d2 = (–4)2 = +16
AmUIr EH$m KQ>ZoMr MMm© H$am Or {dMbZmMm dJ© Ho$bm AgVm {djonUmMo ‘mnZ H$aʶmg ‘XV H$aVo. A˶§V gm‘mݶ
{dVaU Xe©{dʶmè¶m gQ>m§À¶m gm‘J«rMm {dMma H$am.
12 13 14 15 162 1 0 1 2
xd = 14
Amåhr darb XmoZ KQ>Zm§Mo {ZarjU Ho$bo AgVm {dMbZmMr gamgar 0(eyݶ) AmT>iVo. åhUyZ {djonUmMr ‘mnZmMr nwT>rb
JUZm gwÕm (0)eyݶ Amho? Vo ‘ܶmnmgyZ H$moU˶mhr JwUm§H$mMo {dMbZ Pmbo Zmhr Ago gm§JVo H$m? ho g˶ Zmhr. åhUyZ JwUm§H$mMo
F$U {MÝh gmoSy>Z XoʶmMr JaO Amho. ho {dMbZmMm dJ© H$ê$Z Ho$bo OmVo.
JwUm§H$
{dMbZ d=x-x
x
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Statistics 123
hr {djonU ‘mnZmMr CÎm‘ nÕV Amho. Á¶m ‘ܶo à˶oH$ JwUm§H$m‘Yrb ’$aH$ Am{U ‘ܶ ¶m§À¶m gamgarMm nydu dJ© Ho$bm
OmVmo.
¶m {djonU ‘mnZmÀ¶m nÕVrbm ì¶Ë¶mg Ago åhUVmV. ì¶Ë¶mg hm Zoh‘r YZ AgVmo. Oa Amåhr ì¶Ë¶mgmÀ¶m YZ
qH$‘VrMo dJ©‘wi KoVbo Va Amåhmbm YZ Am{U F$U qH$‘Vr {‘iVmV. ì¶Ë¶mgmÀ¶m YZ dJ©‘wimbm à‘m{UV {dMbZ Ago
åhUVmV. åhUyZ à‘m{UV {dMbZmMr ì¶m»¶m Imbrbà‘mUo H$aVm ¶oVo.
A§H$J{UVr ‘ܶmnmgyZ {dMbZmÀ¶m dJm©À¶m gamgar dJ©‘wimbm qH$dm à‘m{UV [dMbZ ‘ܶ {dMbZmÀ¶m
dJ©‘yimbm Ago åhUVmV.
à‘m{UV {dMbZ ' ' ¶m {MÝhm§Zo Xe©{dVmV. ho {g½‘m Ago dmMVmV. {g½‘m hm J«rH$ eãX Amho. Vo {dVaUmÀ¶m ‘ܶm^modVr
{dIyaboë¶m à˶oH$ JwUm§H$mMo ‘mnZ H$aVo. Vo Zoh‘r gm‘J«r ¶m EH$H$m‘ܶo 춺$ H$aVmV. Vo ‘ܶmnmgyZ {H$Vr {dMbrV Pmbo Amho
Vo XmI{dVo. {Z[ajUmMm Cƒ ar˶m EH$gmaIonUm Am{U g‘mZVm Xe©{dVmo. {dMbZmMm {ZƒV‘ Z‘wZm Xe©{dVmo H$s JwUm§H$ ho
‘ܶmda AmhoV ˶mM à‘mUo {dMbZmMm CƒÎm‘ Z‘wZm gm‘J«r ‘moR>çm në¶mÀ¶m qH$‘VrV {dIyabobr AmhoV Var gwÕm ‘ܶ AJXr
{dê$Õ AgVmo.
AmVm, AmnU {djonU ‘mnZ H$em àH$mao H$mT>VmV Vo Aä¶mgy. Vo åhUOo à‘m{UV {dMbZ.
à‘m{UV {dMbZ H$mT>ʶmMr nÕV (Method of calculating standard deviation)
Amåhmbm ‘m{hV Amho H$s {dVaUmMr gm‘J«r g‘mZar˶m {dIwabobr Amho H$s Zmhr, JwUm§H$ ho nyUmªH$ qH$dm nyU© qH$dm
AnyUmªH$ AmhoV Am{U ‘ܶmMr qH$‘V AnyUmªH$s g§»¶m qH$dm nyUmªH$s g§»¶m Amho. {ZpíMV gyÌ dmnê$Z doJdoJù¶m nÕVrZo
gm‘J«rÀ¶m ñdénmda AmYmarV à‘m[UV {dMbZ H$mTy> eH$Vmo.
AdJuH¥$V gm‘wJ«rMo à‘m{UV {dMbZ à˶oH$ nÕV Aä¶mgy¶m Am{U à‘m{UV {dMbZ H$mT>ʶmMr nÕV g‘OyZ Kody.
¶m nÕVr AdJuH¥$V Am{U dJuH¥$V gm‘J«rbm bmJy nS>Vmo. àW‘ AmnU AdJuH¥$V gm‘J«r Kody Am{U ˶mÀ¶m doJdoJù¶m nÕVr
g‘OyZ Kody Am{U ˶m dJuH¥$V gm‘J«rn¶ªV dmT>dy¶m ì¶Ë¶mg Am{U à‘m{UV {dMbZ Imbrb nÕVr dmnê$Z H$mT>bo OmVo.
AdJuH¥$V gm‘J«rMo à‘m{UV {dMbZ Am{U ì¶Ë¶mg Imbrb nÕVr dmnê$Z à‘m{UV {dMbZ H$mT>bo OmVo.
i) à˶j (WoQ>) nÕV (Direct method) gai nÕV
ii) dmñV{dH$ (Iar) ‘ܶ nÕV (Actual mean method)
iii) J¥hrV ‘ܶ nÕV (Assumed mean method)
iv) nm¶ar {dMbZ nÕV (Step deviation method.)
(i) à˶j (WoQ>) nÕVrZo ì¶Ë¶mg d à‘m{UV {dMbZ H$mT>Uo (Variance and Standard deviation by direct
method)
àW‘ à˶j (WoQ>) nÕVrZo à‘m{UV {dMbZ H$mT>ʶmMo gyÌ V¶ma H$ê$.
ì¶m»¶odê$Z à‘m{UV {dMbZ ho ‘ܶmnmgyZ {dMbZmÀ¶m dJm©Mo YZ gamgar dJ©‘wi Amho.
x1, x2, x3 ...........xn ho JwUm§H$ Am{U x hm ‘ܶ Amho Ago ‘m§Zy
1 2, .......... nx x x x x x ‘ܶmnmgyZMo {dMbZ Amho.
{dMbZmMr ~oarO = x x 2
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124 UNIT-6
‘ܶmnmgyZ {dMbZmMm dJ© 1 2, ..........x x x x x x2 ,1 2, ..........x x x x x x2 AmhoV., .......... nx x x x x x 2
{dMbZm˦m gamgar =x xn
ì¶Ë¶mg qH$dm 2 =2
x xn
à‘m{UV {dMbZ = =2
x xn
(ì¶m»¶odê$Z)
=22 2x xx x
n
=22 2. .x x x x
n n nx x
n
=22
22x nxx
n n =
22 2
2x x xn
Amåhmbm ‘m{hV Amho H$s x2 = x2+x2...........n doim = nx2
=2
2x xn
=2x x
n nxx
n
=22
22x nxx
n n =
22 2
2x x xn
22
S.D or x x=n n
à‘m{UV {dMbZ ho dJ© qH$‘VtÀ¶m ~oaOoMr gamgar Am{U gd© qH$‘VrÀ¶m dJmªÀ¶m ~oaOoMr gamgar ¶m§Mr dOm~mH$s Amho.
ho à˶j (WoQ>) nÕVrZo à‘m{UV {dMbZ H$mT>ʶmÀ¶m nÕVrMo gyÌ Amho.
Amnë¶mbm ‘m{hV Amho H$s, à‘m{UV {dMbZ ho ì¶Ë¶mgmMo YZ dJ©‘wi Amho. ì¶Ë¶mg hm à‘m{UV {dMbZmMm dJ© Amho.ì¶Ë¶mg = ( )2
, Mo gyÌ {bhrbo AgVm Amnë¶mbm ì¶Ë¶mg {‘iob.
ì¶Ë¶mg =
222x x
n n=
22x xn n
à‘m{UV {dMbZ Am{U ì¶Ë¶mg ¶m§À¶m XmoÝhr gyÌm‘ܶo, 'x' åhUOo JwUm§H$ Am{U 'n' åhUOo EHy$U JwUm§H$mMr g§»¶m. ¶mMmAW© Agm hmoVmo H$s ì¶Ë¶mg H$mT>VmZm JwUm§H$mMo ‘ܶmnmgyZMo {dMbZmMr Adí¶H$Vm Zmhr.
Aem [aVrZo à‘m{UV {dMbZ H$mT>ʶmÀ¶m nÜXVrbm à˶j nÜXV åhUVmV.
( {dMbZmÀ¶m dJm©Mr
gamgar = ì¶Ë¶mg Am{U 2 Zo Xe©{dVmV)
qH$dm
qH$dm
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Statistics 125
à˶j (WoQ>) nÕVrZ o à‘m{UV {dMbZ H$mT>ʶmÀ¶m nm¶è¶m :
1. x2 H$mT>Uo
2. x Am{U x2 H$mT>Uo
3. x, x2 Am{U n ¶m§À¶m qH$‘Vr gyÌm‘ܶo dmnaUo.
ì¶Ë¶mg =22x x
n nqH$dm =
22x xn n
Ooìhm JwUm§H$mMm dJ© ghOnUo H$mT>bm OmVmo Voìhm à˶j nÕV dmnaVmV.
CXmhaUm§À¶m gmhmæ¶mZo à˶j nÕV g‘OyZ Kody ¶m.
CXmhaU 1: df© ^am‘ܶo B-8 drÀ¶m {dÚm϶m©Zr bmdboë¶m amonQ>¶m§Mr g§»¶m 2, 6, 12, 5, 9, 10, 7, 4 ¶mgm‘J«rMo à‘m{UV {dMbZ H$mT>m.
CH$b : àW‘ AmnU ¶m JwUm§H$m§Zm ˶m§À¶m MT>˶m H«$‘mV ‘m§Sy> Am{U dJ© H$ê$.
{Q>n: ¶m nÕVr‘ܶo JwUm§H$mZm ˶m§À¶m MT>˶m H«$‘mV ‘m§S>boM nm{hOo Ago Zmhr. na§Vw gm§p»¶H$s‘ܶo gmoS>{dʶmnyduJwUm§H$mZm ˶m§À¶m H«$‘mV ‘m§S>ʶmMm gamd Agbm nm{hOoV.
x 2 4 5 6 7 9 10 12 x = 55
x2 4 16 25 36 49 81 100 144 x2 = 455
¶oWo n = 8, x = 55 Am{U x2 =455
=22x x
n n=
2455 558 8
= 256.88 (6.88) = 56.88 47.33 = 9.55 3.09
gm‘mݶnUo à˶oH$ JwUm§H$ ‘ܶmnmgyZ 3.09 Zo {dMbrV hmoVmo.
à˶j nÕVrÀ¶m ‘¶m©Xm (Limitations of direct method)
à˶j nÕVr‘ܶo ì¶Ë¶mg Am{U à‘m{UV {dMbZ H$mT>ʶmgmR>r x, x2 Am{U n Mr JaO Amho. ˶mZ§VaAmnU x Am{U x2, H$mT>Vmo. ¶m qH$‘Vr gyÌm‘ܶo dmnê$Z ì¶Ë¶mg H$mTy> eH$Vmo. ¶m nÕVr‘Yrb ‘hËdmMrn{hbr JUZm åhUOo JwUm§H$mMm dJ© H$aUo.
Ooìhm JwUm§H$ bhmZ g§»¶oMo Am{U bhmZ nyUmªH$s AgVmV Voìhm hr nÕV ¶mo½¶ Amho.
nyUmªH$s J¥hrV g§»¶oMm dJ© H$aUo gmono Zmhr.
˶m‘wio à˶j nÕV hr ¶mo½¶ Zmhr, Ooìhm
* gm‘J«r ‘moR>r AgVo.
* JwUm§H$ nyUmªH$ ZgVrb Va.
3.09
3 9.553 9
609 55005481
19
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˶m‘wio à‘m{UV {dMbZ H$mT>ʶmMr n¶m©¶r nÕV JaOoMr Amho.
¶mH$S>o gwÕm bj Úm H$s à‘m{UV [dMbZ H$mT>V AgVmZm AmnU JwUm§H$mMo {dMbZ dmnaboboZmhr.
à‘m{UV {dMbZ H$mT>VmZm ‘ܶmnmgyZMo {dMbZ dmnabobr Xþgar nÕV Amho H$m?
AmVm AmnU Xþgè¶m nÕVrMm Aä¶mg H$ê$¶m.Á¶m‘ܶo à‘m{UV {dMbZ H$mT>VmZm JwUmH$mMo ‘ܶmnmgyZ{dMbZ dmnabo OmVo.
(ii) dmñV{dH$ (Iar) ‘ܶ nÕV : (Actual mean method)
Iè¶m ‘ܶ nÜXVrZo à‘m{UV {dMbZ H$mT>ʶmÀ¶m nm¶è¶m.
1 gm‘J«rMm dmñV{dH$ ‘ܶ H$mT>Uo. (A§H$J{UVr ‘ܶ)
2 dmñV{dH$ ‘ܶmnmgyZ à˶oH$ JwUm§H$mMm {dMbZ H$mT>Uoo.
3 {dMbZmMm dJ© H$aUoo.
4 {dMbZmÀ¶m dJm©Mr ~oarO H$mT>Uoo.
5 {dMbZmÀ¶m dJm©Mr ~oarO H$mT>Uo (ì¶Ë¶mg)
6 {dMbZmÀ¶m dJm©À¶m gamgarMo dJ©‘wi H$mT>Uo.
Amåhmbm à‘m{UV {dMbZ {‘iVo.
CXmhaU 2: 10 doJdoJù¶m XdmImݶm‘ܶo OÝ‘ KoVboë¶m ‘wbm§Mr g§»¶m,
9, 12, 15, 18, 20, 22, 23, 24, 26, 31,
hr Amho Va à‘m{UV {dMbZ H$mT>m.
CH$b : x d x x d2
9 –11 121
12 –8 64
15 –5 25
18 –2 4
20 0 0
22 2 4
23 3 9
24 4 16
26 6 36
31 11 121
x = 200 d2 = 400
x
d = x x
d2 =2
x x
d2
2dn
2dn
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A§H$J{UVr ‘ܶ =200
2010
xn
Amnë¶mbm ‘m{hV Amho H$s ' ' ho {dMbZmÀ¶m gamgarMo dJ©‘yi Amho.
=2x x d
n n
=400 40 6.3210
Omo n¶ªV ‘ܶ qH$‘V nyUmªH$ Amho Vmo n¶ªV hr nÕV ¶mo½¶ Amho. Oa ‘ܶ nyUmªH$ Agob Va {dMbZ gwÕmnyUmªH$s AgVo ˶m‘wio ˶m§Mm dJ© H$aUo gmono OmVo.
gm‘J«rMm ‘ܶ x hm nyUmªH$ Zmhr. na§Vw Xem§e g§»¶m Amho Ago g‘Oy. ˶mdoir x x hr gd© {dMbZoXem§e g§»¶m hmoVmV Am{U Xem§emMm dJ© H$aUo ho H§$Q>midmUo H$m‘ Amho.
Aem KQ>Zm‘ܶo, OoWo ‘ܶ nyUmªH$s g§»¶m AmhoV VoWo AmnU à‘m{UV {dMbZ H$mT>ʶmgmR>r AmUIr EH$n¶m©¶r nÕV dmnaVmo {Vbm J¥hrV ‘ܶ nÕV åhUVmV.
¶oWo dmñV{dH$ ‘ܶ H$mT>bo OmV Zmhr. ˶mEodOr AmnU gm‘J«rnmgyZ 'A' ¶m JwUm§H$mMr {ZdS> H$aVmo Aem[aVrZo H$s (x – A) hm ’$aH$ gd© bmhmZ g§»¶m e³¶Vmo YZ AgVmV.
(iii) J¥hrV ‘ܶ nÕV (Assumed mean method)
¶m nÕVr‘ܶo Zmdm§‘ܶo gwM{dë¶m à‘mUo, AmnU
* {dVaUmMm H$moUVmhr JwUm§H$ J¥hrV ‘mZbm OmVmo (e³¶Vmo H$ê$Z ‘ܶmdarb JwUm§H$)
* J¥hrV Yaboë¶m JwUm§H$mnmgyZ à˶oH$ JwUm§H$mMo {dMbZ H$mT>bo OmVo.
' ' H$mT>ʶmÀ¶m J¥hrV ‘ܶ nÕVrÀ¶m nm¶è¶m
1. JwUm§H$ hm ‘ܶ åhUyZ J¥hrV Yam. A2. J¥hrV Yaboë¶m ‘ܶmnmgyZ à˶oH$ JwUm§H$mMo {dMbZ H$mT>m. d = x – A3. {dMbZmMm dJ© H$mT>m. d2 or (x – A)2
4. {dMbZmÀ¶m dJm©Mr ~oarO H$mT>m. d2
5. {dMbZmMr ~oarO H$mT>m. d6. gyÌ dmnam. 22d d
n n7. d2 Am{U d Mr qH$‘Vr dmnam.
8. à‘m{UV {dMbZ H$mT>m.
CXmhaU 3 : EH$m AmR>dS>çm‘ܶo à˶oH$ {Xder EH$m XdmImݶm‘YyZ ~mhoa nS>boë¶m AmOmarbmoH$m§Mr g§»¶m Imbrbà‘mUo {Xbobr Amho.
50, 56, 59, 60, 63, 67, 68 Va à‘m{UV {dMbZ H$mTm.
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128 UNIT-6
CH$b : {Xboë¶m JwUm§H$mMm J¥hrV ‘ܶ A = 60 Amho Ago ‘mZy.
¶m ‘mZboë¶m ‘ܶmnmgyZ à˶oH$ JwUm§H$mMo {dMbZ H$mTy>.i.e., d = x – A
x d = x – A d2
50 –10 10056 –4 1659 –1 160 0 063 3 0967 7 4968 +8 64
n = 7 d = +3 d2 = 239
iv ) nm¶ar {dMbZ nÕV: (step deviation method)
CXmhaU 4 : ‘{hݶmVrb n{hë¶m Xhm {Xdgm‘ܶo emioVrb dmMZmb¶m‘YyZ {Xboë¶m nwñVH$m§Mrg§»¶m Imbrb à‘mUo {Xbobr Amho.
20, 30, 40, 60, 80, 90, 110, 120, 130, 140
Va à‘m{UV {dMbZ H$mT>m.
CH$b :{Xboë¶m JwUm§H$mgmR>r A = 90 ho J¥hrV ‘mZbobo ‘ܶ g‘Oy.
JwUm§H$mMm {dMma H$am. H$moUVr {deofV: AmT>iVo H$m?
bj Úm H$s gd© JwUm§H$mMm 10 hm g‘mB©H$ Ad¶d Amho. Vo gd© 10 À¶m nQ>rVrb AmhoV.
åhUyZ XmoZ JwUm§H$mMm ’$aH$ Am{U J¥hrV ‘ܶ ¶mbm gmYmaU Ad¶d 10 Zo ^mJ Úm Am{U à‘m{UV{dMbZ H$mT>m. ˶m‘yio {hemo~ gmono OmVo.
d =x A
c. ¶m {dMbZmbm nm¶ar {dMbZ Ago åhUVmV.
Ooìhm gm‘J«rMm AmH$ma ’$ma ‘moR>m AgVmo Am{U ˶mbm gmYmaU Ad¶d AgVmo Voìhm AmnU A, ho J¥hrV
‘ܶ KodyZx Ad
Cdmnê$Z OoW o C hm JwUm§H$mMm gmYmaU Ad¶d Amho {dMbZ H$mTy> eH$Vmo.
=22d d C
n nho gyÌ dmnê$Z à‘m{UV {dMbZ H$mT>Vmo.
¶m nÕVrbm nm¶ar {dMbZ nÕV Ago åhUVmV.
22d dn n
2239 37 7
34.14 (0.18)
33.965.83
15
18
A
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Statistics 129
CXmhaU 4 ‘ܶo H$moUVo gmono Amho?
* gmYmaU Ad¶d C H$mT>ʶmnydu d Mm dJ© H$mT>Uo.
* gmYmaU Ad¶d C H$mTy>Z d Mm dJ© H$mT>Uo.
{dMbZmMm gmYmaU Ad¶d H$mT>ë¶mZo Vo à‘m{UV {dMbZ H$mT>ʶmgmR>r H$emàH$mao ‘XV H$aVo ?
nm¶ar {dMbZ nÕVrZo à‘m{UV {dMbZ H$mT>ʶmÀ¶m nm¶è¶m
1 1..EImÚmMm JwUm§H$ ‘ܶ J¥hrV ‘mZUo A
2. à˶oH$ JwUm§H$ Am{U J¥hrV ‘ܶ ¶m‘Yrb ’$aH$ H$mT>Uo. d = x – A
3. JwUm§H$mMm gmYmaU Ad¶d AmoiIUo. C
4. ’$aH$mbm gmYmaU Ad¶dmZo ^mJ XoUo.x Ad
C
5. {dMbZmMm dJ© H$aUo. d2
6. {dMbZmÀ¶m dJm©Mr ~oarO H$mT>Uo. d2
22d dC
n n
x d = x – A nm¶ar {dMbZ d2
x Adc
20 –70 –7 4930 –60 –6 3640 –50 –5 2560 –30 –3 980 –10 –1 190 0 0 0110 20 2 4120 30 3 9130 40 4 16140 50 5 25
n = 10 d = –8 d2 = 174
=22d d
n nC =
2174 810 10
10 = 17.4 6.4 × 10 = 40.9
AmVm n¶ªV AmnU Aä¶mgbobo Amho H$s ì¶Ë¶mg Am{U à‘m{UV {dMbZ ho darb MmanÕVrn¡H$sH$moU˶mhr EH$m nÕVrZo H$mT>bo OmD$ eH$Vo. J¥hrV ‘ܶ nÕV Am{U nm¶ar {dMbZ nÕV.
22
14
7. gyÌ dmnê$Z à‘m{UV {dMbZ H$mT>Uo.
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130 UNIT-6
Anojoà‘mUo doJdoJir nÕV gma»¶mmM gm‘J«rgmR>r Mo doJdoJio CÎma XoV Zmhr. ˶m‘wio gm‘J«rbm ¶mo½¶Aer H$moUVrhr EH$ nÕV dmnabr OmD$ eH$Vo.
{Q>n : J¥hrV ‘ܶ nÕV Am{U nm¶ar {dMbZ nÕV ¶m à˶j nÕVrMo g§{já (gwYmarV) ê$n Amho.
Amnë¶m> gmo¶rgmR>r, ì¶Ë¶mg Am{U à‘m{UV {dMbZ H$mT>ʶmgmR>r AmnU nm¶ar {dMbZ nÜXVrMm
Cn¶moJ H$ê$.
AmVm n¶ªV AmnU AdJuH¥$V gm‘J«rMm ì¶Ë¶mg Am{U à‘m{UV {dMbZ H$mT>ʶmMm Aä¶mg Ho$bobm Amho.
dJuH¥$V gm‘J«r gmR>r gwÕm hrM nÕV bmJy nS>Vo H$m?
dmnaboë¶m gyÌm‘ܶo H$m§hr ~Xb Ho$bo nm{hOoV H$m? ˶m§Mm Aä¶mg H$ê$.
dJuH¥$V gm‘J«rMo à‘m{UV {dMbZ :- (Standard deviation of grouped data)
Amåhmbm ‘m{hV Amho H$s dJuH¥$V gm‘J«rMr ‘m§S>Ur d¡¶{º$H$ JwUm§H$ qH$dm g§ mJ loUrÀ¶m H«$‘m‘ܶo
Ho$br OmD$ eH$Vo. à˶oH$ d¡¶{º$H$ JwUm§H$ qH$dm loUrbm dma§dmaVm (f) AgVo. ‘ܶmMr JUZm ({hemo~) H$aVmZm,
Amnë¶mb m JwUm§H$mMr ~oarO H$mT>mdr b mJVo. ˶mgmR>r Amåhmb m à˶oH$ JwUm§H$ qH$dm g§mJ - loUrÀ¶m
‘ܶmbm dma§dmaVoZo JwUbo nm{hOo åhUOoM. f(x).
¶mM àH$maoo dJuH¥$V gm‘J«rMo à‘m{UV {dMbZ H$mT>VmZm, {dMbZmMr ~oarO H$mT>mdr bmJVo. ˶mgmR>r
Amåhmbm à˶oH$ JwU§mH$mZo [H$§dm g§ mJ loUrÀ¶m ‘ܶ dma§dmaVoZo JwUbo nm{hOo åhUOoM. fd.
åhUyZ fd Am{U fd2 H$mT>bo nm{hOoV.
dJuH¥$V gm‘J«rMo à‘m{UV {dMbZ H$mT>ʶmMo gyÌ Imbrb à‘mUo {Xbobo Amho.
=22fd fd C
n n
AmVm AmnU dJuH¥$V gm‘J«rMo à‘m{UV {dMbZ, nm¶ar {dMbZ nÕVrZo H$mT>y>.
CXmhaU 5 : doJdoJù¶m 5 {OëømVrb 6 {XdgmVrb nmdgmMr Zm|X Imbrb à‘mUo {Xbobr Amho.
nmD$g [‘.‘r. ‘ܶo 35 40 45 50 55
{R >H$ mUm §Mr g §»¶m 6 8 12 5 9
nm¶ar {dMbZ nÕVrZo à‘m{UV {dMbZ H$mT> m.
CH$b : CXmhaUm‘ܶo [‘.‘r. ‘Yrb nmD$g JwUm§H$ (x) Am{U {R>H$mUm§Mr g§»¶m dma§dmaVm (f) Zo Xe©{dVmV.
à‘m{UV {dMbZ gd© Mma nÕVr‘ܶo H$mTy>.
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Statistics 131
x f nm¶ar {dMbZ fd d2 fd2
x AdC
35 6 –2 –12 4 2440 8 –1 –8 1 845 12 0 0 0 050 5 +1 +5 1 555 9 +2 +18 4 36
n=40 fd = +3 fd2 = 73
J¥hrV ‘ܶ A = 45 ¿¶m.
JwUm§H$mMm gmYmaU Ad¶d C = 5 Amho.
22fd fd Cd n
273 35 1.82 5 6.7
40 40
CXmhaU 6 : {dÚm϶mªÀ¶m JQ>mbm J{UV‘Yrb CXmhaUo gm oS >dm¶bm {Xbr ˶m§Zr KoVbobr doi
(goH§$X‘ܶo) {Xbobr Amho Va gm‘J«rMo à‘m{UV {dMbZ H$mT> m.
C-I 0-10 10-20 20-30 30-40 40-50
f 7 10 15 8 10
x f x nm¶ar {dMbZ d2 fd fd2
x AdC
0–10 7 5 –4 16 –28 112
10–20 10 15 –2 4 –20 40
20–30 15 25 0 0 0 0
30–40 8 35 +2 4 +16 32
40–50 10 45 +4 16 +40 160
n=50 fd = +8 fd2 = 344
2 22 344 8 550 50
fd fd Cn n
= 6.88 0.03 5 6.85 5 13.1
¶oVo EH$ Hw$VwhbmMr Jmoï> åhUOo, Ooìhm dJuH¥$V gm‘J«r {Xbobr Agob nm¶ar {dMbZ nÕV WmoS>çm
20
23
48
56
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132 UNIT-6
doJù¶m ñdê$nmV bJoM dmnabr nm{hOo. g§ mJloUr ‘m§S>Ur MT>˶m qH$dm CVa˶m H«$‘mV Ho$br OmVo.¶m KQ>ZoV gmܶm pñWVrV d ¶m ñV§ m‘ܶo J¥hrV ‘ܶ KodyZ O {bhrbo OmVo. Am{U O À¶m da -1, - 2.....Am{U Imbr +1,+2 ...... {bhrbo OmVo.Vwåhr Vnmgm H$s ¶m qH$‘Vr åhUOoM
x Adi
, ¶oWo i hr g§ mJloUrMr ì¶már Amho.am{hboë¶m nm¶è¶m d2, fd, fd2, fd Am{U fd2 ¶m nyduà‘mUoM H$mT>m. à‘m{UV {dMbZ H$mT>ʶmgmR>rVoM gyÌ Oam ~Xb H$ê$Z dmnabo nm{hOo.
22fd fdn n
i.
¶m nÕVrZo H$mTy>.
C I f xx A
di
d2 fd fd2
0–10 7 5 –2 4 –14 28
10–20 10 15 –1 1 –10 10
20–30 15 25 0 0 0 0
30–40 8 35 +1 1 +8 8
40–50 10 45 +2 4 +20 40
n=50 fd = +4 fd2 = 86
22 86 4 1050 50
fd fd in n
= 21.72 (0.08) 10 = 13.1
ñnï >rH$aUmË‘H$ CXmhaUo
CXmhaU 1 : 68, 72, 80, 84, 92, 100 ¶m JwUm§H$mMm ì¶Ë¶mg Am{U à‘m{UV {dMbZ H$mT>m.
CH$b : gd© JwUm§H$m‘ܶo 4 hm gmYmaUAd¶d Amho ¶mMo {ZarjU H$am.
A = 84 hm J¥hrV ‘ܶ KoVbm.
‘ܶ =496
82.66
fxn
24
28
8
6
JwUm§H$ {dMbZ d2
x84
4x
d
68 –4 16
72 –3 9
80 –1 1
84 0 0
92 +2 4
100 +4 16
x = 496 d = –2 d2 = 46
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Statistics 133
Á¶mAWu gm‘Jr«bm gmYmaU Ad¶d 4 Amho Am{U ‘ܶ 82.6 hm nyUmªH$ Zmhr. AmnU nm¶ar {dMbZ nÕVdmnê$Z ì¶Ë¶mg Am{U à‘m{UV {dMbZ H$mTy> eH$Vmo.
d =84
4x A x
C
i.e.,68 84 16
44 4
Am{U B˶mXr
(i) ì¶Ë¶mg 2=2 22 46 2
6 6d dn n
= 7.7 – 0.1
2 = 7.6
(ii) = Variance 7.6 = 2.76
CXmhaU 2: EH$m MmMUr n[aj‘ܶo 60 {dÚm϶mªZr {‘i{dbobo JwU {Xbo AmhoV.
JwU 5-15 15-25 25-35 35-45 45-55 55-65
{dÚm϶mªMr g§§»¶m 8 12 20 10 7 3
{dVaUmMo ‘ܶ à‘m{UV {dMbZ H$mT>m. {ZH$mbmMo ñnï>rH$aU gwÕm H$am.
CH$b : g§ mJ loUrÀ¶m ‘ܶ q~Xÿbm 10 hm gmYmaU Ad¶d Amho. Am{U ‘ܶ nyUmªH$ Zmhr.
nm¶ar {dMbZ nÕVrMm Cn¶moJ H$ê$.
C-I f x fx nm¶ar {dMbZ d2 fd fd2
x AdC
5-15 8 10 80 –2 4 –16 32
15-25 12 20 240 –1 1 –12 12
25-35 20 30 600 0 0 0 0
35-45 10 40 400 +1 1 +10 10
45-55 7 50 350 +2 4 +14 28
55-65 3 60 180 +3 9 +9 27
n = 60 fx = fd = +5 fd2 = 109
1850
(i) ‘ܶ =1850 30.8
60fxn
(nyUmªH$ Zmhr)
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134 UNIT-6
(ii) à‘m{UV {dMbZ =2 22 109 5 10
60 60fd fd Cn n
= 1.81 10 1.34 10
= 13.4
¶mMm AW© à˶oH$ JwUm§H$ ‘ܶmnmgyZ (30.8) gamgar 13.4 Zo {dMbrV hmoVmo.
CXmhaU 3 : 30 JwUm§H$mMm ‘ܶ 18 Am{U à‘m{UV {dMbZ 3 Amho. Va gd© JwUm§H$mMr ~oarO H$mT>m Am{U
gd© JwUm§H$mÀ¶m dJm©Mr ~oarO H$mT>m.
CH$b : JwUm§H$mMr g§»¶m = n = 30
JwUm§H$mMr ‘ܶ = x = 18
Amnë¶mbm ‘m{hV Amho H$s JwUm§H$mMr ~oarO = x = 18 × 30 = 540xx
ngd© JwUm§H$mMr ~oarO = 540
30 JwUm§H$mMo à‘m{UV {dMbZ = = 3
2 =22x x
n n
2218
30x
= 9
2
32430x
+ 9
x2 – 33 × 30 = 9990
gd© JwUm§H$mMm dJm©Mr ~oarO = 9990
{Q>n : Amåhr Aä¶mgbo Amho H$s nm¶ar {dMbZ nÜXV hr A˶§Z gmonr Amho Am{U
à‘m{UV {dMbZ gm oS > {dʶmgmR>r hr AJXr ¶m o½¶ Amho. ˶m‘yio à‘m{UV {dMbZ
gmoS> {dʶmgmR> r BVa VrZ nÜXVr EodOr hr nÜXV AmnU dmnaVmo
ñdmܶm¶ 6.1
1. Imbrb gm‘J«rMo àm‘{UV {dMbZ nm¶ar {dMbZ nÜXVrZo H$mT>m.x 3 8 13 18 23f 7 10 15 10 8
2. nwñVH$mÀ¶m àXe©ZmVyZ 200 {dÚmWm©Zr IaoXr Ho$boë¶m nwñVH$m§Mr g§»¶m Imbrbà‘mUo {Xbobr Amho.
nwñVH$m§Mr g§»¶m 0 1 2 3 4
{dÚm϶mªMr g§»¶m 35 64 68 18 15
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Statistics 135
ì¶Ë¶mg Am{U à‘m{UV {dMbZ H$mT>m.
3. [dkmZ narjo‘ܶo 60 {dÚm϶m©Zr {‘i{dbobo JwU Imbrb à‘mUo {Xbobo AmhoV Va ‘ܶ, ì¶Ë¶mg Am{U
à‘m{UV {dMbZ H$mT>m.
JwUm§H$ (x) 10 20 30 40 50 60
{dÚm϶mªMr g§»¶m(f ) 8 12 20 10 7 3
4. EH$m H$maImݶmVrb 40 H$m‘JmamMr amoOMr (X¡Z§{XZ) ‘Owar Imbrb H$moï>H$mV {Xbr Amho. Va (i) ‘ܶ
(ii) ì¶Ë¶mg (iii) ‘OwarMo à‘m{UV {dMbZ H$mT>m Am{U H$mT>boë¶m qH$‘VrMo ñnï>rH$aU H$am.
‘Owar (ê$n¶m‘ܶo) 30-34 34-38 38-42 42-46 46-50 50-54
H$m‘Jmam§Mr g§»¶m 4 7 9 11 6 3
5. 100 dñVy§Mm ‘ܶ 48 Am{U ˶m§Mo à‘m{UV {dMbZ 10 Amho. gd© dñVy§Mr ~oarO Am{U gd© dñVy§À¶m
dJmªMr ~oarO H$mT>m.
6. EH$m Jm§dmVrb ‘Yy‘oh ê$½Um§À¶m Aä¶mgmdê$Z Imbrb Jmoï>tMo {ZarjU H$am.
d¶ dfm©‘ܶo 10-20 20-30 30-40 40-50 50-60 60-70
ê$½Um§Mr g§»¶m 2 5 12 19 9 3
‘ܶ Am{U à‘m{UV {dMbZ H$mT>m. {ZH$mbm§Mo ñnï>rH$aU gwÕm H$am.
MbZ JwUH$ (Coefficient of Variation)
A Am{U B ¶m XmoZ dó CÚmoJm‘ܶo V¶ma eQ>m©Mo CËnmXZ Ho$bo. XmoÝhr H$maImݶm‘ܶo 6 H«$‘dma {Xdgm‘ܶo
{ebmB© Ho$boë¶m eQ>mªMr g§»¶m Imbrb H$moï>H$m‘ܶo {Xbobr Amho.A 85 102 37 60 72 106B 44 60 55 70 63 56
eQ>mªMr g§»¶m ~Z{dʶmV H$moU˶m H$maImݶmMr gamgar OmñV Amho?
eQ>mªMr g§»¶oMr gamgar H$mT>m.
A - ¶m H$maImݶmMm ‘ܶ =462
776
xn
B - ¶m H$maImݶmMm ‘ܶ =348 586
xn
{ZarjU H$am H$s A ¶m H$maImݶmZo ~Z{dboë¶m eQ>mªÀ¶m g§»¶oMr gamgar hr B nojm OmñV Amho.
H$nS>çmÀ¶m KmD$H$ {dH«o$˶mbm {Z¶{‘V eQ>© nwa{dʶmgmR>r H$maImݶmbm Amkm Km¶Mr Amho Ago g‘Om.‘mbH$mbm OmñV MbVm (nardV©ZerbVm) ZgVmZm nwadR>çm‘ܶo gmV˶ (gagVm) hdo Amho.
Va A Am{U B ¶m H$maImݶmn¡H$s ‘mbH$mZo H$moUmMr {ZdS> H$amdr?
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136 UNIT-6
CËnmXZmV gmV˶ Am{U CÎm‘ nwadR>m ho ’$º$ Cƒ gamgar qH$‘Vr nojm CÎm‘ AgUmam H$maImZm ‘m{hVrMmAgVmo.
Amnë¶m X¡Z§{XZ OrdZm‘ܶo Ago AZoH$ àg§J ¶oVmV OooWo H$m¶© gmV˶ Am{U CËnmXZm‘ܶo gmV˶ ho ’$º$‘moR>çm g§»¶oZo ‘mnmnojm OmñV gmo¶rñH$a AgVo.
CXmhaUmW© :
* {H«$Ho$Q> gm‘mݶm‘ܶo ’$b§XmO qH$dm Jmob§XmO {ZdS>Uo.
* amï´>r¶ ñVamdarb narjm ñnY}gmR>r {dÚm϶mªMr {ZdS> H$aUo.
* Am°qb{nH$gmR>r YmdnÅz>§Mr {ZdS> H$aUo.
* nmbo mÁ¶m qH$dm ’w$bmMm {dH«o$Vm {ZdS>Uo.
gagVm (gmV˶) Am{U MbVm (n[adV©ZerbVm) H$emàH$mao H$mT>br OmVo.
¶m H$maUmgmR>r gm§p»¶H$s‘ܶo AmnU MbZ JwUH$ (C.V) H$mT>Vmo.
MbZ JwUH$ ho {djonU ‘mnZmer g§~§{YV Amho. ho dma§dmaVm {dVaUmMm A§H$J{UVr ‘ܶAm{U à‘m{UV {dMbZmda AmYmarV Amho. ¶mbm g §~ §{YV à‘m{UV {dMbZ Ago gwÕmåhUVmV.
MbZ JwUH$mMr ì¶m»¶m
MbZ JwUH$ =C.V = 100à‘m{UV {dMbZA§H$J{UVr ‘ܶ
Aer H$aVmV.
C.V = 100x
MbZ JwUH$mdê$Z Ago AmT>iVo H$s.
* ho Q> o$dmar (eoH$S>odmar) V 춺$ H$aVmV.
* ho EH$H$mnmgyZ ñdV§Ì AmhoV.
* ho ‘ܶ x Am{U à‘m{UV {dMbZmdê$Z ( ) emoYVmV.
* ho {dVaÊmmMo gmV˶ Am{U MbVm emoYVo.H$maImZm A
JwUm§H$ x d = x – A d2
37 –48 230460 –25 62572 –13 16985 0 0102 +17 289106 +21 441n=6 d = 48 d2=3828
H$maImZm B
JwUm§H$ x d = x – A d2
44 –16 25655 –5 2556 –4 1660 0 063 +3 970 +10 100
n=6 d = –12 d2=406
25
13
86
38
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Statistics 137
na§Vw MbZ JwUH$ dmnê$Z gmV˶ Am{U MbVm H$er {ZpíMV Ho$br OmVo? C.V H$er H$mT>br OmVo.
nwÝhm EH$Xm H$maImZm A Am{U B ¶m§Mm {dMma H$ê$.
Amnë¶mbm ˶m§Mr ‘ܶ qH$‘V ‘m{hV Amho, AmVm AmnU à‘m{UV {dMbZ H$mTy> Am{U Z§Va MbZ JwUH$
(C.V) H$mTy>.
(1) Am{U (2), ¶m§Mr VwbZm Ho$br AgVm Amnë¶mbm Ago {XgyZ ¶oVo H$s H$maImZm B Mm MbZ JwUH$
hm H$maImZm A À¶m MbZ JwUH$mnojm H$‘r Amho.
A = 60 ‘mZy
=22fd fd
n n
=
2406 126 6
= 67.67 4
= 63.67
= 7.98
C.V = 100x
=7.98 10058
C.V = 13.76
H$maImZm B Zo ~Z{dboë¶m eQ>mªMm MbZ JwUH$
13.76 Amho. .....(2)
A = 85 ‘mZy
=22fd fd
n n
=23829 48
6 6
= 638.17 64
= 574.17
= 23.96
C.V = 100x
=23.96
10077
C.V = 31.12
H$maImZm A Zo ~Z{dboë¶m eQ>mªMm MbZ JwUH$
31.12 Amho ...(1)
Ooìhm MbZ JwUH$
OmñV AgVmo
H$‘r AgVm o
{Xbobr gm‘J«r H$‘r(gag) gmV˶nyU© Amho.
{Xbobr gm‘J«r OmñVgag gmV˶nyU © Amho
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138 UNIT-6
åhUyZ AmnU åhUy H$s eQ>© ~Z{dʶm‘ܶo H$maImZm B Mo gmV˶ H$maImZm A nojm OmñV Amho.
darb MM}dê$Z AmnU Agm {ZîH$f© H$mTy> H$s XmoZ qH$dm A{YH$ g‘whmÀ¶m gm‘J«rMm MbZ JwUH$
gagVm (gmV˶) VwbZm H$aʶmg Amnë¶mbm ‘XV H$aVo.
ñnï >rH$aUmË‘H$ CXmhaUo
CXmhaU 1 :‹ Aê$U Am{U ^aV ¶m XmoZ {H«$Ho$Q> IoimSy>Zr 15 S>mdm§‘ܶo 1050 Am{U 900 Ymdm
Ho$ë¶m AmhoV ˶m §Mm MbZ JwUH$ AZwH «$‘o 4.2 Am{U 3.0 Amho. Va Ymdm O‘{dʶmV H$m oU
Mm §Jbm Amh o? Hw$UmMm Ioi A{YH$ gag (gmV˶nyU©) Amho?
CH$b : Ioiboë¶m gm‘ݶm§Mr g§»¶m n = 15
Aê$UÀ¶m JwUm§H$mMr (IoimMr) gamgar1050 7015
x
^aVÀ¶m JwUm§H$mMr (IoimMr) gamgar900 6015
x
x Am{U dmnê$Z MbZ JwUH$ H$mTy>.
IoimSy> ‘ܶ à‘m{UV {dMbZ C.V = 100x
Aê$U 70 4.24.2 100 6.070
^aV 60 3.03.0
100 5.060
(i) Aê$UMm gamgar JwUm§H$ hm ^aVÀ¶m gamgar JwUm§H$mnojm OmñV Amho, ˶m‘wio Aê$U Ymdm
O‘{dʶmV Mm §Jbm Amho.
(ii) ^aVMm MbZ JwUH$ hm Aê$UÀ¶m MbZ JwUH$mnojm H$‘r Amho. åhUyZ ^aV hm OmñV gag
(gmV˶nyU©) Amho.
CXmhaU 2 : Imbrb {dVaUmMm à‘m{UV {dMbZ Am{U MbZ JwUH$ H$mT>m.
JwU (x) 10 20 30 40 50
{dÚm϶mªMr g§»¶m (f) 4 3 6 5 2
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Statistics 139
JwUm§H$ dma§dmaVm fx ‘ܶmnmgyZMo {dMbZ d2 fd2
x f d x x
10 4 40 –19 361 1444
20 3 60 –9 81 243
30 6 180 +1 1 6
40 5 200 +11 121 605
50 2 100 +21 441 882
n = 20 fx = 580 fd2 = 3180
(i) A§H$J{UVr ‘ܶ =580
2920
fxxn ‘ܶ = 29x =
(ii) =2 3180 159 12.61
20fdn
= 12.61
(iii) C.V =12.61
100 10029x
= 1261 43.4829
C.V = 43.48
ñdmܶm¶ 6.2
1. Imbrb gm‘J«rMm MbZ JwUH$ H$mT>m. 40, 36, 64, 48, 52.
2. gm‘J«rÀ¶m g‘whmMm MbZ JwUH$ 45 Am{U à‘m{UV {dMbZ 2.5 Amho Va ‘ܶ H$mT>m.
3. ^aVrgmR>r Amboë¶m JQ>mVrb 100 C‘oXdmam§Mr emararH$ MmMUr KoʶmV Ambr. ˶m§Mr gamgar C§Mr163.8 g|.‘r. d MbZ JwUH$ 3.2 Amho. Va ˶m§À¶m C§MrMo à‘m{UV {dMbZ {H$Vr?
4. Oa n = 10, 12x = Am{U x2 = 1530, Va MbZ JwUH$ H$mT>m.
5. XmoZ ‘m{bH$m§Mm MbZ JwUH$ 58 Am{U 69 Amho. ˶m§Mo à‘m{UV {dMbZ 21.2 Am{U 51.6 Amho. Va˶m§Mm A§H$J{UVr ‘ܶ H$mT>m.
6. A ¶m ’$b§XmOmÀ¶m à˶oH$ S>mdmVrb gamgar Ymdm 64 Am{U ˶mMo à‘m{UV {dMbZ 18 Ymdm Amho.VgoM B ’$b§XmOmMr Ymdm§Mr gamgar 43 Am{U à‘m{UV {dMbZ 9 ho gma»¶mM S>mdm‘ܶo AmhoV. Va’$b§XmOmMo gm‘W© Am{U gagVm (gmV˶) ¶mMr MMm© H$am.
7. A Am{U B, XmoZ ~m§YH$m‘ H§$nZrMr gamgar ‘Owar ê$n¶m‘ܶo Am{U à‘m{UV {dMbZ Imbrb à‘mUo{Xbobo Amho.
H§$nZr gamgar ‘Owar ‘OwarMo à‘m{UV {dMbZ
ê$n¶m‘ܶo ê$n¶m‘ܶo
A 3450 6.21
B 2850 4.56
d¡¶{º$H$ ‘Owar‘ܶo H$moUVr H§$nZr Mb Amho Vo emoYm.
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140 UNIT-6
{ÌÁ¶m§Va I§S>mboI (Pie charts)Amåhr Aä¶mgbobo Amho H$s g§»¶mË‘H$ gm‘J«r {MÌ qH$dm AmboI ñdê$nmV Xe©{dbr OmVo. ñ‘aU H$am
H$s g§»¶mË‘H$ gm‘J«r {MÌmH¥$Vr, aofm AmboI, ñV§ mboI, {hñQ>moJ«m‘ Am{U {ÌÁ¶m§Va I§S>mboImZo Xe©{dVmV.{ÌÁ¶m§Va I§S>mboIm‘ܶo ‘m{hVr dVw©im‘ܶo {d^mJbr OmVo. åhUyZ {ÌÁ¶m§Va I§S>mboImbm dVw©i AmboI
Agohr åhUVmV. {ÌÁ¶m§Va I§S>mboI hm H$mhr ^mJm§Mr dmQ>Ur qH$dm {d^mJUrMm àH$ma Amho.{ÌÁ¶m§Va I§S>mboIm‘ܶo dVw©i g§nyU© gm‘J«r (‘m{hVr) Xe©{dVo, Z§Va à˶oH$ ^mJmMr ‘m{hVr hr dVw©i
‘ܶmnmgyZ R>am{dH$ H$moZ H$aVo åhUyZ à˶oH$ ^mJmMr ‘m{hVr hr H|$Ðr¶ H$moZm‘ܶo EH$ ^mJ Xe©{dVo. åhUyZ{ÌÁ¶m§Va I§S>mboImbm I§S>m AmboI (sector Graph) Agohr åhUVmV.
g§»¶mË‘H$ gm‘J«rMo a¸$‘, ‘VXmZ, ‘m{hVr, ~OoQ>, hdm‘mZ bmoH$g§»¶m B˶mXtMo n¥W:H$aU H$aʶmgmR>r{ÌÁ¶m§Va I§S>mboImMm Cn¶moJ hmoVmo.
Imbrb CXmhaUmMm Aä¶mg H$am.CXmhaU 1: dJm©‘ܶo 36 {dÚmWu AmhoV.
Imbrb H$moï>H$ Vo emiobm H$go ¶oVmV ho XmI{dVo.MmbV gm¶H$b ~g H$maJmS>r emim ìh°Z12 8 3 4 9
{ÌÁ¶m§Va I§S>mboI‘ܶo hr ‘m{hVr H$er Xe©{dVmV ˶mMm Aä¶mg H$ê$.gd© 36 {dÚm϶mªMm JQ> dVw©im‘ܶo Xe©dm¶Mm Amho.Amnë¶mbm ‘m{hV Amho H$s dVw©imÀ¶m H|$Ðm‘ܶo 360° Mm H$moZ AgVmo.åhUyZ 36 {dÚm϶m©Zm 360° ‘ܶo Xe©{dbo nm{hOo. à˶oH$ {dÚmWu hm ˶mZo ~Z{dboë¶m H|$Ðr¶ H$moZmÀ¶mà‘mUmV AgVmo.Oa 36 {dÚm϶mªMm g§nyU© JQ> 360° er g§~§YrV AgVmo Va à˶oH$ {dÚm϶mªMm g§~§YrV H$moZ
36036
= 10° 12 {dÚmWu MmbV ¶oVmV ˶m§Mm H$moZ 12 × 10° = 120°. ¶mMm AW© 12 MmbV ¶oUmao {dÚmWu
H|$ÐmnmgyZ 120° Mm H$moZ dVw©im‘ܶo Xe©{dVmV.¶mMàH$mao doJdoJù¶m nÕVrZo ¶oUmè¶m {dÚmWmªMr g§»¶m Am{U ˶m§Zr H|$Ðmer Ho$bobm H$moZ Imbrb H$moï>H$mV{Xbobm Amho.
emiobm ¶oUmè¶m {dÚm϶mªMr g§»¶m {dÚm϶mªMm H|${ж H$moZ
{dÚm϶mªMo àH$ma
MmbV 121236 × 360º =120°
gm¶H$b 8836
× 360º = 80°
~g 3336
×360º = 30°
H$maJmS>r 4436
×360º = 40°
emim ìh°Z 9936
×360º = 90°
36 360°
Car
30° Bicycle40°
Van80°
Bus
Walk
120°
emim ìh°Z
90°MmbV
gm¶H$b
H$maJmS>r
gm¶H$b
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Statistics 141
darb à‘mUo dV©wimÀ¶m H$moZm§Mr aMZm H$ê$Z hr ‘m{hVr {ÌÁ¶m§Va I§S>mboIm‘ܶo Xe©dy eH$Vmo.
{ÌÁ¶m §Va I§S >mb oI aMʶmÀ¶m nm¶è¶m.
nm¶ar 1 : EHy$U ^mJm§Mr g§»¶m ({dÚmWu) 12 + 8 + 3 + 4 + 9 = 36
nm¶ar 2 : à˶oH$ ^mJmMm H|$ÐñW H$moZ H$mT>m. (darb H$moï>H$mV Xe©{dë¶m à‘mUo)
nm¶ar 3 : R>am{dH$ {ÌÁ¶oMo dVw©i H$mT>m.
nm¶ar 4 : H§$nmg dmnê$Z dVw©imÀ¶m H|$Ðmer H|$ÐñW H$moZ H$mT>m.
nm¶ar 5 : H$moZ H$mT>m Am{U à˶oH$ ^mJmÀ¶m KQ>H$mMo Zm§d {bhm.
CXmhaU 2 : O§Jbm‘ܶo EH$ Mm¡ag {H$bmo‘rQ>a joÌ’$imÀ¶m ^mJmV AmT>iUmè¶m Mma ‘hËdmÀ¶m dZñnVr Imbrb
H$moï>H$mV {Xboë¶m AmhoV. {ÌÁ¶m§Va I§S>mboI H$mT>m.
gmJdmUr bmHy$S> amP bmHy$S> XodXma bmHy$S> {Zb{Jar bmHy$S>
360 300 385 135
CH$b : {ÌÁ¶m§Va I§S>mboI H$mT>ʶmÀ¶m nm¶è¶m dmnam.
nm¶ar 1 : EHy$U dZñnVtMr g§»¶m ¿¶m 360 + 300 + 285 + 135 = 1080
nm¶ar 2 : à˶oH$ àH$maÀ¶m dZñnVtMm H|$ÐñW H$moZ H$mT>m.
dZñnVrMm àH$ma dZñnVtMr g§»¶m H|$ÐñW H$moZ
gmJdmUr bmHy$S> 360360
1080 × 360º = 120°
amoP bmHy$S> 300300
1080× 360º = 100°
XodXma bmHy$S> 285285
1080× 360º = 95°
{Zb{Jar bmHy$S> 1351351080
× 360º = 45°
1080 360°
nm¶ar 3 : R>am{dH$ {ÌÁ¶oMo dVw©i H$mT>m.
nm¶ar 4 : H$moï>H$m‘ܶo H$mT>boë¶m H$moZmZwgma H|$ÐñW H$moZ aMm.
nm¶ar 5 : H$moZmV {d^mJm Am{U à˶oH$ ^mJm‘ܶo dZñnVrMo àH$ma {bhm.
AmVm n¶ªV AmnU {Xboë¶m g§»¶mË‘H$ gm‘J«rMm {ÌÁ¶m§Va I§S>mboI
aMʶmMm Aä¶mg Ho$bobm Amho.
AmVm AmnU {Xboë¶m {ÌÁ¶m§Va I§S>mboImbm dmMyZ ‘m{hVrMo ñnï>rH$aU
H$ê$.
Rose wood
Teak
woo
d
Eucalyp
tus
Devadaru
120° 100°
45° 95°
gmJd
mUr b
mHy$S>
amoP bmHy$S>
[ZbJra
r bmHy$S
>
XodXma
bmHy$S>
45°
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142 UNIT-6
{ÌÁ¶m§Va I§S>mboImMo dmMZ A{U {díbofU:
CXmhaU 3 : df©^amVrb Hw$Qw>§~mMm IM© Am{U ~MV Xe©{dUmam {ÌÁ¶m§Va I§S>mboI Imbrb à‘mUo XmI{dbobm Amho.
{ÌÁ¶m§Va I§S>mboImMm Aä¶mg H$ê$Z Imbrb àíZm§Mr CÎmao Úm.
(i) Oa Hw$Q>w>§~mMo EHy$U CËnÞ <75,000 Amho. Va ‘wbm§À¶m {ejUmgmR>r Ho$bobm IM© {H$Vr?
(ii) H$nS>çmgmR>r CËnÞmÀ¶m {H$Vr Q> o$ a¸$‘ IM© Ho$br?
(iii) Hw$Qw>§~mÀ¶m CËnÞmMr ~MV {H$Vr?
(iv) AmhmamgmR>r H$obobm IM© hm KamgmR>r Ho$boë¶m IMm©nojm {H$VrZo OmñV Amho?
(v) Ka> IM© Am{U XiUdiU IM© ¶m‘Yrb ’$aH$ {H$Vr Amho?
CH$b : (i) {Xbobo Hw$Q>w>§~mMo EHy$U CËnÞ = < 75,000
‘wbm§À¶m {ejUmgmR>r Ho$bobm IM© CËnÞmÀ¶m 12% Amho.
‘wbm§À¶m {ejUmgmR>r Ho$bobm IM© =12100 × 75,000 = < 9,000
< 75,000, n¡H$s ‘wbm§À¶m {ejUmgmR>r Ho$bobm IM© < 9,000 Amho.
(ii) H$nSçmgmR>r Ho$bobm IM© CËnÞmÀ¶m 10% Amho.
H$nSçmgmR>r Ho$bobm IM© =10100
× 75000 = <7500
H$nSçmgmR>r Ho$bobm IM© = < 7500
(iii) {Xbobo, ~MV Ho$bobo CËnÞ 15% Amho.
~MV Ho$bobr a¸$‘ =15100
× 75,000 = 11,250
75,000, CËnÞmn¡H$s Ho$bobr ~MV <11,250 Amho.
(iv) Amhmamda Ho$bobm IM© 23% Am{U Ka IM© 15% {Xbobm Amho.
AmhmamgmR>r Ho$bobm IM© =23
100× < 75,000 = < 17,250
KamgmR>r Ho$bobm IM© =15100 × < 75,000 = < 11,250
Amhmamda Ho$bobm IM© - KamgmR>r Ho$bobm IM© = <17,250 – <11,250 = < 6,000
Savings15% O
thers20%
Transport20%12%
childreneducation
Housing15%
Clothing10%
Food 23%Amhma
23%~MV
BVa 20%
XiU diU 20%‘wbm§Mo
{ejU 12%
KamgmR> r
15%
H$nS>çm§gmR>r 10%
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Statistics 143
AmhmamgmR>r Ho$bobm IM© ê$.6000 Zo KamgmR>r Ho$boë¶m IMm©nojm OmñV Amho.
(v) KamgmR>r Ho$bobm IM© = <11,250
XiUdiUmgmR>r Ho$bobm IM © =5
100× < 75,000 = < 3,750
XiUdiU IM© Am{U Ka IM© ¶m‘Yrb ’$aH$
<11,250 – `< 3,750 = `< 7,500
CXmhaU 4 : Mma eham§Mr bmoH$g§»¶m Xe©{dbobm {ÌÁ¶m§Va I§S>mboI Imbrb à‘mUo XmI{dbm Amho. {ÌÁ¶m§Va
I§S>mboI dmMm Am{U 'S' ehamMr bmoH$g§»¶m H$mT>m.
CH$b : 'S' ¶m ehamÀ¶m {d^mJmMm H|$ÐñW H$moZ x° ‘m§Zy.
Voìhm 120° + 96° + 60° + x° = 360°
276° + x° = 360°
x° = 360° - 276° = 84°
120° À¶m H$moZmÀ¶m ^mJmer =100 bmI g§~§YrV bmoH$g§»¶m
84° À¶m H$moZmÀ¶m ^mJmer g§~§YrV bmoH$g§»¶mA sector of 84° corresponds 5
= 84 × lakh = 70 lakh6
S ¶m ehamMr bmoH$g§»¶m = 70 bmI
ñdmܶm¶ 6.3
I. Imbrb gm‘J«rMm {ÌÁ¶m§Va IS>mboI H$mT>m.
1. Amnë¶m AmdS>rÀ¶m Ioim‘ܶo gm‘rb hmoUmè¶m {dÚm϶mªMr g§»¶m {Xbr Amho.
IoimMo Zm§d ’y$Q>~m°b Q>o{Zg ìhm°br ~m°b hm°H$s ~mñHo$Q> ~m°b BVa
{dÚm϶mªMr g§»¶m 35 14 10 6 5 2
2. ghbr‘ܶo {R>H$mUm§Zm oQ> XoʶmgmR>r dJm©‘ܶo gd}jU KoʶmV Ambo Am{U à˶oH$ {R>H$mUm§Mr {ZdS>
Ho$boë¶m {dÚm϶mªMr g§»¶m {Xbr Amho.
{R>H$mU åh¡gê$ {dO¶nya JmoH$U© {MÌXþJ©
{dÚm϶mªMr g§»¶m 14 6 2 18
?60°
120°96°
R
SQ
P
100 lakhbmI
}
bmI bmI
à¶ËZ H$am:
Q A{U R ehamMr bmoH$g§»¶m H$mT>m.
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144 UNIT-6
3. EH$m IoS>çmVrb bmoH$m§Zr doJdoJù¶m àH$maMo gm~U dmnaboë¶m§Mo gd}jUmZo Aä¶mgbo.
gm~UmMm àH$ma A B C BVa
IoS>çmVrb bmoH$m§Mr Q> o$dmar 50% 30% 15% 5%
II. Imbr {Xboë¶m {ÌÁ¶m§Va I§S>mboImMm Aä¶mg H$ê$Z à˶oH$ KQ>ZoV {Xboë¶m àíZm§Mr CÎmao Úm.
1. EH$m {R>H$mUÀ¶m eoVmVrb dm{f©H$ CËnÞmMm {ÌÁ¶m§Va I§S>mboI {Xbobm
Amho
Oa EHy$U CËnmXZ 8100 Q>Z Amho
Imbrb àíZm§Mr CÎmao Úm.
(i) ^mV, ZmMUm, D$g Am{U BVam§Mo Q>Zm‘ܶo CËnmXZ {H$Vr?
(ii) ZmMʶmMo CËnmXZ ^mVmnojm {H$Vr Q>¸o$ A{YH$ Amho?
(iii) doJdoJù¶m dfm©Vrb D$gmMo CËnmXZ 2400 Q>Z Agob Va ^mVmMo
CËnmXZ {H$Vr?
2. doJdoJù¶m ñVamVrb bmoH$m§Mr ‘wbmIV KoʶmV Ambr Am{U H$moUVo XÿaXe©Z H$m¶©H«$‘ gdm©V OmñV
AmdS>VmV Ago {dMmaʶmV Ambo. ˶mMm {ZH$mb {ÌÁ¶m§Va I§S>mboImV
XmI{dbobm Amho.
àíZm§Mr CÎmao {bhm.
(i) ‘wbmIV KoVboë¶m ‘ܶo nmhÊmmè¶m§Mm AnyUmªH$ {H$Vr ?
(a) M°Zob 3 (b) M°Zob 5
(c) M°Zob 1 (d) M°Zob 2
(e) M°Zob 9
(ii) Oa VoWo 200 bmoH$ AgVrb Va {H$Vr bmoH$mZr à˶oH$ M°Zob nm{hbo?
******
Ragi100°
140°
OtherRice
40°80°
Suga
r ca
ne
Chann
el1
Channel
9
90°
Channel2
45°Channel
3
90°Channel
5
30°
M°Zob 1
108
0 M°Zob 9
M°ZobM°Zob 72
0
M°Zob
D$g ZmMUm
^mVBVa
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Statistics 145
Statistics
Standard deviationv
Variance2v
Coef?cient ofvariation Pie charts
Ungrouped data Grouped data
22x xn n
22fx fxn n
2dn
2fdn
22fd fdn n
22fd fdn n
22fd fd Cn n
Step deviationmethod
22fd fd Cn n
. . 100C Vx
Constructingpie charts
Interpretationof pie charts
C.V. is more C.V. is less
Data is lessconsistent
Data is moreconsistent
Coefficient ofvariation
-
g§»¶m emó
à‘m{UV {dMbZ ì¶Ë¶mg MbZ JwUH$ {ÌÁ¶m§Va I§S>mboI
Ad{J©H¥$V gm‘J«r dJuH¥$V gm‘J«r{ÌÁ¶m§Va I§S>mboI
aMUo{ÌÁ¶mZ§Va I§S>mboImMo
{ddaU H$aUo
à˶j nÕV OmñV Agob Va H$‘r Agob Va
dmñV{dH$ ‘ܶ nÕV
‘m{hVr ApñWa(Mb)AgVo
‘m{hVr [ñWa(gag)AgVo
J¥{hV ‘ܶ nÕV
nm¶ar {dMbZ nÕV
ñdmܶm¶ 6.11) 6.32 2) v = 1.23, = 1.107 3) v = 0.179, = 13.4
4) ‘ܶ =41.7, V = 1.94 = 5.58 5) x = 4800, x2 = 2,40,4000 6) ‘ܶ = 42.84, = 11. 93
ñdmܶm¶ 6.2
1) C.V = 20.41 2) X = 5.55 3) = 5.2 4)C.V = 25 5) X = 36.55 Am{U 74.646) A = 28.125, B = 20.93 7) A = 0.18, B = 0.16
ñdmܶm¶ 6.3
II 1) (i) ZmMUm = 2250 Q>Z, D$g = 1800 Q>Z, Vm§Xÿi = 900 Q>Z, BVa = 3150 Q>Z
(ii) ZmMʶmMr Q>¸o$dmar = 16.66%, (iii) 1,200
2. (i) ( a)18 , (b)
340
, (c)310 (d)
14 , (e)
14
(ii) (a) 25 (b) 15 (c) 60 (d) 50 (e) 50
******
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¶m KQ>H$mÀ¶m Aä¶mgmZo ¶m§Mo gwb^rH$aU hmoVo.
* gOmVr¶ Am{U {dOmVr¶ H$aUr AmoiIUo.
* {ÛnXr H$aUrMr ì¶m»¶m
* gOmVr¶ Am{U {dOmVr¶ H$aUrVrb ’$aH$.
* gOmVr¶ H$aUrMr ~oarO Am{U dOm~mH$s.
* {Xboë¶m H$aUrMm JwUmH$ma H$mT>Uo.
* H$aUrer g§~§{YV ~oarO, dOm~mH$s Am{U JwUmH$mamMr
CXmhaUo gmoS>{dUo.
* {ÛnXr H$aUtMm JwUmH$ma H$mT>Uo.
* H$aUr, {ZamgH$ H$aʶmÀ¶m nÜXVrMo dU©Z H$aUo.
* {Xboë¶m H$aUrMm H$aUr {ZamgH$ H$aUo.
* A§emMm qH$dm N>oXmMm H$aUr {Zamg H$éZ gai én
XoUo.
* H$aUrMo àH$ma* {ÛnXr H$aUr
* H$aUrdarb {H«$¶m * {ÛnXr H$aUtMm JwUmH$ma* H$aUr {Zamg* N>oXmMm H$aUr {ZamgH$* A§emMm H$aUr {ZamgH$
7
Mathematics is concerned only with theenumeration and comparision of relations.
-Carl Friedrich Gauss
H$aUr (Surds)
Ab- ImodmarP‘r
Ab-IodmarP‘rZr n [a‘o¶g§»¶mZm A°mS>r~b (EoHy$ ¶oUmao) åhQ>boAm{U Z§Va ˶m§Zm H$aUr (‘wHo$,EoHy$ Z¶ oUma o) Ago Z § md {Xbo.h oM eãX{’$~moZm³H$sZr gwÜXm dmnabo. na§Vw hodJ©‘yi Zgboë¶m g§»¶ogmR>r dmnabo.
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gOmVr¶ d {dOmVr¶ H$aUr ( like and unlike surds )
Amåhr ¶mnyduM H$aUr~Ôb Aä¶mgbobo Amho. Imbrb gmaUrVrb g§{jßV énmVrb H$aUrMo H$aUr H«$‘ dH$aUrnX nmhm.
A.Z§ H$aUr g§{jßV én H$aUr H«$‘ H$aUrnX
1. 3 3 2 3
2. 12 2 3 2 3
3. 75 5 3 2 3
4. 3 27 9 3 2 3
5. 22 3x 2 3x 2 3
da {Xboë¶m gd© g§{jßV énmVrb H$aUr‘ܶo H$aUr H«$‘ d H$aUrnX gmaIoM Amho. Aem àH$maÀ¶mH$aUrZm gOmVr¶ H$aUr Ago åhUVmV.
g§{jßV énmVrb EH$mM H«$‘mÀ¶m Am{U gmaIrM H$aUrnXo AgUmè¶m H$aUrÀ¶m JQ>mg gOmVr¶ H$aUr(like surds)Ago åhUVmV.
AmVm Imbr {Xboë¶m gmaUrVrb H$aUtMm JQ> nmhm Am{U gmaUr nyU© H$am.
JQ> H$aUr g§{jßV én H$aUr H«$‘ H$aUrnX gmaIm doJdoJim gmaIm doJdoJim
1. 8, 12, 20, 54 2. 3 450, 54, 32
3. 43 518, 24, 64, 192
da {Xboë¶m gmaUr‘ܶo AmnU nmhÿ eH$Vmo H$s
JQ> 1 ‘ܶo H$aUr H«$‘ gmaIm Amho, H$aUrnX doJdoJio Amho.
JQ> 2 ‘ܶo H$aUr H«$‘ doJdoJio AmhoV, H$aUrnX gmaIo Amho.
JQ> 3 ‘ܶo H$aUr H«$‘ doJdoJio AmhoV, H$aUrnX doJdoJio AmhoV.
Aem àH$maÀ¶m JQ>mVrb H$aUtZm {dOmVr¶ H$aUr (unlike surds>) Ago åhUVmV.
g§{jßV énmVrb doJdoJiçm H«$‘mÀ¶m qH$dm doJdoJir H$aUrnXo AgUmè¶m qH$dm XmoÝhr doJdoJio AgUmè¶mH$aUtÀ¶m JQ>mbm {dOmVr¶ H$aUr (unlike surds) Ago åhUVmV.
Imbrb CXmhaUm§Mm Aä¶mg H$am:1. 3 5+ XmoZ H$aUtMr ~oarO
2. 7 3- XmoZ H$aUtMr ~Om~mH$s
{Xboë¶m g§{jßV énmVrb H$aUrMm H$aUr H«$‘ Am{U H$aUrnX ¶m§Mr VwbZm H$am.
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× ×
3. 6 3 5+ EH$nXr H$aUr Am{U n[a‘o¶ g§»¶m ¶m§Mr ~oarO
4. 6 5+x y XmoZ H$aUtMr ~Om~mH$s
darb à˶oH$ CXmhaUm‘ܶo XmoZ H$aUtMr ~oarO qH$dm dOm~mH$s AWdm EH$nXr H$aUr d EH$ n[a‘o¶g§»¶m Amho. Aem àH$maÀ¶m H$aUtZm {ÛnXr H$aUr Ago åhUVmV. (binomial surds.)H$aUtMr ~oarO Am{U dOm~mH$s : (Addition and substraction of surds )
H$aUtMo gOmVr¶ d {dOmVr¶ H$aUr ¶m XmoZ àH$mamV dJuH$aU H$aVmV. ¶m XmoZ àH$maÀ¶m H$aUtgmR>r~oarO Am{U dOm~mH$s H$aUo e³¶ Amho H$m?
¶m àûZmMo CÎma XoʶmgmR>r gOmVr¶ Am{U {dOmVr¶ ~¡{OH$ nXm§Mr ~oarO Am{U dOm~mH$s AmR>dm.
Amåhmbm ‘m{hV Amho H$s ’$³V gOmVr¶ nXm§Mr ~oarO Am{U dOm~mH$s H$aVm ¶oVo, ˶mMà‘mUo ’$³VgOmVr¶ H$aUtMr ~oarO Am{U dOm~mH$s H$é eH$Vmo.
åhUOoM g§{jßV énmVrb Á¶m H$aUtMm H«$‘ d H$aUrnX gmaIo Amho ’$³V ˶m§MrM ~oarO Am{U dOm~mH$sH$é eH$Vmo.
åhUyZ H$aUtMr ~oarO d dOm~mH$s H$aʶmgmR>r H$aUtZm g§{jßV én XoD$Z ˶m§À¶m ghJwUH$m§Mr ~oarO qH$dmdOm~mH$s {dVaU {Z¶‘mMm Cn¶moJ H$éZ H$aVm ¶oVo.
gmoS>{dbobr CXmhaUo
CXmhaU 1 : 2 3 2 5 2+ + Mr qH$‘V H$mT>m.
CH$b: 2 3 2 5 2+ + (H$aUr g§{jßV énmV AmhoV.)(˶m gOmVr¶ H$aUr AmhoV)
= (1 + 3 + 5 ) ({dVaU JwUY‘m©Mm Cn¶moJ H$éZ)
=9 2
2 3 2 5 2+ + = 9 2
CXmhaU 2 : 4 63 5 7 8 28+ - gwb^én Úm.
CH$b: 4 63 5 7 8 28+ -
= 4 9 7 5 7 8 4 7+ - = 12 7 5 7 16 7+ -
= (12 + 5 – 16) 7 = 7 ({dVaU JwUY‘© dmnéZ)
= 4 63 5 7 8 28 7+ - =
CXmhaU 3 : gwb^ én Úm 3 3 3 32 16 81 128 192+ - +
CH$b : àW‘ H$aUr ˶mÀ¶m g§{jßV énmV ‘m§S>m
32 16 = 3 3 32 8 2 2 2 2 4 2= = 3 81 = 33 27 3 3 3 =× ×
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3 128 = 3 364 2 4 2 = 3 192 = 3 364 3 4 3 =3 3 3 32 16 81 128 192+ - + = 3 33 34 2 3 3 4 2 4 3+ - +
= 34 2 34 2- 3 33 3 4 3+ + (gOmVr¶ H$aUtMr ‘m§S>Ur H$éZ)
= (3 + 4) 3 3 = 37 33 3 3 32 16 81 128 192+ - + = 37 3
CXmhaU 4 : ( )4 6+x y Am{U ( )3 4 3-x y Mr ~oarO H$am.
CH$b: ( ) ( )4 6 3 4 3+ + -x y x y
= 4 6 12 9+ + -x y x y (H§$g gmoS>dyZ)
= 4 12 6 9+ + -x x y y (gOmVr¶ H$aUtMm JQ> H$éZ)
= (4 12) (6 9)+ + -x y (gOmVr¶ H$aUtMr ~oarO d dOm~mH$s)
= 16 3-x y
( ) ( )4 6 3 4 3+ + -x y x y = 16 3-x y
ñdmܶm¶ 7.1
I. Imbrb H$aUtZm gaién Úm. :
1. 75 108 192+ - 2. 4 12 50 7 48- -
3. 45 3 20 3 5- + 4. 2 2 3 8 2+ -a a a
5. 3 33 3 2 9+ -x x x x 6. 12 50 5 3 147 32+ + - -
7. 4 7 3 252 5 343- + 8.1 1 1 1
50 75 18 38 6 8 3
+ - -
II. Imbrb H$aUtMr ~oarO H$am.
1. ( ,2 ,4 )x y x y x y
2. 3 3 35 p, 3 p, 2 p
3. 3 3, , 3 , 4x x y y x y
4. ( 12 20), (3 3 2 5), ( 45 90)+ + -
5. ( 3 2), (2 2 3 3), (4 2 3 3)+ + -
6. ( 2 ), (2 3 ), (3 )+ - +x y x y x y
III. 1. 5 x ho 9 x ‘YyZ dOm H$am Am{U CÎma KmVm§H$ énmV {bhm.
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2. 3 p ho 10 p ‘YyZ dOm H$am.
3. 3 a ho 4 a d 2 a ¶m§À¶m ~oaOo‘YyZ dOm H$am.
4. 2 3+x y ho 5 -x y ‘YyZ dOm H$am.
H$aUtMm JwUmH$ma (Multiplication of surds )
Amåhr H$aUrMr ~oarO d dOm~mH$s Aä¶mgbobr Amho. ¶oWo AQ> Aer H$s$ g§{jßV énmVrb H$aUtMm H«$‘Am{U H$aUrnX gmaIo Agbo nm{hOo.
H$aUrMm JwUmH$ma H$aVmZm hrM AQ> bmJy nS>Vo H$m¶?
H$aUr KmVm§H$ énmV ‘m§S>Vm ¶oVmV ho Amåhr Aä¶mgbobo Amho. KmVm§H$mÀ¶m {Z¶‘mZwgma Amåhmbm ‘m{hVAmho H$s am × an = am + n . hm {Z¶‘ O|ìhm KmVm§H$mMm AmYmam§H$ gmaIm AgVmo. V|ìhm bmJy nS>Vmo. O|ìhmAmYmam§H$ gmaIm ZgVmo V|ìhm JwUmH$ma H$gm H$aUma?
CXm. :1na ×
1nb = ?
darb CXmhaU AmnU H$aUrénmV KmVm§H$m§Mm IV {Z¶‘mZo Ago {bhÿ eH$Vmo. = =n n n na b a ×× b ab
¶mdéZ AmnU Agm {ZîH$f© H$mTy> eH$Vmo H$s$, H$aUrMm JwUmH$ma H$aVmZm H$aUrMm H«$‘ gmaIm Agbmnm{hOo. H$aUr nX gmaIo qH$dm doJio Agy eH$Vo.
AmVm AmnU H$mhr H$aUrMm JwUmH$ma {eHy$¶m.
KQ>Zm 1: g‘mZ H«$‘mÀ¶m H$aUtMm JwUmH$ma
Imbrb CXmhaUm§Mo {ZarjU H$am.
CXmhaU 1 : gmoS>dm 5 3
CH$b: 5 3 = 5 3 = 15
CXm 2 : 57 JwUmH$ma H$am.
CH$b: 57 = 7 5 = 35
CXmhaU 3 : ( )3 5 6+ gaién Úm.
CH$b: ( )3 5 6+ = 3 5 3 6+ ({dVaU JwUY‘m©Mm Cn¶moJ H$éZ)
= 3 5 3 6+ =n n na b ab hm {Z¶‘ dmnéZ)
= 15 18 15 9 2 15 3 2+ = + = +
3( 5 6) 15 3 2+ = +
×
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CXmhaU 4 : 33 32 3 3 4 4 2 Mr qH$‘V H$mT>m.
CH$b: 33 32 3 3 4 4 2 (gmaIm H«$‘ )
= 32 3 4 3 4 2 n n n na b c abc hm {Z¶‘ dmnéZ )
= 3 3 3324 24 24 3 2 24 2 3= = = 348 3
33 332 3 3 4 4 2 48 3´ ´ =
nmhmb H$s darb gd© CXmhaUm‘ܶo H$aUtMm H«$‘ gmaIm Amho.
KQ>Zm 2 : {^ÝZ H«$‘mÀ¶m H$aUrMm JwUmH$ma
Oa H$aUr gma»¶mM H«$‘mÀ¶m ZgVrb Va Amåhr AJmoXaÀ¶m ^mJmV MMm© Ho$boë¶m JwUmH$mamÀ¶m nÜXVrMmdmna H$é eH$V Zmhr.
Va, AmVm {^ÝZ H«$‘mÀ¶m H$aUtMm JwUmH$ma H$gm H$am¶Mm? Imbrb CXmhaUo nmhm.
Imbrb CXmhaUo Aܶmgm
JwUmH$ma H$am 5 Am{U 3 2
H$aUrMm JwUmH$ma H$aVmZm, H$aUrMm H«$‘ gmaIm Agbm nm{hOo. ˶mgmR>r ¶m {Xboë¶m H$aUtMm H«$‘ gmaImH$éZ KoD$.
{Xboë¶m H$aUrMm H«$‘ H$gm gmaIm H$am¶Mm? H$aUrMm H«$‘ gmaIm H$aʶmÀ¶m Imbrb nm¶è¶m nhm.
nm¶ar 1 : {Xboë¶m H$aUr KmVm§H$ énmV ‘m§S>m ½ 1/335 2 5 2
¶m KmVm§H$ énmVrb {bhrboë¶m H$aUtMm KmVm§H$ hm n[a‘o¶ énmV Amho.
¶oWo KmVm§H$mVrb N>oX hm H$aUtMm H«$‘ Xe©{dVmo. åhUyZ Oa Amåhmbm H$aUtMm H«$‘ gmaIm H$am¶MmAgob Va n[a‘o¶ én ho g‘mB©H$ N>oXm‘ܶo énm§VarV H$é.
g‘mB©H$ N>oXm‘ܶo ho H$go ê$nm§VarV Ho$bo OmVo ?
AmVm {Xboë¶m H$aUrVrb H«$‘m§Mm b.gm.{d H$mT>ʶmMr nÜXV Amåhr AmR>dy. åhUyZ Amåhr H$aUtÀ¶mH«$‘mMm b.gm.{d. H$mTyZ gma»¶mM H$aUr H«$‘mV énm§Va H$é.
nm¶ar 2: 2 Am{U 3 Mm b.gm.{d. H$mT>m 2 Am{U 3 ¶m§Mm b.gm.{d 6 Amho.
nm¶ar 3:à˶oH$ KmVm§H$mZm b.gm.{d.Zo JwUyZ×
×
×125
63 16 32
62
6
gaiê$n Úm. ×× ×1 1
3 26 65 2
nm¶ar 4: naV H$aUrénmV ‘m§S>m ×6 63 25 2 = × 66125 4
nm¶ar 5: ´ =n n na b ab hm {Z¶‘ dmnam 66125 4 500=
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635 2 500´ =
{^ÝZ H$aUr H«$‘mMm H$aUtMm JwUmH$ma H$aVmZm dmnaë¶m OmUmè¶m nm¶è¶m :
1. {Xboë¶m H$aUtÀ¶m H«$‘mMm b.gm.{d. H$mT>m.
2. à˶oH$ H$aUr gma»¶mM H$aUr H«$‘mV ~Xbm.
3. ´ =n n na b ab ¶m {Z¶‘mMm Cn¶moJ H$éZ JwUmH$ma H$am.
gmoS>{dbobr CXmhaUo
CXmhaU 1 : 3 2 Am{U 4 3 ¶m§Mm JwUmH$ma H$am.
CH$b: 3 Am{U 4 ho doJdoJio H«$‘ AgyZ 3 Am{U 4 ¶m§Mm b.gm.{d. 12 Amho.
43 2 3 = 1 13 42 3 (H$aUrMo KmVm§H$ én)
=132
124 112 43
123
12 (à˶oH$ KmVm§H$mbm b.gm.{d. Zo JwUmH$ma d ^mJmH$ma H$am.)
=4 3
12 122 3 =
= 1212 4 32 3 (KmVm§H$ én H$aUr énmV nwÝhm {bhm.)
= 12 4 32 3 = 1216 27 ( =n n na b ab ¶m {Z¶‘mMm Cn¶moJ H$éZ)
= 12 432
1243 2 3 432=
darb XmoZ CXmhaUmdéZ Amåhr Agm {ZîH$f© H$mTy> eH$Vmo H$s XmoZ H$aUr Á¶m§Mm H«$‘ gmaIm Zmhr ˶m§MmH«$‘ gmaIm H$amdm bmJVmo. H«$‘ b.gm.{d. BVH$m H$amdm bmJVmo. hm H«$‘ H$aUtÀ¶m H«$‘m§Mm b.gm.{d.hmo¶.åhUOoM {Xboë¶m H$aUr XmoZ H$aU§rÀ¶m b.gm.{d. ê$nmV ‘m§S>VmV.
CXmhaU 2 : 3 Am{U 3 5 ¶m§Mm JwUmH$ma H$am.
CH$b: n¶m©¶r nÜXV :
H$aUrÀ¶m H«$‘mMm b.gm.{d. = 6
3 Am{U 3 5 Mm H«$‘ 6 énm§VarV H$am.
3 ¶m H$aUrÀ¶m H«$‘mbm åhUOoM 2, bm 3 Zo JwUm.
Oa ho Ho$bo Va H$m¶ AmR>dVo Vo nmhm.
2 3 63 3 3Þ = nU, 3 3¹ 63 3¹
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¶oWo Amåhr nmhVmo H$s H$aUrMr qH$‘V ~XbVo. Amåhmbm H$m¶ H$amdo bmJob H$s OoUoH$éZ ˶mMr nyduMrqH$‘V A~m{YV am{hb?
Imbrb à‘mUo nmhm.
32 3 33 3 3=1 12 3
123 3= = =
ho Ago gwM{dVo H$s Amåhr {Xboë¶m H$aUrÀ¶m ‘yi H«$‘mMm JwUmH$ma H$aUrMm H«$‘mVm ~XbVmZm H$aVmZm˶mMr ‘yi qH$‘V VerM R>odyZ H$aUr¶ nXm§Mm gmaImM KmVm§H$ KoVmo.
˶mMà‘mUo, 3 5 = 23 2 25 5=
1 13 2 1 335 5=
33 5 = 2 3 3 23 23 5
= 6 627 25 = 66 27 25 675= = 6 675
33 5 = 6 675
KQ>Zm 3: {ÛnXr H$aUm§Mm JwUmH$ma (Multiplication of Binomial surds)
CXmhaU 1: ( )6 2+ bm ( )6 2+ Zo JwUm.
CH$b: ( )6 2+ ( )6 2+
= ( )26 2+ ho (a+b)2 À¶m ñdê$nmV Amho.
= ( ) ( )2 26 2 6 2 2+ + (a+b)2 = a2 + 2ab + b2
= 6 +2 12 + 2
= 8 + 2 12
CXmhaU 2: ( )2 3x + bm ( )3 3x + Zo JwUm
CH$b ( ) ( )2 3 3 3x x+ + ho (x+a) (x+b) À¶m ñdê$nmV Amho.
= ( )2 2 3 3 3 2 3 3 3x x+ + + ´ (x+a) (x+b) = x2 + (a + b) x + ab
= x2 + 5 3 + 18
CXmhaU 3: ( ) ( )3 18 2 12 by 50 57+ - Zo JwUm
CH$b: ( ) ( )3 18 2 12 50 57+ -
= ( ) ( )9 2 4 3 5 2 3 3+ - à˶oH$ H$aUr ˶mÀ¶m g§{já énmV ~Xbm.
bm
×
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= 9 2 ( ) ( )5 2 3 3 +4 3 5 2 3 3- -
= 45 × 2 – 27 6 + 20 6 – (12 × 3)
= 90 – 7 6 36-
= 54 – 7 6
ñdmܶm¶ 7.2
I. gaiê$n Úm:
1. 3 7 2. 3 34 5 3. 4 44 6 4. 55 10 115. 66 2 5 6. n nx y 7. 8.
II. Imbrb H$aUtMm JwUmH$ma H$am.
1. 2 Am{U 3 4 2. 3 3 Am{U 4 2 3. Am{U 4. 3 Am{U 4 5
5. 5 Am{U 3 3 6. 3 4 Am{U 5 2 7. 3 5 Am{U 4 4 8. 3 2 Am{U 6 5
III. gwb^ê$n Úm.
1. ( ) ( )3 2 2 3 2 3 4 2+ - 2. ( ) ( )75 45 20 12- +
3. ( ) ( )3 2 3 2x y y x+ - 4. ( ) ( )6 5 6 5a b a b- +
5. ( ) ( )6 2 7 3 6 2 7 3- - 6. ( ) ( )3 27 5 9 3 7+ +
H$aUr {ZamgH$ Ad¶d Am{U H$aUr {ZamgH$ (Rationalising factor (R.F) and Rationalisation ofsurds)
Imbr {Xboë¶m gmaUr‘ܶo H$aUr, ˶m§Mm JwUmH$ma Am{U {ZH$mb {Xbobm Amho. ˶m§Mm Aä¶mg H$am.
A.Z§. H$aUr JwUmH$ma {ZH$mb
1. 7 , 7 7 × 7 = 7 n[a‘o¶ g§»¶m
2. 5 x , x 5 x x = 5x n[a‘o¶ g§»¶m
3. +x y , +x y +x y x y+ = +x y n[a‘o¶ g§»¶m
4. ab , ab ab ab = ab n[a‘o¶ g§»¶m
5. ( ) ( )6 3 5 6 3 5+ - ( )2 26 3 – 5 =108 – 25 = 83 n[a‘o¶ g§»¶m
6. ( ) ( )8 8x y x y+ - ( ) ( )2 28 – 64x y x y= - n[a‘o¶ g§»¶m
3 32 37 4 18 27 128
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darb gd© CXmhaUm‘ܶo XmoZ H$aUtMm JwUmH$ma hr n[a‘o¶ g§»¶m Amho.åhUyZ, 7 Mm H$maUr {ZamgH$ Ad¶d 7 Amho.
+x y Mm H$maUr {ZamgH$ Ad¶d +x y Amho.
( )6 3 5+ Mm H$aUr {ZamgH$ Ad¶d ( 6 3 5- ) Amho.
EH$m H$aUrbm Xþgè¶m H$aUrZo JwUbo AgVm n[a‘o¶ g§»¶m {‘iVo ¶m nÕVrbm H$aUr {ZamgH$ AgoåhUVmV.
Oa XmoZ {ÛnXr H$aUtMm JwUmH$ma hm n[a‘o¶ g§»¶m AgoV Va à˶oH$ H$aUr hr Xþgè¶m H$aUrbm H$aUr {ZamgH$Ad¶d åhUVmV. pìXnXr H$aUrÀ¶m H$aUr {ZamgH$ Ad¶dmbm AZw~ÜX H$aUr Agohr åhUVmV.
gmoS>{dbobr CXmhaUo
CXmhaU 1 : 3 2+ ¶m§Mr AZw~ÜX H$aUr ( 3 2- ) Amho ho nS>Vmim.
CH$b: 3 2+ = ( 3 2)( 3 2)+ -
= 2 2( 3) ( 2)- = 3 2 = 1 [(a + b) (a b) = a2 b2 {Z˶ g‘rH$aU dmnéZ]
( 3 2)+ Mr AZw~ÜX H$aUr ( 3 2)- Amho.
CXmhaU 2 : (5 3 )-x y Mm H$aUr {ZamgH$ H$mT>m.
CH$b: (5 3 )-x y = (5 3 )-x y ( )5 3+x y
= ( ) ( )2 25 3-x y ((a – b)(a + b) = a2 – b2 Mm Cn¶moJ H$éZ)
= 25x – 9y
( )25 3-x y bm ˶mÀ¶m AZw~ÜX H$aUrMm ( )5 3-x y Mm Cn¶moJ H$éZ H$aUr [Zamg Ho$bo Amho.
CXmhaU 3 : 3 5- + x ¶mMr AZw~ÜX H$aUr 3 5+ + x Amho ho nS>VmiyZ nhm.
CH$b: Oa ( )3 5- + x ¶mMr AZw~ÜX H$aUr ( )3 5+ + x Va ¶mMm JwUmH$ma n[a‘o¶ g§»¶m Agbrnm{hOo.
( )3 5- + x ( )3 5- + x = ( )223 5- + x = 9 – (5 + x) = 9 – 5 – x = 4 – x
(4 - x) hr n[a‘o¶ g§»¶m Amho.
( )3 5+ + x Mr AZw~ÜX H$aUr ( )3 5- + x Amho.
-
+
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- -
-
CXmhaU 4 :133 1
33- Mm H$aUr {ZamgH$ H$mT>m.
CH$b: g‘Om a =133 b = 1
33-
Va, a3 = ( )3133 = 3 Am{U b3 = ( )31
33- = 1 13
3- =
a3 - b3 =1 9 1 8
33 3 3
-- = =
nU a3 – b3 = (a – b)(a2 + ab + b2)
( ) ( ) ( )2 21 1 1 1 1 13 3 3 3 3 33 3 3 3 3 3- + + =
83
( )( )1 1 2 1 1 23 3 3 3 3 33 3 3 3 3- + ´ =
83
( )( )1 1 2 23 3 3 33 3 3 3 1- + + =
83
na§Vy83 n[a‘o¶ g§»¶m Amho, ( )1 1
3 33 3- Mm H$aUr {ZamgH$ Ad¶d ( )2 23 33 3 1- + hm Amho.
ñdmܶm¶ 7.3
I. Imbrb H$aUrMm H$aUr {ZamgH$ Ad¶d {bhm.
(1) a (2) 2 x (3) 7 y (4) xy (5) 4 +p q (6) 8 -x y (7)
1p
2 (8) a ab(9) x mn (10) 5p +a b
II. Imbrb {ÛnXr H$aUr|Mr AZw~ÜX H$aUr {bhm.
(1) +a b (2) 2-x y (3) 3 2-p q (4) 3+x y
(5) 10 2 3 5+ (6) 5 3+ (7) 8 5- (8) 3 7 7 3+
(9)1
22
+ (10)1 12 2
+x y (11) x a y b+ (12) xy z yz x+
III. Imbrb {ÛnXr H$aUrMm H$aUr {ZamgH$ Ad¶d emoYm.
(1)1 13 32 2
-+ (2)
1 13 35 5
-+ (3) 1 1+ - -y y
N>oXmMm H$aUr {Zamg H$éZ gaién XoUo. N>oXmMm H$aUr {Zamg H$aVmZm N>oXmÀ¶m {ZamgH$ Ad¶dmZo A§e Am{U N>oXmbm JwUmdo.
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gmoS>{dbobr CXmhaUo
CXmhaU 1 : CXm (1)35 ¶m N>oXmMm H$aUr {Zamg H$éZ gaién Úm.
CH$b:35 =
35 5 Mm {ZamgH$ Ad¶d 5 Amho.
35 =
3 55 5
´ (A§e Am{U NoXmbm N>oXmÀ¶m AZw~ÜX H$aUr> Zo JwUm)
=3 55 5
´´ =
155
CXmhaU 2 :68 N>oXmMm H$aUr {Zamg H$éZ gai én Úm.
CH$b:6 88 8
=6 8 6 4 2 12
8 8= =
32
8 2
322
=
6 88 8
´6 3 2
28=
CXmhaU 3 :bca N>oXmMm H$aUr {Zamg H$éZ gai én Úm.
CH$b:bca =
bca ×
aa
( a Mm H$aUr {ZamgH$ a Amho.)
=bc a
a =
abca
bca
abca
CXmhaU 4 :3
5 3- N>oXmMm H$aUr {Zamg H$éZ gai én Úm.
CH$b:3
5 3- 5 3- hm NoX Amho.>
5 3- Mm H$aUr {ZamgH$ 5 3+ Amho.
35 3- =
3 5 35 3 5 3
+- +
=( )
( ) ( )2 2
3 5 3
5 3
+
- =
( ) ( )3 5 3 3 5 35 3 2
+ +=
-
×
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35 3- =
( )3 5 32+
CXmhaU 5 :6 36 3
+-
N> oXmMm H$aUr {Zamg H$éZ gai én Úm.
CH$b:6 36 3
+- 6 3- Mr AZw~ÜX H$aUr 6 3+ Amho.
=6 3 6 36 3 6 3
+ +- +
=( )
( ) ( )
2
2 2
6 3
6 3
+
-( (a – b) (a + b) = a2 – b2 dmnéZ)
=( ) ( )2 2
6 3 2 6 36 3
+ +-
(a + b)2 = a2 + 2ab + b2) dmnéZ]
=6 3 2 18 9 6 2 3
3 3+ + +
= =( )3 2 2
3+
= 3 2 2+
6 33 2 2
6 3+
= ++
CXmhaU 6 :5 3
5 2 5 2-
+ -gaiê$n Úm.
CH$b:5 3
5 2 5 2-
+ -
5 2+ H$aUr {ZamgH$ 5 2- Am{U 5 2- H$aUr {ZamgH$ 5 2+ Amho.
5 35 2 5 2
-+ -
=5 5 2 3 5 2
5 2 5 2 5 2 5 2- +
-+ - - +
(A§e Am{U N>oXmbm ˶m§À¶m
H$aUr {ZamgH$mZo)
=( )
( )( )
( )2 22 2
5 5 2 3 5 2
5 2 5 2
- +-
- -
=( )5 2 5 15 2 3
5 4 5 4- +
-- -
= 5 2 5 15 2 3- - -
5 35 2 5 2
-+ -
= 5 2 5 15 2 3- - -
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159
CXmhaU 7 :1 1
4 483 2
+ gai ê$n Úm.
CHb$:1 1
4 483 2
+ =4 48 4 4 3
2 23 3+ = + 3 Mm H$aUr {ZamgH$ 3 Amho.
4 4 323
+ =4 3 4 3
23 3´ + =
4 3 4 33 2
+
8 3 12 36
+= =
2010
36 3
=10 3
31 1 10 3
4 483 2 3
+ =
gmoS>{dbobr CXmhaUo 7.4
I. N>oXmMm H$aUr {Zamg H$éZ gaién Úm.
A. (1)83 (2)
32 x (3)
52y (4)
1 22 5
a
B. (1)2
3 2+ (2) -x
x y (3)10
5 3+(4)
3 56 3-
(5)-ab
a b
C. (1)3 23 2
+-
(2)5 2 33 2 5
--
(3)4 3 2
3 2+
+(4)
3 63 6+
+
II. gaién Úm.
(1)2 5
3 2 3 2+
- + (2)5 3
5 3 5 3-
- +
(3)6 25 5 2
++
(4)7 3 2 56 3 8 2
-- +
(5)21 2 5
3 7 21 5+
+ +(6) Oa x = 2 6 5+ Va
1+x
x H$mT>m.
III. x Mr qH$‘V H$mT>m. 1) 3x-23 +2x
=2+3x - 42
2) x-1x +1
=4+x - 1
2
3 56
(5)
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160
a
H$aUr
H$aUrMm AW© H$aUrnX a H$aUrdarb {H«$¶m H$aUr {ZamgH$
H$aUtMo àH$ma H$aUrMm H«$‘ n H$aUtMr ~oarO {ZamgH$ Ad¶d
gOmVr¶ H$aUr H$aUtMr dOm~mH$s {ÛnXrH$aUtMr
{dOmVr¶ H$aUr H$aUtMm JwUmH$maAZw~Õ H$aUr
{Û‘mZ H$aUr gmaImM H«$‘ doJdoJimH«$‘ N>oXmMm/A§emMm H$aUr {Zamg H$ê$Z gai ê$n XoUo
n a
CÎmao
ñdmܶm¶ 7.1
I. (1) 3 3 (2) 5( 2 4 3 )- - (3) 0 (4) 7 2a (5) 0
(6) 2 (7) 21 7 (8)2 34 2
+
II. (1) 7x y (2) 310 P (3) 4 5x x y y+ (4) 5 3 7 5 3 10+ -
(5) 3 7 2+ (6) 6 x
III. (1) ( )124 x (2) 7 P (3) 3 a (4) 3 4x y-
ñdmܶm¶ 7.2
I. (1) 21 (2) 3 20 (3) 4 24 (4) 5 110
(5) 610 (6) n xy (7) 36 28 (8) 144 3
II. (1) 6 128 (2) 12 648 (3) 12 200 (4) 4 45
(5) 6 1125 (6) 15 8192 (7) 12 40,000 (8) 6 20
III. (1) 6 + 6)–2( (2) 4 15 (3) 5 6 6xy x y- + (4) 36a – 25b
(5) 219 – 84 6 (6) 278 + 108 3
ñdmܶm¶ 7.3
I. (a) a (b) x (c) y (d) xy (e) p q+
(f) x y- (g) p (h) ab (i) mn (j) a b+
II. (a) a b- (b) 2x y+ (c) 3 2p q+ (d) 3x y- (e) 10 32 5-(f) 5 3- (g) 8 5+ (h) 3 7 7 3- (i)
12
2- (j)
1 12 2
x y-
(k) x a y b- (l) xy z yz x-
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III. (a)2 23 3[2 2 1]-
+ - (b)2 23 3[5 [
1 5-- - (c) 1 1y y+ + -
ñdmܶm¶ 7.4
I. A. 5)4)33
81) 3) 102y
y 1010
a 302
32xx2) B.1) 2)
))
))x y-2 3 - 2 x x y+
a-b
) ) )3) 5)4)52
2 - 5 ab6+ a+30 C. 1510-31) 2)5+213
6 -6 30 + 5
)
4)2 - 2 63) 10-3 116
-
II. 30+10
) )31015 -5 -1) 2) 3)2+ 15
6 +2
4 ))
4)3
21 2 + 1 10-6) 10III. 1) 12 2) 81
***********
*******
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~hþnXr
* ~hþnXrM H$moQ>r
* ~hþnXrMo ewݶ
* ~hþnXrMr ^mJmH$ma H$m¶m©dbr(Algorithm)
* eof {gÜXm§V
* Ad¶d {gÜXm§V
* g§íbofH$ ^mJmH$ma
8
Paolo Ruffin(1765-1822, Italy)
An elegant way of dividing apolynomial by a l inearpolynomial was introduced byPaolo Ruffin in 1809. Hismethod is known as Syntheticdivision, which facilitates thedivision of a polynomial by alinear polynomial or binomialof the form (x-a) with the helpof the co-efficients involved.
[Polynomials]
¶m KQ>H$mÀ¶m Aä¶mgmZ§Va ho gwb^ hmoB©b.
* ~hþnXrMr H$moQ>r AmoiIUo.
* ~hþnXrMo ewݶ emoYUo.
* ~hþnXrMo ^mJmH$ma H$m¶m©dbr ñnï> H$aUo.
* ^mÁ¶, ^mOH$, ^mJmH$ma, ~mH$s emoYʶmgmR>r
^mJmH$ma H$m¶m©dbrMm Cn¶moJ H$aUo.
* eof {gÜXm§V ñnï> H$aUo.
* Ad¶d {gÜXm§V ñnï> H$aUo.
* ^mJmH$ma Z H$aVm eof {gÜXm§MmMm Cn¶moJ H$éZ ~mH$s emoYUo.
* Ad¶d {gÜXm§VmMm Cn¶moJ H$éZ, {Xbobr ~hþnXr, Xþgè¶m ~hþnXrMm Ad¶d Amho H$m, Vo VnmgUo.
* ^mJmH$ma Am{U ~mH$s emoYʶmgmR>r g§íbofH$ ^mJmH$ma nÜXVrMm Cn¶moJ H$aUo.
~rOJ{UV ho Ago ~m¡pÜXH$ gmYZ Amho Á¶mMr {Z{‘©VrOJmVrb n[a‘mUdmMH$ Ñï>rH$moZmMo g‘W©Z H$aʶmgmR>rPmbr Amho.
-Aë’«o$S> Zm°W© ìhmB©Q>hoS>
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Polynomials 163
Vw‘À¶m ‘mJrb dJm©‘ܶo Vwåhr ~hþnXr Am{U ˶mdarb {H«$¶m ¶m§Mm Aä¶mg Ho$bobm Amho. ˶mMr AmR>dU H$éZCOiUr H$é. 'x ' ho MbnX, 'n' hm YZ nyUmªH$ Am{U a1, a2, a3.....an hr pñWa nXo (dmñVd g§»¶m).Va, p(x) = a0 + a1x + a2x2 + a3x3 + ....... + anxn, ¶m Z‘wݶmVrb ~¡{OH$ amer Á¶m‘ܶo MbnXmMmKmVm§H$ ’$º$ YZ nyUmªH$ Agob Va ˶m ~¡{OH$ amerbm x ‘Yrb ~hþnXr Ago åhUVmVbjmV ¿¶m H$s, x
0 1 22 ........ n
np(x) x + aa + a ax + + ~hþnXr‘ܶo
* an 0* a0, a1x1, a2x2, a3x3......anxn ¶m§Zm ~hþnXrMr nXo åhUVmV.* a0, a1, a2 .......an – 1, an ho AZwH«$‘o x0, x1, x2,......xn – 1, xn ¶m§Mo ghJwUH$ AmhoV.
CXmhaUmW©,p(x) = 4x – 3 hr x. ‘Yrb ~hþnXr Amho.g(y) = 2y2 + 3y – 10 hr y ‘Yrb ~hþnXr Amho.
f(u) =14
u3 + 6u2 + u + 8 hr u ‘Yrb ~hþnXr Amho.
Imbrb ~¡{OH$ ametMo {ZarjU H$am.
* 3x2 –2 5x * x3 – 2x2 + 3 x + 10 * 2
14 6x x
¶m ~hþnXr AmhoV H$m ? H$maU gm§Jm.~hþnXrMr H$moQ>r : (Degree of a Ploynomial)
Imbrb H$moï>H$mV {Xboë¶m ~hþnXr, ˶m§Mo MbnX Am{U KmVm§H$mMo {ZarjU H$am.~hþnXr MbnX ‘moR>çmV ‘moR>m KmVm§H$5x + 4 x 13y2 + 4y + 1 y 2
3 21 5 63
m m m m 3
2u4 + u3 – 2u + 8 u 4
* ~hþnXr‘Yrb MbnXmÀ¶m ‘moR>çmV ‘moR>çm KmVm§H$mbm ˶m ~hþnXrMr H$moQ>r Ago åhUVmV.~hþnXr p(x) = 5x + 4 Mr H$moQ>r 1 Amho.~hþnXr p(y) = 3y2 + 4y + 1 Mr H$moQ>r 2 Amho.
~hþnXr p(y) = 3 21 5 63
m m m Mr H$moQ>r 3 Amho.
~hþnXr p(y) = 2u4 + u3 – 2u + 8 Mr H$moQ>r 4 Amho.
CXmhaUmW©,
p(y) = 3y2 + y – 6 ¶m y ‘Yrb ~hþnXrMr H$moQ>r 2 Amho.
p(x) = 7x2 + x – 6 ¶m x ‘Yrb ~hþnXrMr H$moQ>r 2 Amho.
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Polynomials 164
pñWa ~hþnXr (Constant Polynomial)Imbr {Xboë¶m ~hþnXtMo {ZarjU H$am.
f(x) = 10 p(x) = – 2 g(x) =17
h(y) =34
¶mZm pñWa ~hþnXr Ago åhUVmV.
pñWa ~hþnXr 0 qH$dm f(x) = 0 bm ewݶ ~hþnXr Ago åhUVmV.
~hþnXtMo àH$ma [Types of Polynomials]AmVm AmnU doJdoJù¶m H$moQ>tÀ¶m ~hþnXr Am{U ˶m§À¶m Zmdm§Mm {dMma H$é.
Imbrb gmaUrMm Aä¶mg H$am.
~hþnXr H$ m oQ >r gm‘mݶ Z‘wZm CXmhaU o
aofr¶ ~hþnXr 1 ax + b 4x + 5OoWo a 0 3y + ½
dJ© ~hþnXr 2 ax2 + bx + c 2x2 – 6x + 5
OoWo a 0 2 13 42
x x
KZ ~hþnXr 3 ax3 + bx2 + cx + d x3 + 2x2 – 4x + 7
OoWo a 0 3 12 83
x x
darb gd© KQ>Zm‘ܶo a, b, c, d, e.... dmñVd g§»¶m qH$dm dmñVd ghJwUH$ AmhoV.
~hþnXtMr qH$‘V [Value of a Polynomial]
CXmhaU 1 : f(x) = 4x + 5. ¶m aofr¶ ~hþnXrMm {dMma H$é. Oa x = 1, Va ~hþnXr f(x) Mr qH$‘V H$m¶?
CH$b: ~hþnXr f(x) ‘ܶo x Mr qH$‘V dmnê$Z gmoS>dm. f(x) = 4(x) + 5f(1) = 4(1) + 5 = 4 + 5 = 9
f(x) = 9 Ooìhm x = 1
f(x) = 4(x) + 5 Mr qH$‘V 9 Amho, Ooìhm x = 1.
CXmhaU 2 : dJ© ~hþnXr g(y) = y2 + 3y + 5. Mm {dMma H$é. ~hþnXr g(y),Mr qH$‘V {H$Vr? Ooìhmy = 2.
CH$b : g(y) = y2 + 3y + 5
g(2) = (2)2 + 3(2) + 5 = 4 + 6 + 5 = 15
g(y) = y2 + 3y + 5 Mr qH$‘V 15 Amho, Ooìhm y = 2.
{dMma H$am! ewݶ ~hþnXrÀ¶m H$moQ>rMr
ì¶m»¶m H$aVm ¶oV Zmhr.
H$m ?
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Polynomials 165
darb CXmhaUmnmgyZ Amåhr {ZîH$f© H$mTy> eH$Vmo H$s,
Oa f(x) hr 'x' ‘Yrb ~hþnXr Am{U 'k' hr dmñVd g§»¶m AgyZ, f(x) ‘ܶo 'x' À¶m EodOr 'k'
KodyZ {‘iUmè¶m dmñVd g§»¶obm f(x), Mr qH$‘V Ago åhUVmV. Am{U ho f(k) Ago Xe©{dVmV.
KZr¶ ~hþnXrMr {H$‘V :
f(x) = x3 + 2x2 – 3x + 4 ¶m KZ ~hþnXrMr qH$‘V, x = 1 Am{U x = – 1 AgVmZm Imbrbà‘mUo Amho,
f(1) = 13 + 2(1)2 – 3(1) + 4 = 1 + 2 – 3 + 4 = 4
f(–1) = (–1)3 + 2(–1)2 – 3(–1) + 4 = –1 + 2 + 3 + 4 = 8
~hþnXrMo ewݶ (Zero of a polynomial)
AmVm AmnU H$m§hr ~hþnXr KodyZ Xe©{dë¶mà‘mUo ˶m§Mr qH$‘V H$mTy>.
CXmhaU 1 : f(x)= x2 – x – 2 OoWo x = 2
f(2)= 22 – 2 – 2 = 4 – 4 = 0 f(2) = 0
MbnXmÀ¶m {Xboë¶m {H$§‘VrgmR>r darb gd© CXmhaUm‘ܶo ~hþnXrMr qH$‘V ~amo~a 0 (ewݶ) Amho.
MbnXmÀ¶m ¶m qH$‘Vrbm "~hþnXrMo ewݶo' Ago åhUVmV.
2 ho f(x) = x2 – x – 2 ¶m ~hþnXrMo ewݶ Amho.
– 1 ho p(x) = x2 – 3x – 4 ¶m ~hþnXrMo ewݶ Amho.
darb MM}VyZ Amåhr Agm {ZîH$f© H$mTy> eH$Vmo H$s, Oa p(x) hr ~hþnXr Am{U k hr H$moUVrhr dmñVd
g§»¶m Aer Amho H$s, p(k) = o, Va k bm ~hþnXr p(x) Mo ewݶ Ago åhUVmV.
CXmhaUmW© :
f(x) = x2 - 5x + 6 ¶m ~hþnXrMr ewݶo 2 Am{U 3 AmhoV.H$maU f(2) = 0 Am{U f (3) = 0.
H¥$Vr : H$m§hr aofr¶, dJ© Am{U KZ~hþnXtMm {dMma H$am. ˶m ~hþnXtMo ewݶ emoYm. Imbrb {dYmZo nS>VmiyZ
nmhm.
1. aofr¶ ~hþnXrbm OmñVrV OmñV EH$ ewݶo AgVmo.
2. dJ© ~hþnXrbm OmñVrV OmñV XmoZ ewݶo AgVmV.
3. KZ ~hþnXrbm OmñVrV OmñV VrZ ewݶo AgVmV.
gm‘mݶnUo 'n' H$moQ>rÀ¶m ~hþnXrbm OmñVrV OmñV 'n' ewݶo AgVmV.
CXmhaU 2 : p(x)= x2 – 3x – 4 OoWo x = – 1
p(–1)= (–1)2 – 3(–1) – 4 = 1 + 3 – 4 = 0 p(–1) = 0
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Polynomials 166
ho OmUyZ ¿¶m !^m¡{‘{VH$ÑîQ>çm H$moU˶mhr ~hþnXrMm ewݶ åhUOo Ogm ~hþnXrMm AmboI Am{U x - Aj EH$‘oH$mg N>oXVAgVrb Va ˶m§À¶m N>oXZ q~XþMm x - gh{ZX}eH$ hmo¶.
{dMma H$am !
~hþnXrMo H$moUVohr ewݶ gd© dmñVd g§»¶m‘YyZ AgboM Ago Zmhr.
CXmhaU, p(x) = x2 + 1 ¶m ~hþnXrMo ewݶo dmñVd g§»¶m n¡H$s Zmhr. åhUOoM k ho dmñVd Zmhr Ogo H$s
p(k) = 0. H$m ?
gmoS>{dbobr CXmhaUo
CXmhaU 1 : x 2 + 14x + 48 ¶m dJ© ~hþnXrMo ewݶ emoYm. Am{U nS>VmiyZ nmhm.
CH$b : {Xbobr ~hþnXr x 2 + 14x + 48.
dJ© ~hþnXrMo Ad¶d nmSy>Z,Amåhmbm {‘iob.
x2 + 14x + 48 = (x + 8) (x + 6)
åhUOoM x2 + 14 x + 48 Mr {H$‘§V eyݶ Ooìhm x + 8 = 0 qH$dm x + 6 =0
ho Ooìhm x = -8 qH$dm x=-6
x2 + 14x + 48 ¶m ~hþnXrMo ewݶo -8 d -6 AmhoV.
AmVm AmnU ~hþnXr‘ܶo {H$§‘Vr dmnê$Z nS>VmiyZ nmhÿ.
p(x) = x 2 + 14x + 48=(8)2+14-(-8)+48=64-112+48=0 p( 8) = 0
p( 6) = (-6)2+14 (-6)+48=36-84+48 p( 6)
XI X
YI
Y
O 1 2 3 4–1–2
–2
–3
–1
5
4
3
1
2
–3–4
y = +1x2
(0,1)
y = -5+6x x2
XI X
YI
Y
O 1 2 3 4–1–2
–2
–3
–1
5
4
3
1
2
–3–4(3, 0)(2, 0)
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Polynomials 167
CXmhaU 2. x 2 - 3 ¶m ~hþnXrMo ewݶo emoYm Am{U nS>VmiyZ nmhm.
CH$b : p(x) = x 2 – 3
x 2 – 3 Mo Ad¶d nmSy>Z x 2 – 3 = x2 – ( 3 )2 = (x + 3 ) (x – 3 )
(x 2 – 3) Mr qH$‘V ewݶo Amho Oa x = 3 qH$dm x = – 3
(x 2 – 3) Mo ewݶo 3 Am{U (– 3 ) AmhoV.nS>Vmim :
(x 2 – 3) Mo ewݶo 3 Am{U – 3 AmhoV.p(x) = x2 – 3p( 3 ) = ( 3 )2 – 3 = 3 – 3 = 0
VgoM p(– 3 ) = (– 3 )2 – 3 = 3 – 3 = 0
CXmhaU g§J«h 8.1
1. Imbrb ~hþnXtMr H$moQ>r (KmVm§H$) emoYm.(i) x2 – 9x + 20 (ii) 2x + 4 + 6x2
(iii) x3 + 2x2 – 5x – 6 (iv) x3 + 17x – 21 – x2 (v) 3 x3 + 19x + 14
2. Oa f(x) = 2x3 + 3x2 – 11x + 6, Va emoYm.(i) f(0) (ii) f(1) (iii) f(–1) (iv) f(2) (v) f(–3)
3. Imbrb ~hþnXtMr qH$‘V H$mT>m.(i) g(x) = 7x2 + 2x + 14, Ooìhm x = 1 (ii) p(x) = – x3 + x2 – 6x + 5, Ooìhm x = 2
(iii) p(x) = 2x2 +14
x + 13, Ooìhm x = – 1
(iv) (px) = 2x4 – 3x3 – 3x2 + 6x – 2, Ooìhm x = – 2
4. Imbr Xe©{dboë¶m g§»¶m {Xboë¶m ~hþnXtMo ewݶo AmhoV H$m? Vnmgm.
(i) f(x) = 3x + 1, x = –13
(ii) p(x) = x2 – 4, x = 2, x = –2
(iii) g(x) = 5x – 8, x =45
(iv) p(x) = 3x3 – 5x2 – 11x – 3, x = 3, x = –1 Am{U x = –13
5. Imbrb dJ© ~hþnXtMo ewݶ emoYm. A{U nS>VmiyZ nmhm.
(i) x2 + 4x + 4 (ii) x2 – 2x – 15 (iii) 4a2 – 49 (vi)2a2 – 2 2 a+ 1
6. Oa x = 1 ho f(x) = x3 – 2x2 + 4x + k, ¶m ~hþnXrMo ewݶo Agob Va k Mr qH$‘V emoYm.
7. k À¶m H$moU˶m qH$‘Vrg –4 ho x2 – x – (2k + 2) ¶m ~hþnXrMo ewݶ hmoB©b?
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Polynomials 168
~hþnXrgmR>r ^mJmH$ma H$m¶m©dbr [Division algorithm for polynomials]
Vwåhr ‘mJrb dJm©‘ܶo EH$m ~hþnXrbm Xþgè¶m ~hþnXrZo, [XK© ^mJmH$ma nÜXVrZo ^mJUo ho {eH$bmAmhmV.AmVmAmnU ˶m nÜXVrMr COiUr H$é.
CXmhaU 1 : (5x + x2 + 14 + 2x3) bm (x + 2) Zo ^mJm.
nm¶ar 0 :
¶m CXmhaUm‘ܶo ^mÁ¶ p(x) = 2x3 + x2 + 5x + 14
^mOH$ g(x) = x + 2
^mJmH$ma q(x) = 2x2 – 3x + 11
~mH$s r(x) = – 8
darb gd© CXmhaUm‘ܶo, Ooìhm ~hþnXr p(x) bm Xþgar ~hþnXr g(x), Zo ^mJbo OmVo Voìhm ^mJmH$ma q(x)
Am{U ~mH$s r(x). Imbrb gmaUrV 3 CXmhaUmMr g{dñVa ‘m{hVr {Xbr Amho.
CXmhaU ^mÁ¶ ^mOH$ ^mJmH$ma ~mH$sp(x) g(x) q(x) r(x)
1. 2x3 + x2 + 5x + 14 x + 2 2x2 – 3x + 11 –8
2. 9x4 – 4x2 + 4 3x2 + x – 1 3x2 – x –x + 4
3. 3x4 + 5x3 – 7x2 + 2x + 2 x2 + 3x + 1 3x2 – 4x + 2 0
^mÁ¶, ^mOH$, ^mJmH$ma Am{U ~mH$s ¶m‘Yrb ñnï> g§~§Ym~Ôb Amåhr ¶mnyduM {eH$bmo AmhmoV..
¶wp³bS>À¶m ^mJmH$ma {gÜXm§VmZwgma, (boå‘mZwgma)
^mÁ¶= ^mOH$ × ^mJmH$ma + ~mH$s
åhUOoM , Oa a Am{U b ho H$moUVohr XmoZ nyUmªH$ AgVrb Va, a = bq + r,
OoWo 0 r b.
hm g§~§Y ~hþnXtÀ¶m ^mJmH$mamgmR>r gwÜXm bmJy nS>Vmo.
åhUOoM ~hþnXr p(x) bm Xþgar ~hþnXr g(x), Zo ^mJë¶mg ¶oUmam ^mJmH$ma q(x) d ~mH$s r(x), Agob,
Va p(x) = g(x) × q(x) + r(x), OoWo g(x) ~amo~a ewݶ Zmhr. Am{U r(x) ~amo~a ewݶ qH$dm r(x) Mr H$moQ>rg(x) À¶m H$moQ>rnojm bhmZ Agob.
2
23
3
2
2
4
4
5
56
8
3
33
11
1111
14
1422
22
2
x
xx
x
xx
x
x
xx
xx
x-
-
-
-
(+) (+)
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Polynomials 169
hr H$m¶m©dbr ¶wp³bS>À¶m ^mJmH$ma {gÜXm§Vmbm g‘én AgyZ ¶mbmM "~hþnXtMr ^mJmH$ma H$m¶m©dbr'Ago åhUVmV.
~hþnXtÀ¶m ^mJmH$ma H$m¶m ©dbrZwgma,
Oa p(x) Am{U g(x) ¶m H$moU˶mhr XmoZ ~hþnXr AgyZ g(x) 0, Agob Va Amåhr q(x)Am{U r(x) ¶m ~hþnXr AemàH$mao emoYy eH$Vmo H$s,
p(x) = g(x) × q(x) + r(x), OoWo r(x) = 0 qH$dm r(x) Mr H$moQ>r g(x).À¶m H$moQ>r.nojm bhmZAmh o.
¶mbmM "¶wp³bS>Mm ~hþnXrgmR>r {gÜXm §V' Agohr åhUVmV.
AmVm AmnU MMm© Ho$boë¶m darb gmaUrVrb VrZ CXmhaUmgmR>r "~hþnXr§Mr ^mJmH$ma H$m¶m©dbr'nS>VmiyZ nmhÿ¶m.
CXmhaU 1 : 5x + x2 + 14 + 2x3 bm x + 2 Zo ^mJm.
CH$b : {XK© ^mJmH$mamZ§Va Amåhmbm {‘iVo
^mJmH$ma q(x) = 2x2 – 3x + 11 Am{U
~mH$s r(x) = – 8
~hþnXtÀ¶m ^mJmH$ma H$m¶m©dbrZwgma,
p(x) = g(x) × q(x) + r(x)
AmVm AmnU g‘rH$aUmMr COdr ~mOy Kody.
g(x) × q(x) + r(x)
^mOH$ × ^mJmH$ma + ~mH$s
(x + 2) (2x2 – 3x + 11) + (–8)
2x3 – 3x2 + 11x + 4x2 – 6x + 22 – 8
2x3 + x2 + 5x + 14 = ^mÁ¶
^mJmH$ma H$m¶m©dbr bmJy nS>Vo. (pgÜX hmoVo)
CXmhaU 2 : 9x4 – 4x2 + 4 bm 3x2 + x – 1 Zo ^mJm.
CH$b: ¶m CXmhaUm‘ܶo,
^mÁ¶ p (x) = 9x4 – 4x2 + 4, ^mOH$ g (x) = 3x2 – x -1
^mJmH$ma q (x) = 3x2 – x , ~mH$s r(x) = – x + 4
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Polynomials 170
~hþnXtÀ¶m ^mJmH$ma H$m¶m©dbrZwgma,
p(x)= g(x) × q(x) + r(x)
RHS= g(x) × q(x) + r(x)
= (3x2 + x – 1)(3x2 – x) + (–x + 4)
= 4 39 3x x 2 33 3x x 2x x x 4
= 9x4 – 4x2 + 4 = ^mÁ¶
^mJmH$ma H$m¶m©dbr bmJy nS>Vo. ({gÜX hmoVo)
[Q>n : AemM àH$mao {Vgè¶m CXmhaUmgmR>r ^mJmH$ma H$m¶m©dbr nS>VmiyZ nmhm.
Vwåhmbm ~hþnXtMm ^mJmH$ma ‘m{hV Amho. VgoM H$moU˶mhr XmoZ {Xboë¶m ~hþnXr ^mÁ¶ d ^mOH$ XrK©^mJmH$ma nÜXVrZo ^mJmH$ma d ~mH$s H$mTy> eH$Vm. ^mJmH$ma H$m¶m©dbrMm Cn¶moJ H$éZ ¶oUmam n[aUm‘ nS>VmiyeH$Vm. ¶m{R>H$mUr ‘hËdmMm Agm àíZ {Z‘m©U hmoVmo H$s,
^mJmH$ma Am{U ~mH$s {Xë¶mg ^mÁ¶ Am{U ^mOH$ emoYUo e³¶ Amho H$m?
hmo¶, ""~hþnXtMr ^mJmH$ma H$m¶m©dbr dmnéZ Amåhr ^mÁ¶ d ^mOH$ emoYy eH$Vmo.''
AmVm, Amåhr ^mJmH$ma H$m¶m©dbrMm Cn¶moJ ñnï> H$aʶmg H$mhr CXmhaUo Kody¶m.
(i) ^mJmH$ma H$m¶m©dbrMm Cn¶moJ H$éZ ^mÁ¶ d ^mOH$ emoYUo.
CXmhaU 3 : 3x3 + x2 + 2x + 5 bm ~hþnXr g(x), Zo mJë¶mg ¶oUmam mJmH$ma d ~mH$s AZwH«$‘o (3x – 5) Am{U(9x + 10) Amho Va g(x) emoYm.
CH$b : p(x) = g(x) × q(x) + r(x) [~hþnXtMr ^mJmH$ma H$m¶m©dbr]
Amåhmbm g(x). emoYm¶Mo Amho. åhUyZ darb g‘rH$aU nwÝhm {bhÿ¶m.
g(x) × q(x) + r(x) = p(x) ~mOy ~XbyZ
g(x) × q(x)= p(x) – r(x)
g(x) =( ) ( )
( )p x r x
q x =3 2(3 2 5) (9 10)
3 5x x x x
x
=3 23 2 5 9 10
3 5x x x x
x
g(x) =3 23 7 5
3 5x x x
x
AmVm g(x) [XK© ^mJmH$ma nÜXVrZo emoYy.
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Polynomials 171
2
2 3
2 13 5 3
x xx x 2
37 5
3x x
x 2
( ) ( )
2
5
6
x
x2
76x
( ) ( )10
3
x
x
( )
53x
( )5
0
g(x) = x2 + 2x + 1
^mOH$ x2 + 2x + 1hm Amho.
CXmhaU 2: ~hþnXr p(x) bm (2x – 1). Zo ^mJbo. ^mJmH$ma Am{U ~mH$s AZwH«$‘o (7x2 + x + 5) Am{U 4 AmhoV.Va p(x). emoYm.CH$b : p(x) = g(x) × q(x) + r(x) [~hþnXtMr ^mJmH$ma H$m¶m©dbr]
p(x) = (2x – 1)(7x2 + x + 5) + 4
p(x) = 14x3 + 2x2 + 10x – 7x2 – x – 5 + 4
p(x) = 14x3 – 5x2 – 9x – 1
^mÁ¶ p(x) = 14x3 – 5x2 – 9x – 1
(ii) à˶j ^mJmH$ma Z H$aVm ^mJmH$ma H$m¶m©dbrMm Cn¶moJ H$éZ ^mJmH$ma d ~mH$s emoYUo.
CXmhaU 3 : p(x) = x3 – 6x2 + 15x – 8 bm g(x) = x – 2 Zo ^mJ XodyZ ^mJmH$ma d ~mH$s emoYm.
CH$b : p(x) = x3 – 6x2 + 15x – 8 p(x) Mr H$moQ>r 3 Amho.
g(x) = x – 2 g(x) Mr H$moQ>r 1Amho.
^mJmH$ma q(x) Mr H$moQ>r = 3 – 1 = 2 ~mH$s r(x) Mr H$moQ>r ewݶ Amho.
AmVm q(x) = ax2 + bx + c (2 H$moQ>tMr ~hþnXr)
r(x) = k (pñWa ~hþnXr)
^mJmH$ma H$m¶m©dbrMm Cn¶moJ H$éZ,p(x) = g(x) × q(x) + r(x)
x3 – 6x2 + 15x – 8 = (x – 2)(ax2 + bx + c) + k= ax3 + bx2 + cx – 2ax2 – 2bx – 2c + k
x3 – 6x2 + 15x – 8 = ax3 + (b – 2a)x2 + (c – 2b) x – 2c + k
g‘rH$aUmÀ¶m XmoÝhr ~mOybm KZ ~hþnXr AmhoV.
a, b, c.À¶m qH$‘Vr {‘i{dʶmgmR>r x3, x2, x Am{U k À¶m ghJwUH$m§Mr VwbZm Ho$ë¶mg,
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Polynomials 172
1 = a XmoÝhr ~mOybm x3 Mm ghJwUH$
–6 = b – 2a XmoÝhr ~mOybm x2 Mm ghJwUH$
15 = c – 2b XmoÝhr ~mOybm x ghJwUH$
–8 = – 2c + k XmoÝhr ~mOybm pñWa nX
AmVm b, c Am{U k Mr qH$‘V {‘i{dʶmgmR>r Imbrb g‘rH$aUo gmoS>dy.b – 2a = – 6; b = – 6 + 2a = – 6 + 2(1) = – 4c – 2b = 15; c = 15 + 2b = 15 + 2(–4) = 7
–2c + k = –8; k = – 8 + 2c = – 8 + 2(7) = 6
q(x)= ax2 + bx + c = (1)x2 + (–4)x + 7 = x2 – 4x + 7 Am{U r(x) = k = 6
^mJmH$ma = x2 – 4x + 7 Am{U ~mH$s 6.
^mJmH$ma H$m¶m©dbrMo AmUIr H$m§hr Cn¶moJ Imbrb CXmhaUmV ñnï> Ho$bobo AmhoV.
CXmhaU 4 : 6x4+13x3+30x +20. ‘YyZ H$m¶ dOm Ho$ë¶mg ¶oUmè¶m ~hþnXrbm 3x2+2x+5 Zo AMyH$ ^mJOmB©b?
CH$b : p(x)= g(x) × q(x) + r(x) [~hþnXtMr ^mJmH$ma H$m¶m©dbr]
= p(x) – r(x) = g(x) × q(x)
ho ñnï> Amho H$s, darb g‘rH$aUmÀ¶m COì¶m ~mOybm ^mOH$ g(x) Zo ^mJ OmVmo.
S>mì¶m ~mOybm gwÜXm ^mOH$mZo ^mJ OmVmo.
åhUyZ, ^mÁ¶ p(x) ‘YyZ ~mH$s r(x) dOm Ho$br Va ˶mbm ^mOH$ g(x) Zo AMyH$nUo ^mJ OmB©b,
AmVm AmnU 6x4 + 13x3 + 13x2 + 30x + 20 by 3x2 + 2x+5Zo mJ XoD$.
2
2
2 3 13 2 5 6
x xx x x 3 2
4
13 13 30 20
6
x x x
x 3 2
( ) ( ) ( )
3
4 10
9
x x
x 2
33 30
9x x
x 2
( ) ( ) ( )
2
6 15
3
x x
x2
15 203
xx
( ) ( ) ( )2 5
17 25
x
x
^mJmH$ma q(x) = 2x2 + 3x – 1
~mH$s r(x) = 17x + 25
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Polynomials 173
17x + 25 ho 6x4 + 13x3 + 13x2 + 30x + 20, ‘YyZ dOm Ho$ë¶mg ¶oUmè¶m ~hþnXrbm by (3x2 +
2x + 5)Zo ^mJ OmB©b.
[Q>rn : p(x) ‘YyZ 17x + 25 dOm H$éZ Am{U Z§Va ¶oUmè¶m ~hþnXrbm 3x2 + 2x + 5 Zo ^mJ XodyZ Vw‘MoCÎma nS>VmiyZ nmhm ]
CXmhaU 5:
p(x) = x4 + 2x3 – 2x2 + x – 1 ¶m ~hþnXr‘ܶo H$m¶ {‘i{dë¶mg {‘iUmè¶m ~hþnXrbm x2 + 2x – 3 ZonyU© ^mJ OmB©b?
CH$b : p(x) = g(x) × q(x) + r(x) ^mJmH$ma H$m¶m©dbr.
= p(x) – r(x) = g(x) × q(x)= p(x) + {–r(x)} = g(x) × q(x)
ho ñnï> hmoVo H$r COì¶m ~mOybm g(x) Zo ^mJ OmVmo.
S>mì¶m ~mOybm gwÜXm g(x) Zo ^mJ OmVmo.
åhUyZ, Oa p(x) ‘ܶo –r(x) {‘i{dbo Va {‘iUmè¶m ~hþnXrbm g(x) Zo ^mJ OmVmo.
AmVm AmnU ~mH$s r(x) emoYʶmgmR>r p(x) bm g(x) Zo ^mJ XoD$.
2
2
12 3
xx x x 3 2
4
2 2 1x x x
x 3 2
( ) ( ) ( )
2
2 3x x
x2
1xx 2
( ) ( ) ( )2 3
2
x
x
r (x) = -x + 2
- { r(x)} = x - 2
åhUyZ p(x) ‘ܶo (x – 2) {‘i{dë¶mg {‘iUmè¶m ~hþnXrbm g(x) Zo nyU© ^mJ OmB©b.
CXmhaU g§J«h : 8.2
1. Imbrb à˶oH$ àH$mam‘ܶo p(x) bm g(x) Zo ^mJm. Am{U ^mJmH$ma H$m¶m©dbr nS>VmiyZ nmhm.
(i) p(x) = x2 + 4x + 4 g(x) = x + 2
(ii) p(x) = 2x2 – 9x + 9 g(x) = x – 3
(iii) p(x) = x3 + 4x2 – 5x + 6 g(x) = x + 1
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Polynomials 174
(iv) p(x) = x4 – 3x2 – 4 g(x) = x + 2
(v) p(x) = x3 – 1 g(x) = x – 1
(vi) p(x) = x4 – 4x2 + 12x + 9 g(x) = x2 + 2x – 3
2.^mOH$ g(x) emoYm, Ooìhm ~hþnXr p(x) = 4x3 + 2x2 – 10x + 2 bm g(x) Zo ^mJbo Am{U ^mJmH$ma d ~mH$sho AZwH«$‘o (2x2 + 4x + 1) Am{U 5 AmhoV.
3. p(x) = x3 – 3x2 + x + 2 ¶m ~hþnXrbm g(x) Zo ^mJbo AgVm ^mJmH$ma d ~mH$s AZwH«$‘o (x – 2) Am{U
(–2x + 4) ¶oV AgVrb Va g(x) ~hþnXr emoYm.
4. ~hþnXr p(x) bm g(x),Zo ^mJë¶mg {‘iUmam ^mJmH$ma q(x) Am{U ~mH$s r(x) Imbrb H$moï>H$mV {XboboAmho. à˶oH$ àH$mamV p(x) emoYm.
A.Z§ p(x) g(x) q(x) r(x)i ? x – 2 x2 - x + 1 4i i ? x + 3 2x2 + x + 5 3x + 1ii i ? 2x + 1 x3 + 3x2 – x + 1 0iv ? x – 1 x3 – x2 – x – 1 2x – 4v ? x2 + 2x + 1 x4 – 2x2 + 5x – 7 4x + 12
5. à˶j ^mJmH$ma Z H$aVm p(x) bm g(x) Zo ^mJm. Am{U ^mJmH$ma d ~mH$s emoYyZ H$mT>m.
(i) p(x) = x2 + 7x + 10 g(x) = x - 2
(ii) p(x) = x3 + 4x2 - 6x + 2 g(x) = x - 3
6. (x3 + 5x2 + 5x + 8) ‘YyZ H$m¶ dOm H$amdo åhUOo {‘iUmar ~hþnXr (x2 + 3x - 2) Zo nyU© mJ OmUmarAgob?
7. (x4 - 1) ‘ܶo H$m¶ {‘idmdo åhUOo ˶mbm (x2 + 2x + 1) Zo AMyH$nUo ^mJ OmB©b?
eof {gÜXm§V [Remainder Theorem]
[XK© ^mJmH$ma nÜXVrZo VgoM ^mJmH$ma H$m¶m©dbrZo ~hþnXtMm ^mJmH$ma H$aUo Vwåhmbm ‘m{hV Amho.
AmVm AmnU H$m§hr CXmhaUo nmhy OoWo p(x) ¶m ~hþnXrbm (x-a) Z‘wݶmVrb aofr¶ ~hþnXr g(x )Zo ^mJOmVmo.
Imbrb H$moîQ>H$mV {Xboë¶m g{dñVa ‘m{hVrMm Aä¶mg H$am.
CXm. ^mÁ¶ p(x) ^mOH$^ ^mJmH$ma ~mH$sg(x) = x – a q(x) r(x)
1. 4x2 – 7x + 9 x – 2 4x + 1 +11
2 8x3 – 18x2 + 23x + 12 x – 3 8x2 + 6x + 41 +135
3. x5 + a5 x – a x4 + ax3 + a2x2 + a3x + a4 2a5
{ZarjU H$am H$s, ~mH$s pñWa nX Amho.
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Polynomials 175
Á¶m AWu g(x) = x – a hr aofr¶ ~hþnXr Amho, {VMr H$moQ>r ~amo~a 1 Amho.
Amåhr OmUVmo H$s, r(x) Mr H$moQ>r g(x) Mr H$moQ>r.
r(x) Mr H$moQ>r ewݶ Amho.
AmVm AmnU Xþgao CXmhaU Kody.
(x6+4x5-9x2+15) bm x-2 ^mJë¶mg ~mH$s H$m¶ {‘iob?
~mH$s emoYʶmgmR>r Amåhr {XK© ^mJmH$ma nÕV dmnaVmo. hr nÕV ’$maM ‘moR>r Am{U doi bmJUmar Amho.
Xþgè¶m EImÚm bKw Am{U gmo߶m nÜXVrZo ~mH$s emoYZo e³¶ Amho H$m?
AmVm AmnU Vr nÜXV {eHy$.
¶m AJmoXa MMm© Hoo$bobo, OoWo ~mH$s emoYʶmgmR>r XrK© ^mJmH$ma nÜXVrMm Cn¶moJ Ho$bobo CXmhaU Kody.
CXmhaU 1: 4x2 – 7x + 9 bm x – 2 Zo ^mJm. ¶oWo ^mÁ¶ p(x)= 4x2-7x+9
CH$b : ^mOH$ g(x)= x-a= x-2
Oa x – 2=0 Va x= 2
x = 2 KoD$Z p(x) Mr H$s¨‘V H$mT>m.
p(x)= 4(2)2 -7(2)+9 = 4x4-14+9
p(x) = 16-14 + 9
p(x) = 11
bjmV ¿¶m H$s p(2) Mr {‘imbobr qH$‘V {XK© ^mJmH$ma nÕVrZo {‘iUmè¶m ~mH$sBVH$s Amho.
CXmhaU 2: 8x3 – 18x2 + 23x + 12 bm x – 3 Zo ^mJm.
CH$b :
¶oWo p(x)= 8x3 – 18x2 + 23x + 12
g(x) = x – 3
Oa x-3= 0, x=3
x=3 KoD$Z p(x) Mr qH$‘V H$mT>y.
p(3) = 8x(3)3 -18(3)2 + 23(3)+12
=216-162 + 69+12=135
p(3) = 135
{XK© ^mJmH$ma nÕVrZo {‘iUmè¶m ~mH$ser VwbZm H$am.
CXmhaU 3 : x5 + a5 bm x – a Zo ^mJm. ¶oWo p(x)= x5+a5 Am{U g(x)= x--a
Oa x--a=0 Va x-=a
x-=a KoD$Z p(x) Mr qH$‘V H$mT>ë¶mg Amåhmbm {‘iVo.
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Polynomials 176
p(a)= a5+a5=2a5
{XK© ^mJmH$ma nÕVrZo {‘iUmè¶m ~mH$ser p(a) $À¶m qH$‘VrMr VwbZm H$am.
darb à˶oH$ CXmhaUm‘ܶo, Ooìhm mÁ¶ p(x) bm ^mOH$ g(x) = x – a Zo ^mJ {Xbm Voìhm ^mJmH$ma g(x)Am{U ~mH$s r(x) {‘imbr.
darb CXmhaUo g{dñVa Imbrb H$moï>H$mV ‘m§S>m. eodQ>À¶m XmoZ aH$mݶm§Mr VwbZm H$am.
CXm. ^mÁ¶ p(x) ^mOH $ p(a)Mr XrK© ^mJmH$ma nÜXXVrZog(x) = x – a qH$‘V {‘imbobr ~mH$s
1. 4x2 – 7x + 9 x – 2 p(2) = +11 +11
2 8x3 – 18x2 + 23x + 12 x – 3 p(3) = +135 +135
3. x5 + a5 x – a p(a) = +2a5 +2a5
darb H$moï>H$mdéZ ho ñnï> hmoVo H$s, p(a) Mr qH$‘V Am{U ~mH$s gma»¶mM AmhoV.
Amåhr {ZîH$f© H$mTy> eH$Vmo H$s,
Oa ~hþnXr p(x) bm aofr¶ ~hþnXr (x – a) Zo ^mJbo Va ~mH$s p(a) Amho.
¶mbmM eof {gÜXm§V Ago åhUVmV.
AmVm, AmnU (x6 + 4x5 – 9x2 + 15) bm aofr¶ {ÛnXr (x – 2) Zo ^mJë¶mZo {‘iUmar ~mH$s H$mTy>.
p(x) = x6 + 4x5 – 9x2 + 15
g(x) = x – 2 Oa x – 2=0 Va x = 2
p(2) = 26 + 4.25 – 9.22 + 15 = 64 + 128 – 36 + 15 = 207-36=171
p(2) = 171
à˶j ^mJmH$ma Z H$aVm (x6 + 4x5 – 9x2 + 15) bm (x – 2) Zo ^mJë¶mg {‘iUmar ~mH$s Amåhr emoYbr Amho.
[[Q>n : [XK© ^mJmH$ma nÜXVrZo CÎma nS>VmiyZ nmhm]
{ZarjU Ho$ë¶mg ho ñnï> hmoVo H$s, Ooìhm ^mOH$ hm {ÛnXr Am{U (x – a) ¶m aofr¶ Z‘wݶmV AgVmo VoìhmMeof {gÜXm§V Cn¶wº$ Amho.
Amåhr ho gwÜXm Z‘yX H$é H$s,
* Ooìhm ^mOH$ (x – a), Z‘wݶmV AgVmo V|ìhm ~mH$s p(a) AgVo.* Ooìhm ^mOH$ (x + a), Z‘wݶmV AgVmo V|ìhm ~mH$s p(–a). AgVo.
H$maU (x + a) hoM {x – (–a)} Agohr {bhrVm ¶oVo.AmVm AmnU eof {gÜXm§VmMo {dYmZ {gÜX H$é¶m.eof {gÜXm§V : Oa ~hþnXr p(x) bm (x – a)Zo ^mJbo Va ~mH$s p(a) BVH$s AgVo.{gÜXVm : Ooìhm ~hþnXr p(x) bm (x – a) Zo ^mJbo OmVo Voìhm ^mJmH$ma H$m¶m©dbrZwgma {‘iUmam ^mJmH$ma q(x)Am{U pñWa ~mH$s r Aer AgVo H$s,p(x) = (x – a). q(x) + r
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Polynomials 177
p(a) = (a – a). q(a) + r = 0.q(a) + r
p(a) = r åhUyZ ~mH$s p(a) Amho.
Oa p(x) bm (x + a) Zo ^mJbo Va ~mH$s p(–a) AgVo.
Oa p (x) bm (ax + b) Zo ^mJbo Va ~mH$sbp
a AgVo.
gm oS >{dbobr CXmhaUo
CXmhaU 1: p(x) = x3 – 4x2 + 3x + 1 ¶m ~hþnXrbm Ooìhm (x–1) Zo ^mJbo AgVm ~mH$s H$mT>m.
CH$b :eof {gÜXm§VmZo Amdí¶H$ AgUmar ~mH$s p(1) er g‘mZ Amho.
p(x) = x3 – 4x2 + 3x + 1p(1) = 13 – 4(1)2 + 3(1) + 1 = 1 – 4 + 3 + 1 = 1
Amdí¶H$ ~mH$s = p(1) = 1
CXmhaU 2: p(x) = x3 – 6x2 + 2x – 4 ¶m ~hþnXrbm, Ooìhm g(x) = 3x – 1 Zo ^mJbo AgVm ~mH$sH$mT>m.
CH$b :¶oWo, g(x) = 3x – 1. eof {gÜXm§V bmJy H$aʶmgmR>r (dmnaʶmgmR>r) (3x-1) bm (x - a) ¶m ñdénmVénm§VarV Ho$bo nm{hOo.
3x – 113 (3x – 1) x –
13 g(x) = 3
13
x
eof {gÜXm§VmZo, r(x) = p(a) = p13
AmVm, p(x) =x3 – 6x2 + 2x – 4 p13 =
313 – 6
213 + 2
13 – 4 =
127
–69
+23
– 4
=1 18 18 108
27 =
10727
~mH$s p 13
=10727
CXmhaU 3: (ax3 + 3x2 – 13) Am{U (2x3 – 4x + a) ¶m ~hþnXtZm (x–3)Zo ^mJbo. Oa XmoÝhràH$mam‘ܶo ~mH$s g‘mZ Agob Va a Mr qH$‘V emoYm.
CH$b :p(x) = ax3 + 3x2 – 13g(x) = 2x3 – 4x + a
eof {gÜXm§VmZwgma, p(3) Am{U g(3) ¶m XmoZ ~mH$s hmo¶.
{Xboë¶m AQ>rZwgma, p(3) = g(3)
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Polynomials 178
p(3) = a. 33 + 3.32 – 13 = 27a + 27 – 13 = 27a + 14
g(3) = 2.33 – 4.3 + a= 54 – 12 + a = 42 + a
na§Vw p(3) = g(3), åhUyZ
27a + 14 = 42 + a
26a = 28
a =2826
=1413
CXmhaU 4: XmoZ ~hþnXr (2x3 + x2 – 6ax + 7) Am{U (x3 + 2ax2 – 12x + 4) ¶m§Zm AZwH«$‘o (x+1)
Am{U (x–1) Zo ^mJbo. Oa R1 Am{U R2 ¶m ~mH$s AgyZ 2R1 + 3R2 = 27, Agob
Va a Mr qH$‘V emoYm.
CH$b : p(x) = 2x3 + x2 – 6ax + 7
f(x) =x3 + 2ax2 – 12x + 4
Oa, p(x) bm (x + 1) Zo ^mJbo Va ~mH$s R1 Amho.
R1 = p(–1)
R1 = 2(–1)3 + (–1)2 – 6a(–1) + 7 = –2 + 1 + 6a + 7
R1 = 6a + 6
Am{U,
Oa f(x) bm (x-1) Zo ^mJbo Va ~mH$s R2 Amho.
R2 = p(1)
R2 = 13 + 2a(1)2 – 12(1) + 4 = 1 + 2a – 12 + 4
R2 = 2a – 7
R1 Am{U R2 À¶m qH$‘Vr 2R1 + 3R2 = 27, ‘ܶo dmnê$
2 (6a + 6) + 3(2a – 7) = 27
12a + 12 + 6a – 21 = 27
18a – 9 = 27 18a = 27 + 9 = 36 a =3618
a = 2
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Polynomials 179
ñdmܶm¶ 8.3
1. Imbrb à˶oH$ CXmhaUmbm eof {gÜXm§VmMm dmna H$am Am{U Ooìhm p(x) bm g(x). Zo ^mJbo AgVm ~mH$sH$mT>m.
à˶j ^mJmH$mamZo CÎma nS>Vmim.
(i) p(x) = x3 + 3x2 – 5x + 8 g(x) = x – 3
(ii) p(x) = 4x3 – 10x2 + 12x – 3 g(x) = x + 1
(iii) p(x) = 2x4 – 5x2 + 15x – 6 g(x) = x – 2
(iv) p(x) = 4x3 – 12x2 + 14x – 3 g(x) = 2x – 1
(v) p(x) = 7x3 – x2 + 2x – 1 g(x) = 1 – 2x
2. Oa (2x3 + ax2 + 3x – 5) Am{U (x3 + x2 – 4x – a) ¶m ~hþnXrZm Ooìhm (x-1) Zo mJbo AgVm gmaIrM(g‘mZ) ~mH$s amhVo Va a.Mr qH$‘V H$mT>m.
3. (2x3 – 5x2 + x + a) Am{U (ax 3+ 2x2 -3) ¶m ~hþnXrZm Ooìhm (x -2) ^mJbo AgVm AZwH«$‘o R1 Am{UR2 ~mH$s amhVo. Va à˶oH$ CXmhaUmVrb a Mr qH$‘V H$mT>m.
Oa
(i) R1=R2 (ii) 2R1+ R2=0 (iii) R1+R2 =0 (iv) R1- 2R2=0
Ad¶d à‘o¶ (Factor Theorem)
Amåhr ho Aä¶mgbo Amho H$s, Oa ~hþnXr p(x) bm (x–a) ¶m ñdê$nmVrb {ÛnXrZo ^mJbo AgVm ~mH$s p(a){‘iVo. Amåhr ho gwÕm nm{hbo Amho H$s p(a) À¶m qH$‘VrÀ¶m XmoZ e³¶Vm AmhoV. ˶m åhUOo p(a)=0 qH$dmp(a)=0
^mÁ¶ Am{U ^mOH$mer g§~§YrV Agbobm H$moU˶mhr àH$maMm JwUY‘© p(a) Mr qH$‘V {ZYm©arV H$aVmo H$m?Oa p(a)=0 Mr H$moUVrhr {deofVm: Amho H$m?
eof {gÕm§VmMm {dñVma hm AmUIr EH$m ~hþnXrMm Hw$VwhbmË‘H$ JwUY‘© XoVmo. ˶m JwUY‘m©Mm Aä¶mg H$ê$.
A§H$J{UVm‘Yrb CXmhaUo KodyZ àW‘V: JwUY‘©m§À¶m ñnï>rH$aUmMm Aä¶mg H$ê$.
CXmhaU 1:
¶oWo 6 bm 2 Zo nyU© nUo ^mJ OmVmo Am{U ~mH$s eyݶ amhVo.
2x3=6
^mOH$ 2 Am{U ^mJmH$ma 3 ho 6 Mo Ad¶d AmhoV.
32 6
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Polynomials 180
CXmhaU 2 :
¶oWo, 6 Zo 14 bm nyU©nUo ^mJ OmV Zmhr Am{U ~mH$s hr eyݶmBVH$s Zmhr
(eyݶmBVH$s Zmhr. (ewݶmer g‘mZ).
^mOH$ 6 hm 14 Ad¶d Zmhr.
2x3=6
^mOH$ 2 Am{U ^mJmH$ma 3 ho 6 Mo Ad¶d AmhoV.
darb XmoZ CXmhaUmdéZ Amåhr Agm {ZîH$f© H$mT>Vmo H$s
* Oa ~mH$s hr eyݶmBVH$s (g‘mZ) Agob Va ^mOH$ hm ^mÁ¶mMm Ad¶d AgVmo.
* Oa ~mH$s hr eyݶmBVH$s (g‘mZ) Zgob Va ^mOH$ hm ^mÁ¶mMm Ad¶d ZgVmo.
* Oa ^mOH$ hm ^mÁ¶mMm Ad¶d Agob Va ^mJmH$ma gwÜXm ^mÁ¶mMm Ad¶d AgVmo.
åhUyZ,
Oa ~mH$s hr eyݶmBVH$s (eyݶm g‘mZ) Agob Va ^mOH$ Am{U ^mJmH$ma ho XmoÝhr ^mÁ¶mMo Ad¶dAgVmV.
Oa ~mH$s hr eyݶmBVH$s (eyݶmg‘mZ) Zgob Va ^mOH$ hm ^mÁ¶mMm Ad¶d ZgVmo Am{U ^mJmH$ma hm^mÁ¶mMm Ad¶d Agy eHo$b qH$dm AgUma gwÜXm Zmhr.
hm JwUY‘© ~hþnXrZmgwÜXm bmJw nS>Vmo. Oa EH$m ~hþnXr p(x) bm Xþgè¶m ~hþnXr g(x) Zo ^mJbo AgVm ~mH$seyݶ Agob Va ^mOH$ g(x) hm p(x) Mm Ad¶d AgVmo
AmVm hm JwUY‘© ñnîQ> H$aʶmgmR>r eof {gÜXm§VmMm dmna H$é.
Oa p(a) ho eyݶ Amho ¶mMm AW© Agm H$s ~mH$s eyݶ Amho. Am{U (x – a) hm ~hþnXr p(x) MmAd¶d AgVmo.
{dYmZmMm ì¶Ë¶mg (CbQ> AW©) XoIrb g˶ Amho.
Oa (x – a) hm ~hþnXr p(x) Mm Ad¶d Amho. ¶mMm AW© Agm H$s ~mH$s eyݶ Amho Am{U p(a) hoe yݶmBVHo$ Amho.
Amåhr Ago {gÕ H$ê$ H$s
* Oa p(a) = 0, Va (x – a) hm p(x) Mm Ad¶d Amho.
* Ooìhm (x – a) hm p(x), Mm Ad¶d AgVmo Voìhm p(a) = 0
¶bm ~hþnXrMm Ad¶d à‘o¶ åhUVmV.
Ad¶d à‘o¶ hm eof à‘o¶mMm AmUIr EH$ Cn‘o¶ Amho.
Ooìhm ~hþnXr p(x) bm (x – a) ¶m ñdénmVrb aofr¶ ~hþnXrZo ^mJ OmVmo ’$º$ VoìhmM Ad¶d {gÜXm§V dmnabm OmVmo. (bmJy Ho$bm OmVmo) ho EH$ A˶§V ‘hËdmMo Zm|X H$aʶmgmaIo Amho.
26 14
122
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Polynomials 181
Oa aofr¶ ~hþnXr hr (x – a) ¶m ñdénmV Zgob Va Vr nwÝhm à‘m{UV Z‘wݶmV {bhm Am{U Z§Va Ad¶d à‘o¶ bmJy H$am (dmnam.)
ho Aä¶mgʶmgmR>r Imbrb {dYmZm§Mo {ZarjU H$am.
* Oa p(a) = 0 Va (x – a) hm p(x) ~hþnXrMm Ad¶d Amho.
* Oa p(–a) = 0 Va x + a hm p(x) ~hþnXrMm Ad¶d Amho.
* Oa pba = 0 Va (ax – b) hm ~hþnXr p(x) Mm Ad¶d Amho.
* Oa pb
a = 0 Va (ax + b) hm ~hþnXr p(x) Mm Ad¶d Amho.
* Oa p(a) = 0 Am{U p(b) = 0 Va (x – a) (x – b) ho ~hþnXr p(x) Mo Ad¶d AmhoV.AmVm Ad¶d à‘o¶mMm Cn¶moJ H$éZ H$m§hr CXmhaUo gmoS>dy.
gmoS>{dbobr CXmhaUo
CXmhaU 1: (x + 2) hm (x3 – 4x2 + 2x + 20)¶m ~hþnXrMm Ad¶d Amho Ago XmIdm.
CH$b : p(x) = x3 – 4x2 – 2x + 20 ‘mZy
Ad¶d à‘o¶mZo (x + 2) hm p(x) Mm Ad¶d Amho Oa p(–2) = 0.
(x + 2) hm p(x) Mm Ad¶d Amho ho Xe©{dUo nwaogo Amho.
AmVm, p(x) = x3 – 4x2 – 2x + 20
p(–2) = (–2)3 – 4(–2)2 – 2(–2) + 20
= –8 –16 + 4 + 20 = 0
(x + 2 hm p(x) = x3 – 4x2 – 2x + 20 Mm Ad¶d Amho.
CXmhaU 2: (x – 1) hm (xn – 1). Mm Ad¶d Amho ho XmIdm.
CH$b: p(x) = xn – 1 ‘mZy.
(x – 1) hm (xn – 1), Mm Ad¶d Amho ho Xe©{dʶmgmR>r p(1) = 0.ho XmI{dUo nwaogo Amho.
AmVm, p(x) = xn – 1
p(1) = 1n – 1 = 1 – 1 = 0
(x + 1) hm (xn-1) Mm Ad¶d Amho.
CXmhaU 3: Oa (x - a) hm (x3 – a2x + x + 2).Mm Ad¶d Agob. Va a Mr qH$‘V H$mT>m.
CH$b : Oa p(a) = 0 Va Ad¶d à‘o¶mZo (x – a) hm p(x) Mm Ad¶d Amho.
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Polynomials 182
p(a) = a3 - a2 x a + a + 2 = 0
a3 - a3 + a + 2 = 0 a + 2 = 0 a = -2
CXmhaU 4: à˶j ^mJmH$ma Z H$aVm (x4 - 4x2 + 12x - 9) bm (x2 + 2x - 3) Zo nyU©nUo ^mJ OmVmo ho {gÜXH$am.
CH$b : p(x) = x4 – 4x2 + 12x – 9 g(x) =x2 + 2x – 3
g(x) = (x + 3) (x – 1)
åhUyZ, (x + 3) Am{U (x – 1) ho g(x) Mo Ad¶d AmhoV.
p(x) bm g(x) Zo nyU©nUo mJ OmVmo ho {gÜX H$aʶmgmR>r p(x) bm (x + 3) Am{U (x – 1) Zo mJ OmVmoho Xe©{dUo nwaogo Amho.
(x + 3) Am{U (x – 1) ho p(x) Mo Ad¶d AmhoV ho XmIdy.
AmVm, p(x) = x4 – 4x2 + 12x – 9
p(-3) = (-3)4 – 4(-3)2 + 12(–3)–9
= 81 – 36 – 36 – 9 = 81 – 81 = 0
p(-3) = 0
p(1) = (1)4 – 4(1)2 + 12(1) – 9
= 1 – 4 + 12 – 9 = 13 – 13 = 0
p(1) = 0
(x + 3) Am{U (x – 1) ho p(x) Mo Ad¶d AmhoV.
g(x) = (x + 3) (x – 1) ho gwÜXm p(x) Mo Ad¶d AmhoV.
åhUyZ, p(x) bm g(x) Zo nyU©nUo ^mJ OmVmo.
(x4 – 4x2 + 12x – 9) bm (x2 + 2x – 3) Zo nyU©nUo ^mJ OmVmo
ñdmܶm¶ 8.4
1. Imbrb à˶oH$ CXmhaUm‘ܶo Ad¶d à‘o¶mZo g(x) hm ~hþnXr p(x) Mm Ad¶d Amho qH$dm Zmhr Vo emoYm
(i) p(x) = x3 – 3x2 + 6x – 20 g(x) = x – 2
(ii) p(x) = 2x4 + x3 + 4x2 – x – 7 g(x) = x + 2
(iii) p(x) = 3x4 + 3x2 - 4x – 11 g(x) = x –12
(iv) p(x) = 3x3 + x2 – 20x + 12 g(x) = 3x – 2
(v) p(x) = 2x4 + 3x3 – 2x2 – 9x – 12 g(x) = x2 – 3
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Polynomials 183
2.Oa (x - 5) hm (x3 – 3x2 + ax – 10) Mm Ad¶d Agob Va a Mr qH$‘V H$mT>m.3. Oa (x3 + ax2 -bx +10) bm (x2 - 3x +2) Zo ^mJ OmV Agob Va a Am{U b Mr qH$‘V H$mT>m.
4.Oa (x –2) Am{U12
x ho XmoÝhr (ax2 + 5x + b), Mo Ad¶d AmhoV Va a = b Ago XmIdm.
g§íbofH$ ^mJmH$ma : [Synthetic Division]‘mJrb {d^mJmV Amåhr eof {gÜXm§VmÀ¶m Cn¶moJm§Mm Aä¶mg Ho$bobm Amho AmVm AmnU ^mJmH$ma Am{U ~mH$sA{YH$ gmo߶m [aVrZo H$mT>ʶmÀ¶m eof {gÜXm§VmÀ¶m Xþgè¶m Cn¶moJmMm Aä¶mg H$é.^mJmH$ma Am{U ~mH$s hr {XK© ^mJmH$ma nÜXVrZo H$mT>Uo ho Amåhmbm ‘m{hV Amho. hr {XK© nÜXV Amho ho AmåhrAmoiIbo Amho.
˶mZ§Va à˶j ^mJmH$ma Z H$aVm eof {gÜXm§VmMm Cn¶moJ H$éZ ~mH$s H$mT>Uo ho Amåhr Aä¶mgbo Amho.eof {gÜXm§VmZo ~mH$s gmo߶m Am{U ObX[a˶m H$mT>Vm ¶oVo ¶mV e§H$m Zmhr.~mH$s Zìho Va ^mJmH$ma gwÜXm H$mT>ʶmMr X þgar ’$ma gmonr Am{U ObX nÜXV Amho.¶m eof {gÜXm§VmMm dmna Ho$boë¶m A˶§V gmo߶m nÜXVrbm g§íbofH$ ^mJmH$ma Ago åhUVmV.
AmVm ^mJmH$ma Am{U ~mH$s H$mT>ʶmÀ¶m g§íbofH$ ^mJmH$ma nÜXVrMo Aܶ¶Z H$é. Ooìhm ~hþnXrbm(x – a) ¶m {ÛnXrZo ^mJ OmVmo. OoWo a hm pñWam§H$ Amho.
Imbrb CXmhaUo Aä¶mgm.
CXmhaU 1 : p(x) = x4 – 3x + 5 ¶m ~hþnXrMm {dMma H$am.
p(x) bm (x – 4) ¶m ñdénmVrb aofr¶ ~hþnXrZo ({ÛnXr) ^mJ OmVmo Ago g‘Om.
x4 – 3x + 5 bm 4 Zo ^mJm.
x4 – 3x + 5 bm 4 Zo ^mJʶmgmR>r dmnaboë¶m g§íbofH$ ^mJmH$mamÀ¶m nm¶è¶m§Mo {ZarjU H$am.
nm¶ar 1 : g§íbofH$ ^mJmH$mamMr ‘m§S>Ur H$am.
ho H$aʶmMm gmonm ‘mJ© åhUOo àW‘ Vwåhr {XK© ^mJmH$mamMr Am{U Z§Va g§íbofH$ ^mJmH$mamgmR>r ‘m§S>Ur H$am.
{XK© ^mJmH$ma nÜXVr‘ܶo ^mÁ¶ ho Mm¡H$Q>rÀ¶m AmV Am{U ^mOH$ ho Mm¡H$Q>rÀ¶m ~mhoa AgVo.
^mÁ¶ {bhrVmZm ˶mMr nXo KmVm§H$mÀ¶m CVa˶m H«$‘mV {bhrë¶mMr ImÌr H$éZ ¿¶mdr. Oa EImXo nXJmibobo Agë¶mg Vo eyݶ ghJwUH$mZo {bhmdo.
{Xbobm ^mÁ¶ x4 – 3x + 5 Amho.
ho nwÝhm x4 + 0.x3 + 0.x2 – 3x + 5 Ago {bhrVmV.
XrK© ^mJmH$ma ¶mgmaIr {XgVo.
4 3 24 0. 0. 3 5x x x x x
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Polynomials 184
^mÁ¶mVrb à˶oH$ nXm§À¶m ghJwUH$m§Mo {ZarjU H$am.
Vo 1, 0, 0, –3, 5 AmhoV.
^mOH$ x – 4. ‘Yrb a À¶m qH$‘VrMo [ZarjU H$am a Mr qH$‘V 4 Amho
a À¶m ˶m qH$‘Vrbm JwUH$ qH$dm {H«$¶mË‘H$ Ad¶d Ago åhUmV.
AmVm g§íbofH$ ^mJmH$mamMr ‘m§S>Ur H$é. ho Imbrb à‘mUo {XgVo.
^mJmH$mamMo ghJwUH$
‘a’ hm (x - 4) Mm ^mOH$ 1 0 0 3 54
Vwåhr nwÝhm EH$Xm {XK© ^mJmH$ma Am{U g§íbofH$ ^mJmH$mamÀ¶m ‘m§S>UrMr VwbZm H$am.
{XK© ^mJmH$ma g§íbofH$ ^mJmH$ma
4 3 24 0. 0. 3 5x x x x x 1 0 0 3 54
^mÁ¶mVrb nXm§À¶m CVa˶m H«$‘mVrb KmVm§H$mMo ghJwUH$ ho g§íbofH$
^mJmH$mamÀ¶m n{hë¶m n§º$sV {bhrbobo AmhoV ¶mMo {Z[ajU
H$am.
x – 4 ¶m ^mOH$mVrb a Mr qH$‘V 4 hr Mm¡H$Q>rÀ¶m ~mhoa
{bhrbobr Amho.
nwÝhm g§íbofH$ ^mJmH$mamMr ‘m§S>Ur H$éZ Amåhr nÜXV Mmby R>ody.
nm¶ar 2 : n{hbm ghJwUH$ Imbr AmUm.* g§íbofH$ ^mJmH$mamMr ‘m§S>Ur H$aʶmgmR>r AmUIr XmoZ n§º$s {Z‘m©U H$am.
* n{hë¶m n§º$sVrb n{hbo nX ho {Vgè¶m n§º$sVrb n{hbo nX g§~moYyZ Imbr AmUm.nm¶ar 3 : {Vgè¶m n§º$sVrb qH$‘VrMo JwUH$mer JwUmH$ma H$am.
* {Vgè¶m n§º$sV {bhrboë¶m qH$‘VrÀ¶m n{hë¶m nXmbm 4 ZoJwUm (JwUH$mZo)
* ^mÁ¶mVrb Xþgè¶m ghJwUH$mÀ¶m Imbr JwUmH$ma {bhm.ho Xþgè¶m n§º$rVrb n{hbo nX {bhm.nm¶ar 4 : Xþgam ghJwUH$ Am{U JwUmH$ma {‘idm.
* n{hë¶m n§º$sVrb Xwgao nX Am{U Xþgè¶m n§º$sVrb n{hbo nX {‘idm.åhUOo., 0 + 4 = 4
4 hr ~oarO {Vgè¶m n§º$sV {bhm.
4 1 0 0 3 5
14
n{hbr n§º$sXþgar n§º$s{Vgar n§º$s
1 row 4 1 0 0 3 52 row3 row 1
n{hbr n§º$sXþgar n§º$s{Vgar n§º$s
1 row 4 1 0 0 3 52 row3 row
n{hbr n§º$sXþgar n§º$s{Vgar n§º$s
st
nd
rd
1 row 4 1 0 0 3 52 row 4 16
1 43 row
n{hbr n§º$sXþgar n§º$s{Vgar n§º$s
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Polynomials 185
nm¶ar 5: ZdrZ ~oaOoMm JwUH$mer JwUmH$ma H$am.* {Vgè¶m n§º$sVrb Xþgè¶m nXmMm JwUH$mer JwUmH$ma H$am.
åhUOo, 4 × 4 = 16
* n{hë¶m n§º$sÀ¶m {Vgè¶m nXmImbr JwUmH$ma {bhm.nm¶ar 6 : ZdrZ JwUmH$ma Am{U {Vgè¶m ghJwUH$ {‘idm.
* n{hë¶m n§º$sMo {Vgao nX Am{U Xþgè¶m n§º$sMo Xþgao nX {‘idm.* hr ~oarO {Vgè¶m n§º$sMo {Vgao nX åhUyZ {bhm.
nm¶ar 7:* nm¶ar 3 Am{U 4 à‘mUoM nyU© ^mJmH$ma hmoB©n¶ªV nÜXV nwÝhm H$am.
nm¶ar 8: CÎma {bhm.eodQ>À¶m n§º$sVrb g§»¶m ({Vgar n§º$s) hr ^mJmH$ma VgoM ~mH$sMo ghJwUH$ ~ZVo.~hþnXr p(x) Mm KmVm§H$ 4 Am{U ^mOH$mMm KmVm§H$ EH$ AgyZ Vr aofr¶ ~hþnXr Amho. 1.
^mJmH$mamMm KmVm§H$ hm ^mÁ¶mÀ¶m KmVm§H$mnojm EH$ (1) Zo H$‘r AgVmo. ¶oWo ^mJmH$ma hr 3 KmVm§H$ AgUmar~hþnXr KoVbr Va.n{hbr g§»¶m (1) hr x3 Mm ghJwUH$ Amho.Xþgar g§»¶m (4) hr x2 Mm ghJwUH$ Amho.{Vgar g§»¶m (16) hr x Mm ghJwUH$ Amho.Mm¡Wr g§»¶m (61) hr pñWa Amho.nmMdr g§»¶m qH$dm eodQ>Mr g§»¶m (249) hr ~mH$s Amho.^mJmH$ma x3+4x2+16x +61 Am{U ~mH$s 249 Amho.AmVm AmnU {XK© ^mJmH$ma nÜXV Am{U g§íbofH$ ^mJmH$ma nÜXVrMr VwbZm H$ê$. XmoÝhr nÜXVrVrb g‘mZVH$S>o
1 0 0 3 544 16 64 244
1 4 16 61 249
––
3
3
3
3
4 3
2
2
2
2
2
2
4
4
4
44
5
5
3x
3x64x
4 16 61x xx x x x
xx
xx
xx
x
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xx
x
. .
.-
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st
nd
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1 row 4 1 0 0 3 52 row 4 16
1 4 163 row
n{hbr n§º$sXþgar n§º$s{Vgar n§º$s
nmhm.
st
nd
rd
1 row 4 1 0 0 3 52 row 4 16 64 244
1 4 16 61 2493 row
n{hbr n§º$sXþgar n§º$s{Vgar n§º$s
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Polynomials 186
nmhm H$s1.g§íbofH$ ^mJmH$mamVrb n{hë¶m AmoirVrb A§H$ ho ^mÁ¶mMo ghJwUH$ AmhoV.2.{XK© ^mJmH$mamVrb Mm¡H$Q>r‘Yrb ghJwUH$ ho g§ûbofU ^mJmH$mamMr Xþgar Amoi Amho.3.{XK© ^mJmH$mamVrb dVw©i Ho$bobo A§H$ ho g§ûbofU ^mJmH$mamMr {Vgar Amoi Amho.4.^mOH$mMr {H$§‘V ‹(4) hr JwUmH$ma H$ê$Z g§ûbofU ^mJmH$mamÀ¶m Mm¡H$Q>r ~mhoa {b{hbobr Amho.5.^mJmH$mamMo ghJwUH$ ho {Vgè¶m AmoirVrb eodQ>Mr g§»¶m gmoSy>Z ¶oVmV.6.S>mdr H$Sy>Z {Vgè¶m AmoirVrb eodQ>Mr g§»¶m hr ~mH$s Amho.g§íbofH$ ^mJmH$mamdarb AmUIr H$m§hr CXmhaUo Kody.
gmoS>{dbobr CXmhaUo
CXmhaU 1: 3x3 + 11x2 + 34x + 106 bm x – 3 Zo ^mJm.
CH$b : g§íbofH$ ^mJmH$mamMr ‘m§S>Ur H$am Am{U nÕV dmnam.
3 3 11 34 1069 60 282
3 20 94 388^mJmH$mamMoghJwUH$ ~mH$s$
^mJmH$ma 3x2 + 20x + 94 Am{U ~mH$s 388 Amho.
({Q>n : ^mJmH$ma Am{U ~mH$s {bhrVmZm COì¶m ~mOyH$Sy>Z {Vgè¶m n§º$sVrb g§»¶mMm gwÕm Amåhr {dMma H$aVmo.)
n{hbr g§»¶m (388) hr ~mH$s Amho.
Xþgar g§»¶m (94) hr ^mJmH$mamMr pñWa g§»¶m Amho.
x Mm ghJwUH$ (20) hr {Vgar g§»¶m Amho.
Mm¡Wr g§»¶m (3) hr x2 Mm ghJwUH$ Amho.
^mJmH$ma 3x2 + 20x + 94 Am{U ~mH$s 388 Amho.
CXmhaU 2: x6 – 2x5 – x + 2 bm x – 2 Zo ^mJm.
CH$b : ^mÁ¶ ho nwÝhm Ago {bhrVmV.
x6 – 2x5 + 0 . x4 + 0.x3 + 0.x2 – x + 2
AmVm g§íbofH$ ^mJmH$mamZo1 2 0 0 0 1 2 2 0 0 0 0 2
1 0 0 0 0 1 0
– –
––
2
^mJmH$ma x5 – 1 Am{U ~mH$s 0 Amho.
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Polynomials 187
ñdmܶm¶ 8.5
1. g§íbofH$ ^mJmH$mamMm Cn¶moJ H$ê$Z ^mJmH$ma Am{U ~mH$s H$mT>m.
(i) (x3 + x2 – 3x + 5) (x – 1)
(ii) (3x3 – 2x2 + 7x – 5) (x + 3)
(iii) (4x3 – 16x2 – 9x – 36) (x + 2)
(iv) (6x4 – 29x3 + 40x2 – 12) (x – 3)
(v) (8x4 – 27x2 + 6x + 9) (x + 1)
(vi) (3x3 – 4x2 – 10x + 6) (3x – 2)
(vii) (8x4 – 2x2 + 6x – 5) (4x + 1)
(viii) (2x4 – 7x3 – 13x2 + 63x – 48) (2x – 1)
2. (x4 + 10x3 + 35x2 + 50x + 29) bm (x + 4) Zo mJbo AgVm (x3 - ax2 + bx + 6), ^mJmH$ma {‘iVmo Vaa,b Am{U ~mH$s gwÕm H$mT>m.
3. (8x4 - 2x2 + 6x - 7) bm (2x + 1) Z o ^mJbo AgVm(4x3 + px2 - qx + 3) ^mJmH$ma {‘iVmo Va p, q Am{U ~mH$s gwÕm H$mT>m.
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Polynomials 188
{XK©
^mJ
mH$ma
nÕ
Ve
of {g
Õm§V
g§íb
ofH$ ^
mJmH
$ma
g(x)
=x-
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x)=
(2x-
1)
=
x-
= 0
x = p
(x) =
2x5 -
3x4 +
8x3 -
2x2 +
x+2
p=
2-3
+8-2
+2
=2
+8-2
-+2
=-
-1-
-+2
= = ==
~mH$
s~m
H$s
~hþnX
tMm ^m
JmH$ma
VrZ
doJdoJ
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$mT>ʶ
mMr nÕ
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måhr
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mho.
Imb
r {Xboë¶
m gm
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oM C
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mho.
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r Vwb
Zm H
$am.
~mH$
s
19
24
107
22
7 29
12
54
[[
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Polynomials 189
~hþnXr
~hþnXrMrH$moQ>r
~hþnXrMrqH$‘V
~hþnXrMoeyݶ
~hþnXrÀ¶m ^mJmH$mamMrH$m¶m©dbrp(x) = q(x) x g(x )+r(x)
OoWo r(x)=0 qH$dmr(x) Mr H$moQ>r g(x) Mr H$moQ>r
eof{gÕm§Vp(x)(x-a)
Va r(x)=p(a)
^mÁ¶ Am{U ^mOH$ H$mT>Uo
à˶j ^mJmH$ma Z H$aVm^mJmH$ma Am{U ~mH$sH$mT>Uo.
g§íbofH$^mJmH$ma
Oa p(a)=0Va (x-a) hmp(x) MmAd¶d Amhoo.
Oa (x-a) hmp(x) Mm Ad¶dAmho Va p(a)=0
Ad¶d à‘o¶
CÎma o
ñdmܶm¶ : 8.1
1) (i) 2 (ii) 2 (iii) 3 (iv) 3 (v) 3 2) (i) 6 (ii) 0 (iii)18 (iv)12 (v)12
3) 23 (ii)-11 (iii) 594 (iv) 30 4) (i) 1 0
3=f (- ) hmo¶ (ii)p 2 =0- ,hmo¶
(iii) g -4 45 = , Zm§hr (iv) p (3)=0, hmo¶ ; p (-1)=0, hmo¶; 1 0
3=-p , hmo¶
5) (i) x=-2 (ii) x=-2 qH$dm x=5 (iii) -72=a qH$dm 7
2=a (iv) 21a =
6) k = -3 7) k = 9
ñdmܶm¶ : 8.2
1) (i) q (x) = x + 2, r (x) = 0 (ii) q (x) = x + 3, r (x) = 0
(iii) q (x) = x2 + 3 x -8, r (x) = 14 (iv) q (x) = x3+ 3 x2 + x-2, r (x) = 0
(v) q (x) = x2 + x + 1, r (x) = 0
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Polynomials 190
2) g (x) 2 x - 3 3) g (x) = x2 - x + 1 4) (i) p(x) = x3- 3x2 + 3x +2
(ii) p(x) = x3+ 7x2 + 11x +16 (iii) p(x) = x4+ 7x3 + x2 + x +1
(iv) p(x) = x4+ 2x3 + 2x -3 (v) p(x) = x6+ 2x5 - x4 + x3 + x2 -5x+5
5) (i) q (x) = x + 9, r (x) = 28 (ii) q (x) = x2 + 7x + 15, r (x) = 47
6) (x + 12 ) 7.) 4 x + 4
ñdmܶm¶ : 8.3
1) (i) r(x ) =47 (ii) r(x ) = - 29 (iii) r(x ) =36 (iv) 32r (x)= (v) 5
8r (x)=
2) (i) a=-1 3)(i) a=-1 (ii) -1 10a= (iii) -4
5a=
ñdmܶm¶ : 8.4
2) a = -8 3) a=2, b = 13
ñdmܶm¶ : 8.5
1) (i) q (x) = x2 + 2 x -1, r (x) = 4 (ii) q (x) = 3 x2 -11x + 40, r (x) = -125
(iii) q (x) = 4x2 -24x + 39, r (x) = -114 (iv) q (x) = 6x3 -11x2 + 7x +21, r (x) = 51
(v) q (x) = 8x3 -8x2 -19x +25, r (x) = -16 (vi) 34 149 9
23
2q (x) =x - x - , r (x)= -
(vii) r (x)x + 3 51 -2118 32 32
12
3 2q (x) = x -2 x - , =
(viii) 3 r(x)x + 55 -418 2 23 2q (x) = x - x - , =
2) a=- 6, b=11, r(x) = 5 3) p==2, q=0, r (x) = -10
*********
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¶m KQ>H$m‘wio Vwåhmbm ¶mMo gwb^rH$aU hmoVo.
* dJ© g‘rH$aU, dJ© Ed dJ© Am{U AdJ© Ed dJ©
g‘rH$aUm§Mr ì¶m»¶m H$aUo.
* dJ© Ed dJ© g‘rH$aUo gmoS>{dUo.
AdJ© Ed dJ© g‘rH$aUo Ad¶dr H$aUmZo gmoS>{dU.
* nyU© dJ© nÕVrZo dJ© g‘rH$aUo gmoS>{dU.
* dJ© g‘rH$aUm§Mr ~rOo H$mT>ʶmMo gyÌ aMUo.
* gyÌmMm Cn¶moJ H$ê$Z dJ© g‘rH$aUo gmoS>{dUo.
* dJ© g‘rH$aUm§Mo AmboI H$mT>mUo.
* AmboImZo dJ© g‘rH$aUo gmoS>{dUo.
* dJ© g‘rH$aUm§Mr ~rOo Am{U ghJwUH$ ¶m‘Yrb
g§~§Y àñWm{nV H$aUo.
* dJ© g‘rH$aUo aMUo.
* dJ© g‘rH$aUmMo {ddoMH$ H$mT>mUo Am{U ~rOm§Mo
ñdê$n ñnï> H$aUo.
dJ© g‘rH$aUo
* dJ© amer Am{U dJ© g‘rH$aU* dJ© Ed dJ© Am{U AdJ© Ed dJ©
g‘rH$aUo* dJ© g‘rH$aUmMr CH$b
(dJ© g‘rH$aUo gmoS>{dUo)* Ad¶drH$aU nÕV* nyU© dJ© nÕV* gyÌ nÕV* AmboI nÕV* ~rOo Am{U ghJwUH$ ¶m‘Yrb g§~§Y* dJ© g‘rH$aUo aMUo (V¶ma H$aUo)
9
Brahmagupta(A.D 598-665, India)
Solving of quadratic equationsin general form is often creditedto ancient Indianmathematicians. Brahmaguptagave an explicit formula tosolve a quadratic equationof the form ax2 + bx = c. LaterSridharacharya (A.D. 1025)derived a formula, now knownas the quadratic formula, forsolving a quadratic equation bythe method of completing thesquare.
An equation means nothing tome, unless it expresses a
thought of God.- Srinivas Ramanujan
(Quadratic Equations)
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192 UNIT-9
g§»¶mÀ¶m Ioim~Ôb Amåhr n[a{MV AmhmoV. AmVm AmnU Aer XmoZ CXmhaUo {dMmamV KoD$.
CXmhaU 1 CXmhaU 2
* eyݶ ahrV nyU© g§»¶m ¿¶m. * eyݶ ahrV nyU© g§»¶m ¿¶m.* ¶m‘ܶo 7 {‘idm. * ˶m‘ܶo 7 {‘idm.* ho 12 er g‘mZ {bhm. * ~oaOobm ˶mM nyU© g§»¶oZo JwUm.* Vr g§»¶m H$moUVr Amho? * ho 12 er g‘mZ {bhm.
* Vr g§»¶m H$moUVr Amho?
g§»¶m H$em H$mT>mb? Vr eyݶ ahrV nyU© g§»¶m 'x' ‘mZy.Oa Amåhr nm¶è¶m§Mo AZwH$aU Ho$ë¶mg Amåhmbm {‘iVo.CXmhaU 1 ‘ܶo, x, x + 7 Am{U x + 7 = 12........(i)
CXmhaU 2 ‘ܶo, x x + 7 Am{U x(x + 7) = 12........(ii)
g‘rH$aU (i), x + 7 = 12 ¿¶m.¶oWo x ho MbnX Amho Á¶mMm KmVm§H$ 1 Amho.Vo aofr¶ g‘rH$aU Amho. ˶mbm ’$º$ EH$ ~rO AgVo.åhUOoM x + 7 = 12 x = 12 – 7 x = 5
g‘rH$aU (ii) ¿¶m, x (x + 7) = 12 x2 + 7x = 12¶oWo 'x' ho MbnX Amho Á¶mMm KmVm§H$ 2 Amho. ho dJ© g‘rH$aU Amho.Vo H$go gmoS>dmb? dJ© g‘rH$aUmbm {H$Vr ~rOo AmhoV?ho {eH$Uo A˶§V OéarMo Amho H$maU J{UVmÀ¶m BVa emIo‘ܶo BVa {df¶mV Am{U {Z˶ OrdZmVgwÜX
dJ© g‘rH$aUmMo {dñV¥V Ago Cn¶moJ AmhoV.CXmhaUmW© g‘Om EH$m KamVrb d¥Õ {dídñVmZo 300 Mm¡.‘r. joÌ’$imÀ¶m O{‘Zrda EH$ àmW©Zm g^mJ¥h
~m§YʶmMm {ZYm©a Ho$bobm Amho. Á¶mMr bm§~r ˶mÀ¶m é§XrÀ¶m XþßnQ>rnojm 1 ‘rQ>aZo A{YH$ Amho Va ˶mg^mJ¥hmMr bm§~r Am{U é§Xr {H$Vr Agob?
é§Xr 'x' ‘rQ>a ‘mZy. Va ˶mMr bm§~r (2x + 1) ‘rQ>a hmoB©b.˶mMo joÌ’$i = x(2x + 1) Mm¡.‘r. x(2x + 1) = 300 ( {Xbobo)
hr ‘m{hVr AmH¥$VrZo Imbrbà‘mUo Xe©{dbr OmVo.
Amåhr joÌ’$i = x(2x + 1) = (2x2 + x) Mm¡.‘r. 2 1 300x x Mm¡. ‘r.
åhUyZ 2x2 + x = 300. ho dJ© g‘rH$aU Amho. (2x + 1) ‘rQ>a
Imbr H$m§hr A{YH$ boIr {dYmZmÀ¶m ñdê$nmVrb CXmhaUo {Xbobr AmhoV. ˶mMo ê$nm§Va g‘rH$aUmÀ¶ménmV Ho$bo AgVm dJ© g‘rH$aU ñdê$n {‘iVo.
{dYmZm§Mm Aä¶mg H$am. à˶oH$ {dYmZ g‘rH$aUmVrb ñdê$nmV Xe©{dʶmMm à¶ËZ H$am.1. ~|Jiya Am{U åh¡gya ‘Yrb 132 {H$.‘r. A§Va OmʶmgmR>r qH$dm H$mnʶmgmR>r ObX aoëdo hr àdmgr aoëdonojm
1 Vmg H$‘r KoVo. Va ObX aoëdoMm gamgar doJ àdmgr aoëdo nojm 11 {H$.‘r.Xa VmgmZo A{YH$ Agob Va
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Quadratic Equations 193
XmoÝhr aoëd|Mm gamgar doJ {H$Vr?
2. EH$ bmH$S>r H$maImZm EH$m {Xdgmbm H$m§hr bmH$S>r IoiʶmM§ CËnmXZ H$aVmo. à˶oH$ IoiʶmÀ¶m CËnmXZmMrqH$‘V (én¶m‘ܶo) hr V¶ma Ho$boë¶m IoiʶmÀ¶m g§»¶oÀ¶m 55 Zo H$‘r Agë¶mMo AmT>iVo. EH$m {d{eï>{XdgmÀ¶m CËnmXZmMr EHy$U qH$‘V 750 é. hmoVr. Va ˶m {Xder V¶ma Ho$boë¶m Ioiʶm§Mr g§»¶m {H$Vr?
3. g§W nmʶmVrb EH$m ‘moQ>ma ~moQ>rMm doJ 18 {H$.‘r./Vmg AgyZ àdmhmÀ¶m {Xeonojm àdmhmÀ¶m {déÕ {XeoZo
24 {H$.‘r. OmD$Z ˶mM {R>H$mUr naV ¶oʶmgmR>r 1 Vmg OmñV doi bmJVmo. Va àdmhmMm doJ H$mT>m.
4. XmoZ ZimZr EH${ÌVnUo EH$ hm¡X 938
VmgmV ^aVmo. bhmZ ì¶mgmÀ¶m Zimnojm ‘moR>çm ì¶mgmÀ¶m Zimbm
ñdV§ÌnUo Q>mH$s ^aʶmg 10 Vmg H$‘r bmJVmV Va à˶oH$ ZimZo ñdV§ÌnUo Vmo hm¡X {H$Vr doioV ^aob Vo
H$mT>m.
hr CXmhaUo H$er gmoS>dmb?
OmUyZ ¿¶m … ~o~rbmoZrAÝg ¶m§Zr gd© àW‘ dJ© g‘rH$aUo gmoS>{dbr Ago ‘mZbo OmVo. J«rH$ J{UV Vk ¶w³brS>¶mZo ^m¡{‘ÎmrH$ Ñï>rH$moZmMm {dH$mg H$ê$Z bm§~r emoYyZ H$mT>br. ho Xþgao H$m§hr ZgyZ dJ© g‘rH$aUo gmoS>{dʶmMrCH$b Amho.
gm‘mݶ ñdê$nmVrb dJ© g‘rH$aUo gmoS>{dʶmMo lo¶ Zoh‘r àmMrZ J{UV Vk ~«÷Jwá (B.g. 598-665)Am{U lrYamMm¶© (B.g. 1025) ¶m§Zm OmVo. Aa~ J{UV Vk Ab-»dm[aPZr (gw‘mao B.g. 800) ¶mZr gwÕmdJ© g‘rH$aUm§Mm doJdoJù¶m àH$mamZo Aä¶mg Ho$bm Amho.
Aa~ J{UV Vk Ab »dm[aPZr (Al-Khwarizni) (gw‘mao B.g.800) doJdoJù¶m àH$maMr dJ© g‘rH$aUoAä¶mgbr.
"A~«mh‘ ~ma {hæ¶m' hm-Zmgr' ¶mZr B.g. 1145 ‘ܶo ¶wamonmV àH$m{eV Ho$boë¶m ˶m§À¶m "{b~aEå~mS>m}a‘' "Liber embardorum" ¶m nwñVH$mV doJdoJù¶m dJ© g‘rH$aUm§Mr g§nyU© CH$br {Xboë¶m AmhoV.
¶m KQ>H$mV AmnU dJ© g‘rH$aUo, ˶m§Mr ~rOo H$mT>ʶmÀ¶m {d{dY nÕVr Am{U dJ© g‘rH$aUm§Mo Cn¶moJ¶m§Mm gwÕm Aä¶mg H$ê$.
dJ© g‘rH$aUo (Quadratic equation)
KQ>H$ 8 ‘ܶo Amåhr dJ© ~hþnXr~ÕbMm Aä¶mg Ho$bobm Amho Vo AmR>dm.
ax2 + bx + c, ¶m ñdê$nmVrb ~hþnXr OoWo a 0 hr dJ© ~hþnXr Amho qH$dm 2 KmVm§H$mMr MbnX 'x'
‘Yrb amer Amho.
Oa dJ© amer ax2 + bx + c hr eyݶmÀ¶m g‘mZ Ho$br Va Vo dJ© g‘rH$aU ~ZVo.
Imbr H$m§hr boIr {dYmZo {Xbobr AmhoV. Ooìhm Vr dJ© amerV ê$nm§VarV Ho$br Am{U nwT>o ewݶmer g‘mZHo$ë¶mg dJ© g‘rH$aU ~ZVo. CXmhaUm§Mm Aä¶mg H$am.
åhUyZ Vo Ago gwM{dVo H$s Oa P(x) hr dJ© ~hþnXr Amho Va P(x) = 0 ho dJ© g‘rH$aU Amho.
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194 UNIT-9
ho OmUyZ ¿¶m.b°Q>rZ eãX "³dmS´>°Q>‘' ¶m eãXmnmgyZ dJ©hm eãX KoVbobm Amho Á¶mMm AW©Mm¡agmH¥$Vr Agm hmoVmo.
AWm©V P(x) = 0 ¶m ñdê$nmVrb H$moUVohr g‘rH$aU OoWo P(x) hr KmVm§H$ 2 ‘Yrb ~hþnXr AgyZ Vo dJ©g‘rH$aU Amho {OMm à‘m{UV Z‘wZm
ax2 + bx + c = 0, a 0.
dJ © g‘rH$ aU h o 'x' MbnXmM o ax2 + bx + c = 0 ¶m ñdê$nmV rb g‘rH $aU Amh o.O oWo a, b, c, ¶m dmñVd g§»¶m Amh oV Am{U a 0.
dJ© g‘rH$aUm§Mo JwUY‘© AmhoV.
• ho EH$ MbnX AgUmao g‘rH$aU Amho.
• ho EH$ Ago g‘rH$aU Amho H$s Á¶mÀ¶m EH$mM MbnXmMm KmVm§H$ 2 AgVmo.
• dJ© g‘rH$aUmMm à‘m{UV Z‘wZm ax2 + bx + c = 0 hm Amho.
¶oWo x2 Mm ghJwUH$ a Amho.
x Mm ghJwUH$ b Amho.
c ho pñWa nX Amho.
a, b, c ¶m dmñVd g§»¶m AmhoV Am{U a 0.
• MbnXo hr KmVm§H$mÀ¶m CVa˶m H«$‘mV {bhrbobr AmhoV.
dJ©©g‘rH$aUm‘ܶo a 0 ho H$m Amho?
Oa a = 0 AgVmZm dJ© g‘rH$aUmbm H$m¶ hmoB ©b?
dJm©V MMm© H$am.
dJ© g‘rH$aUm‘ܶo a 0 ¶mMr Amåhr MMm© Ho$bobr Amho.
Ooìhm b qH$dm c qH$dm XmoÝhr b Am{U c ho eyݶmerg‘mZ AgVrb Va dJ© g‘rH$aUmÀ¶m à‘m{UV Z‘wݶmMo
A.Z§. boIr {dYmZo dJ© amer dJ© g‘rH$aU
1. EH$ g§»¶m Am{U {VÀ¶m dJm©Mr 5x2 + x 5x2 + x =0nmM nQ> ¶m§Mr ~oarO
2. 12 g|.‘r. bm§~rMr EH$ Vma dmH$dyZH$mQ>H$moZ {ÌH$moUmÀ¶m H$mQ>H$moZ H$aUmè¶m~mOy ~Z{dë¶m AmhoV. ˶mn¡H$s EH$ ~mOyXþgè¶m ~mOynojm 2 g|.‘r. Zo A{YH$ AmhoVa ˶mMo joÌ’$i {H$Vr Agob?
3. {H$H«o$Q> g§KmZo nQ>H$m{dboë¶m Ymdm ¶mn{hë¶m ’$b§XmOmZo nQ>H$m{dboë¶m Ymdm x2 – x – 6 x2 – x – 6 =0Am{U ˶mZo nQ>H$m{dboë¶m Ymdm§À¶m dJm©À¶m’$aH$mnojm 6 Zo H$‘r AmhoV.
1 ( 2)2
x x 21 ( 2 ) 02
x x
21 ( 2 )2
x x 21 ( 2 ) 02
x x
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Quadratic Equations 195
H$m¶ hmoB©b?
Imbr {Xboë¶m gmaUrMo {ZarjU H$am.
A.Z§. b Mr qH$‘V c Mr qH$‘V n[aUm‘ ({ZH$mb)
1. b = 0 c 0 ax2 + c = 0
2. b 0 c = 0 ax2 + bx = 0
3 b = 0 c = 0 ax2 = 0
4. b 0 c 0 ax2 + bx + c = 0
darb gd© KQ>Zo‘ܶo g‘rH$aU ho dJ© g‘rH$aUM amhVo ¶mMo {ZarjU H$am.
gmoS>{dbobr CXmhaUo
CXmhaU 1 … Imbrb dJ© g‘rH$aUo Agë¶mMo Vnmgm.
(i) 2x + x2 + 1 = 0 (ii) 6x3 + x2 = x
(iii)3
( 8) 10 04
x x x (iv) x(x + 1) + 8 = (x + 2) (x – 2)
CH$b(i) 2x + x2 + 1 = 0nXo KmVm§H$mÀ¶m CVa˶m H«$‘mV ‘m§S>m
x2 + 2x + 1 = 0
ho ax2 + bx +c = 0 ¶m à‘m{UV Z‘wݶmV Amho.
{Xbobo g‘rH$aU ho dJ© g‘rH$aU Amho.
(ii) 6x3 + x2 = x
nXm§Mr nwÝhm ‘m§S>Ur Ho$ë¶mg 6x3 + x2 – x = 0 Amåhmbm {‘iVo.
MbnXm§Mm gdm©V ‘moR>m KmVm§H$ 3 Amho.
{Xbobo g‘rH$aU ho dJ© g‘rH$aU Zmhr.
(iii)3 ( 8) 10 04
x x x
g‘rH$aUmbm gaiê$n {Xë¶mZo Amåhmbm {‘iVo.2 23 248 10 0
4 4x x x x
4x2 – 32x + 3x2 – 24x + 40 = 0
x2 – 56x + 40 = 0. ho ax2 + bx + c = 0 ¶m ñdê$nmV Amho.
{Xbobo g‘rH$aU ho dJ© g‘rH$aU Amho.(iv) x (x + 1) + 8 = (x + 2)(x – 2)
g‘rH$aUmbm gaiê$n {Xë¶mZo Amåhmbm {‘iVo.
x2 + x + 8 = x2 – 4 2x 2x + x + 8 + 4 = 0 x + 12= 0
ho ax2 + bx + c = 0 ¶m ñdê$nmV Zmhr.MbnX x ho ’$º$ EH$ KmVm§H$mMo Amho.
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196 UNIT-9
{Xbobo g‘rH$aU ho dJ© g‘rH$aU Zmhr.
ñdmܶm¶ 9.1
1. Imbrb dJ© g‘rH$aUo Agë¶mMo Vnmgm
(i) x2 – x = 0 (ii) x2 = 8 (iii) 2 1 02
x x (iv) 3x – 10 = 0
(v) 2 29 5 04
x x (vi) 225 65
x x (vii) 22 3 0x x (viii)22313
x
(ix) x3 – 10x + 74 = 0 (x) x2 – y 2 = 0
2. Imbrb g‘rH$aUm§Zm gaiê$n Úm Am{U Vr dJ© g‘rH$aUo Agë¶mMo Vnmgm.(i) x(x + 6) = 0 (ii) (x - 4)(2x – 3) = 0
(iii) (x + 2)(x – 7) = 5 (iv) (x + 1)2 = 2(x – 3)(v) (2x – 1)(x – 3) = (x + 5)(x – 1) (vi) (x + 2)3 = 2x(x2 – 1) = (x – 2)3
3. dJ© g‘rH$aUmÀ¶m ñdê$nmV Imbrb Xe©dm.(i) XmoZ H«$‘dma nyUmªH$mMm JwUmH$ma 306 Amho.
(ii) EH$m Am¶VmH$ma CÚmZmMr bm§~r (‘rQ>a‘ܶo) hr é§XrÀ¶m XþßnQ>rÀ¶m 1 ‘rQ>a Zo A{YH$ Amho Am{U˶mMo joÌ’$i 528 Mm¡.‘r. Amho.
(iii) EH$ AmJJmS>r 480 {H$.‘r. A§Va EH$g‘mZ doJmZo OmVo. Oa AmJJmS>rMm doJ 8 {H$.‘r./Vmg Zo H$‘rHo$ë¶mg VoM A§Va OmʶmgmR>r 3 Vmg OmXm doi bmJVmo.
{Xboë¶m gmaUrVrb H$m§hr A{YH$ CXmhaUm§Mo {ZarjU H$am.
A B
x2 = 144 x2 – 7x + 10 = 0
x2 – 81 = 0 17y – y2 + 30 = 0
2y2 = 0 p2 – 20 = – 8p
Amåhmbm Ago {XgyZ ¶oVo H$s• A Am{U B ‘Yrb gd© g‘rH$aUo hr dJ© g‘rH$aUo AmhoV.• A ñV§ mVrb gd© dJ© g‘rH$aUmÀ¶m MbnXmMm KmVm§H$ ’$º$ XmoZ Amho. ˶m§Zm dJ© Ed dJ© g‘rH$aUo Ago åhUVmV.• B ñV§ mVrb gd© dJ© g‘rH$aUmÀ¶m MbnXmMm XmoZ Am{U EH$ Agm XmoÝhr KmVm§H$ Amho ˶m§Zm AdJ© Ed
dJ© g‘rH$aUo Ago åhUVmV.dJ© g‘rH$aUm§M CH$b (gmoB{dUo)…x2 – 25 = 0 ¶m dJ© Ed dJ© g‘rH$aUmMm {dMma H$am.AmnU 'x' Mr dmñVd qH$‘V KoD$ Am{U g‘rH$aUm‘ܶo ‘m§Sy>.
‘mZy x = 1 ‘mZy x = 5S>mdr ~mOy = x2 – 25 = 12 – 25 = – 24 S>mdr ~mOy = x2 – 25 = 52 – 25 = 0
LHS RHS S>mdr ~mOy = COdr ~mOy
‘mZy x = – 2 ‘mZy x = – 5
S>mdr ~mOy = x2 – 25 =(–2)2 – 25 = – 21 S>mdr ~mOy = x2 – 25 = (–5)2 – 25 = 0
S>mdr ~mOy COdr ~mOy S>mdr ~mOy = COdr ~mOy
ñV§ A Am{U B ‘Yrbg‘rH$aUm§Mr VwbZm H$am.
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Quadratic Equations 197
ho 'x' À¶m doJdoJù¶m qH$‘VrgmR>r à¶ËZ H$am.
Amåhmbm Ago {XgyZ ¶oVo H$s x = 5 Am{U x = – 5 ¶m 'x' À¶m ’$º$ XmoZ qH$‘VrgmR>r S>mdr ~mOy = COdr ~mOy Amho.
Amåhr Ago gm§Jy H$s +5 Am{U –5 ho x2 – 25 = 0 ¶m g‘rH$aUmMr nyV©Vm H$aVo.
+5 Am{U –5 Zm dJ© g‘rH$aUmMr ~rOo Ago åhUVmV.
+5 Am{U –5 ¶mZm x2 – 25 ¶m ~hþnXtMr eyݶo Ago åhUVmV.
dJ© g‘rH$aUmMr ~rOo g‘rH$aUmMo g‘mYmZ H$aVmV. ¶mMmM AW© S>mdr ~mOy = COdr ~mOy.
darb MMm© hr AdJ© Ed dJ© g‘rH$aUm§Zm gwÕm bmJy nS>Vo.
x2 – 3x – 10 = 0 ¶m AdJ© Ed dJ© g‘rH$aUmMm {dMma H$am.
‘mZy x = 1 ‘mZy x = –3
S>mdr ~mOy LHS= x2 – 3x – 10 = 12 – 3(1) – 10 S>mdr ~mOy = x2 – 3x – 10 = (–3)2 – 3(–3) –10
= – 12 = 8
S>mdr ~mOy COdr ~mOy S>mdr ~mOy COdr ~mOy
‘mZy x = 5 ‘mZy x = – 2
S>mdr ~mOy = x2 – 3x – 10 = 52 – 3(5) – 10 S>mdr ~mOy = x2 – 3x – 10 = (–2)2 – 3(–2) – 10
= 0 = 0
S>mdr ~mOy = COdr ~mOy S>mdr ~mOy = COdr ~mOy
Amåhmbm Ago {XgyZ ¶oVo H$s x2 – 3x – 10 = 0 ¶m dJ© g‘rH$aUmMr nyV©Vm ’$º$ x = 5 Am{U x = – 2
¶m qH$‘VrgmR>r hmoVo.
5 Am{U –2 hr x2 – 3x – 10 = 0 ¶m dJ© g‘rH$aUmMr ~rOo AmhoV.
5 Am{U –2 hr x2 – 3x – 10 = 0 ¶m dJ© ~hþnXtMr eyݶo AmhoV.
gm‘mݶnUo ax2 + bx + c = 0 ¶m dJ© g‘rH$aUmMr dmñVd g§»¶m 'k' ho ~rO Amho. a 0 Oaak2 + bk + c = 0.
Amåhr Ago gwÕm gm§Jy H$s x = k hm dJ© g‘rH$aUmMo CH$b Amho, qH$dm k dJ© g‘rH$aUmMr nyV©Vm H$aVo.
ax2 + bx + c ¶m dJ© ~hþnXrMr eyݶo Am{U ax2 + bx + c ¶m dJ© g‘rH$aUmMr ~rOo g‘mZ AgVmV hobjmV R>odm.
Amåhmbm ‘m{hV Amho H$s dJ© ~hþnXrbm OmñVrV OmñV XmoZ eyݶo AgVmV.
H$moU˶mhr dJ© g‘rH$aUmbm OmñVrV OmñV XmoZ ~rOo AgVmV.
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198 UNIT-9
dJ© g‘rH$aU gmoS>{dUo åhUOo dJ© g‘rH$aUmMr ~rOo H$mT>Uo hmo¶. dJ© g‘rH$aUm‘ܶo qH$‘Vr ‘m§Sy>Z~rOm§Mm nS>Vmim H$aVm ¶oVmo Am{U g‘rH$aUmMr nyV©Vm hmoVo H$s Zmhr ho VnmgVm ¶oVo. ~rOo hr dJ©g‘rH$aUmMmCH$b g§M ~Z{dVmV.
dJ© Ed dJ© g‘rH$aUmMr CH$b … (Solution of a pure quadratic equation)
1. x2 – 225 = 0 gmoS>dm.
CH$b … x2 – 225 = 0 x2 = 225 x = 225 (XmoÝhr ~mOy§Mo dJ©‘yi H$mT>ë¶mZo)
x = 15 x = +15 qH$dm x = – 15
2. gmoS>dm … 143 = t2 – 1
CH$b … 143 = t2 – 1
g‘rH$aU à‘m{UV Z‘wݶmV nwÝhm {bhm.
t2 = 143 + 1 t2 = 144 t = + 144 t = +12
t = +12 qH$dm t = – 12
3. Oa V = r2h Va 'r' H$Vm© H$am Am{U Ooìhm V = 176 Am{U h = 14 Va 'r' Mr qH$‘V H$mT>m.
CH$b … {Xbobo V = r2h
r2h = V r2 =Vh
r =Vh
Oa V = 176 Am{U h = 14 Amåhmbm {‘iVo
r =176
14(qH$‘Vr ‘m§Sy>Z) r =
176 7 17622 14
8 4
7
22 142 4 = 2
r = +2 qH$dm r = – 2
4. ídoVmZo Mm¡ag AmH$mamMr 625 Mm¡.‘r. O{‘Z {dH$V KoVbr Amho. {Vbm ˶m O{‘Zrbm H$mQ>oar VmaoMoHw§$nU Kmbm¶Mo Amho. g^modVmbr 4 ’o$ao KmbʶmgmR>r {H$Vr bm§~rMr Vma bmJob?
CH$b … Mm¡agmMr bm§~r x ‘rQ>a ‘mZy.
Mm¡agmMo joÌ’$i = x2
625 = x2 x2 = 625 x = 625 = 25 x =+25 qH$dm x = – 25
bm§~r F$U AgV Zmhr Amåhr x = +25 KoD$.
Mm¡agmÀ¶m EH$m ~mOyMr bm§~r = +25 ‘rQ>a
Mm¡agmMr n[a{‘Vr = 4x ‘rQ>a
Mma ’o$è¶mgmR>r bmJUmar Vma = 4 × 4x = 16x ‘rQ>a
AmR>dmYZ dmñVd g§»¶mZm XmoZ ~rOo AgVmV.EH$ YZ Am{U Xþgao F$U AgVo.
1 1 & 0 0Am{U1 1 & 0 0
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Quadratic Equations 199
bmJUmè¶m VmaoMr bm§~r = 16 × 25 = 400 ‘rQ>a
ñdmܶm¶ 9.2
1. dJ© Ed dJ© g‘rH$aU Am{U AdJ© Ed dJ© g‘rH$aUm‘ܶo Imbrb g‘rH$aUmMo dJuH$aU H$am.(i) x2 = 100 (ii) x2 + 6 = 6 (iii) p(p – 3) = 1 (iv) x2 + 3 = 2x
(v)(x + 9)(x – 9) (vi) 2x2 = 72 (vii) x2 – x = 0 (viii) 7x =35x
(ix)1 5xx
(x)814xx
(xi) (2x – 5) 2 = 81 (xii)2( 4) 2
18 9x
2. dJ© g‘rH$aUo gmoS>dm.
(i) x2 – 196 = 0 (ii) 5x2 = 625 (iii) x2 – 1 = 101 (iv) 7x =647x
(v) (x + 8)2 – 5 = 31 (vi)2 3 17
2 4 4x
(vii) –4x2 + 324 = 0 (viii) –37.5x2 = –37.5
3. Imbrb à˶oH$mgmR>r {Xboë¶m 'x' À¶m qH$‘Vr dJ© g‘rH$aUmMr CH$b Amho qH$dm Zmhr Vo R>adm.
(i) x2 + 14x + 13 = 0 ; x = –1, x = – 13 (ii) 7x2 – 12x = 0 ; x =13
(iii) 2m2 – 6m + 3 = 0 ; m=12
(iv) 2 2 4 0y y ; y = 2 2
(v)1
2 2x
x ; x = 2 Am{U x = 1 (vi) 6x2 – x – 2 = 0 ; x =12 Am{U x =
23
4. (i) Oa A = r2 Va 'r' H$Vm© H$am Am{U Oa A = 77 Am{U =227
Va 'r' Mr qH$‘V H$mT>m.
(ii) Oa r2 = l2 + d2 Va 'd' H$Vm© H$am Am{U Oa r = 5 Am{U l = 4 Va 'd' Mr qH$‘V H$mT>m.
(iii) Oa c2 = a2 + b2 Va 'b' H$Vm© H$am Am{U Oa a = 8 Am{U c = 17 Va 'b' Mr qH$‘V H$mT>m.
(iv) Oa A =23
4a Va 'a' H$Vm© H$am Am{U Oa A = 16 3 Va 'a' Mr qH$‘V H$mT>m.
(v) Oa k =12
mv2 Va 'v' H$Vm© H$am Am{U Oa k = 100 Am{U m = 2 Va 'v' Mr qH$‘V H$mT>m.
(vi) Oa v2 = u2 + 2as Va 'v' H$Vm© H$am Am{U Oa u = 0, a = 2, s = 100 Va 'v' Mr qH$‘V H$mT>m.
AdJ© Ed dJ© g‘rH$aUmMr CH$b …
Amåhmbm ‘mhrV Amho H$s AdJ© Ed dJ© g‘rH$aUmMm gm‘mݶ Z‘wZm ax2 + bx + c = 0 Amho. a 0, ho g‘rH$aU
ax2 + b = 0, ax2 + c = 0 Am{U ax2 = 0 Aem doJdoJù¶m ñdê$nmV XoIrb AmT>iVo.
ax2 = 0 Am{U ax2 + c = 0 hr dJ© Ed dJ© g‘rH$aUo AmhoV Am{U ‘mJrb ^mJmV Vr gmoS>{dʶmMr nÕV
Amåhr {eH$bobr (Aä¶mgbobr) Amho.
AdJ© Ed dJ© g‘rH$aU H$go gmoS>dmdo?
ax2 + bx + c = 0 qH$dm ax2 + b = 0 øm ˶m§À¶m Z‘wݶmda AmYmarV AdJ© Ed dJ© g‘rH$aUo
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200 UNIT-9
gmoS>{dʶmÀ¶m nwîH$i nÕVr AmhoV.
˶mMm AmnU Aä¶mg H$é¶m.
(A) Ad¶drH$aU nÕVrZo dJ© g‘rH$aUmMr CH$b …dJ© ~hþnXrMo Ad¶d ˶m§À¶m ‘Yë¶m nXmMr ’$moS> H$ê$Z H$mT>Uo ho Amåhr {eH$bobo Amho. ¶m kmZmMm
Cn¶moJ H$ê$Z Amåhr dJ© g‘rH$aUmMr ~rOo H$mTy> eH$Vmo.
Ooìhm dJ© g‘rH$aUmMo XmoZ aofr¶ Ad¶d nmS>bo OmVmV Voìhm Ad¶drH$aU nÕV dmnaVmV. Ad¶drH$aUmZ§Va˶mÀ¶m XmoZ aofr¶ Ad¶dmV dJ© g‘rH$aU 춺$ H$aVmV Am{U Vo eyݶmÀ¶m g‘mZ ‘m§S>VmV.
åhUOoM ax2 + bx + c = 0 (x m) (x n) = 0Z§Va Amåhr eyݶ JwUmH$ma {Z¶‘ bmJy H$aVmo Am{U à˶oH$ Ad¶d eyݶmÀ¶m g‘mZ ‘m§S>Vmo Am{U
A춺$mgmR>r gmoS>{dVmo.x m = 0 x = mx n = 0 x = n
åhUyZ ax2 + bx + c = 0 ¶m dJ© g‘rH$aUmMr ~rOo mAm{U n AmhoV.
x2 + 5x + 6 = 0 ho dJ© g‘rH$aU {dMmamV ¿¶m.‘Ybo nX 5x Am{U ˶mMm ghJwUH$ 5 Amho.AmnU 5 Mr ’$moS> Aer H$ê$ H$s m + n = 5 Am{U mn = 6 hmoB©b.x2 + 3x + 2x + 6 = 0 x(x + 3) + 2(x + 3) = 0 (x + 3)(x + 2) = 0
AmVm x2 + 5x + 6 = 0 Mo XmoZ aofr¶ Ad¶d (x + 3) Am{U (x + 2) ho nmS>m.eyݶ JwUmH$ma {Z¶‘mMm Cn¶moJ Ho$ë¶mZo Amåhmbm (x + 3)(x + 2) = 0 {‘iVo.x + 3= 0 qH$dm x + 2 = 0 x + 3= 0 ho XoVo x = – 3 x + 2 = 0 ho XoVo x = – 2
CH$b g§M {–3, –2} Amho.Aem[aVrZo -3 Am{U -2 hr XmoZ ~rOo x2 + 5x + 6 = 0 ¶m dJ© g‘rH$aUmMr AmhoV.~¡{OH$ ’$aí¶m§Mm Cn¶moJ H$ê$Z ho AmH¥$VrÛmao gwÕm Imbrbà‘mUo Xe©{dVm ¶oVo.
x
x
x2 + x x x x x x x x x x +
1 1 1 1 1
+ 5 + 6x x2
11 11
11 11
11 11
11 11
11 11
11 11
gd© ’$aí¶m§Mr ‘m§S>Ur Ho$br AgVm Amåhmbm AmH¥$Vr {‘iVo.
{ZarjU H$am H$s bm§~r = x + 3 Am{U é§Xr = x + 2 Am{U ˶mMojoÌ’$i x2 + 5x + 6 Amho.
Am¶VmMo joÌ’$i A = l × b
x2 + 5x + 6 = (x + 3)(x + 2)
¶mdê$Z Amåhr Agm {ZîH$f© H$mT>Vmo H$s
eyݶ JwUmH$ma {Z¶‘a Am{U b øm H$moU˶mhr XmoZ dmñVd g§»¶mqH$dm Ad¶d AmhoV. Oa a × b = 0 Va a= 0 qH$dm b = 0 XmoÝhr a = 0 Am{U b = 0
x x x x x
x
x2
x x 1 1 1
1 1 11 1 1
11
( + 2)x
( + 3)x
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Quadratic Equations 201
Oa dJ© ~hþnXr ax2 + bx + c hr Mm¡ag qH$dm Am¶VmMo joÌ’$i Xe©{dV Agob Va ˶mMo XmoZ Ad¶d hobm§~r Am{U é§Xr Xe©{dVmV.
Ad¶drH$aU nÕVrZo dJ© g‘rH$aUmdarb gmoS>{dboë¶m CXmhaUm§Mm Aä¶mg H$am.
gmoS>{dbobr CXmhaUo
CXmhaU 1) gmoS>dm x2 – 3x + 2 = 0CH$b … {Xbobo x2 – 3x + 2 = 0
x2 – 2x – 1x + 2 = 0 (amerMo n¥W…H$aU)x(x – 2) –1(x – 2) = 0 (g‘mB©H$ Ad¶d KoD$Z) (x – 2)(x – 1) = 0 (g‘mB©H$ Ad¶d KoD$Z)
x – 2 = 0 or x – 1= 0 (à˶oH$ Ad¶d eyݶmÀ¶m g‘mZ ‘m§S>m)x = + 2 qH$dm x = 1
–2 Am{U + 1 hr (x2 – 3x + 2) Mr ~rOo AmhoV.CXmhaU 2) gmoS>dm … 6x2 – x – 2 = 0
CH$b … {Xbobo … 6x2 – x – 2 = 0
6x2 + 3x – 4x – 2 = 0 3x(2x + 1) – 2(2x + 1) = 0 (2x + 1)(3x – 2) = 0
2x + 1 = 0 qH$dm 3x – 2 = 0 2x = – 1 qH$dm 3x = 2 x =12 qH$dm x =
231
2Am{U
23
hr 6x2 – x – 2 = 0 Mr ~rOo AmhoV.
CXmhaU 3) 3x2 – 2 6x + 2 = 0 ¶m dJ© g‘rH$aUmMr ~rOo H$mT>m.
CH$b … {Xbobo … 23 2 6 2x x = 0
23 6 6 2x x x = 0 3 3 2 2 3 2x x x = 0
3 2 3 2x x = 0 3 2 0x 3 2x = 0
3x = 2 qH$dm 3x = 2 , x =23
, x =23
åhUyZ à˶oH$ nwZamd¥ÎmrV Ad¶dmgmR>r 3 2x EH$ ¶mà‘mUo ~rOm§Mr XmoZXm nwZamd¥Îmr hmoVo.23 2 6 2 0x x Mr XmoZ g‘mZ ~rOo 2 2,
3 3hr AmhoV.
CXmhaU 4) 24 10x = 3 – 4x
CH$b … {Xbobo … 24 10x = 3 – 4 x
XmoÝhr ~mOy§Mm dJ© Ho$ë¶mg Amåhmbm {‘iVo.2
24 10x = (3 – 4x)2 24 – 10x = 9 – 24x + 16x2 16x2 – 24x + 10x + 9 – 24 = 0
16x2 – 24x + 10x – 15 = 0 8x(2x – 3) + 5(2x – 3) = 0
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202 UNIT-9
(2x – 3)(8x + 5) = 0 2x – 3 = 0 qH$dm 8x + 5 = 0
2x = 3 qH$dm 8x = – 5, x =32
x =58
24 10x = 3 – 4x Mr ~rOo32
Am{U58
hr AmhoV.
Ad¶drH$aU nÕVrZo dJ© g‘rH$aUmMr ~rOo H$mT>ʶmÀ¶m nm¶è¶m.1. {Xbobo g‘rH$aU dJ© g‘rH$aUmÀ¶m à‘m{UV Z‘wݶmV ax2 + bx + c = 0 ‘ܶo {bhm.2. dJ© amer ˶mÀ¶m ‘Yë¶m nXmMr ’$moS> nmSy>Z (S>mdr ~mOy) ‘m§S>m.3. g‘mB©H$ Ad¶d ¿¶m Am{U XmoZ aofr¶ Ad¶d {‘idm.4. à˶oH$ Ad¶d eyݶmMr g‘mZ ‘m§S>m.
5. à˶oH$ aofr¶ g‘rH$aUmbm gaiê$n Úm Am{U A춺$mMr qH$‘V H$mT>m.
ñdmܶm¶ 9.3
Ad¶drH$aU nÕVrZo dJ© g‘rH$aU gmoS>dm.
1. x2 + 15x + 50 = 0 2 .6 – p2 = p 3. 100x2 – 20x + 1 = 0
4. 22 7 5 2 0x x 5. x2 + 4kx + 4k2 = 0 6.7 6mm
7. 0.2t2 – 0.04 t = 0.03 8. 25 2 3 5x x 9.1 34
1 15x x
x x10.
1 3 132 4 3
x xx x
11. a2b2x2–(a2+b2)x +1= 0 12. (2x – 3) = 22 2 21x x
nyU© dJ© nÕVrZo nyU© H$aUo …
x2 + 5x + 5 = 0 ¶m dJ© g‘rH$aUmMm AmnU {dMma H$é.
¶oWo 5x ¶m ‘Yë¶m nXmMr m + n = 5 Am{U mn = 5 Aer ’$moS> H$aVm ¶oV Zmhr. ¶mMmM AW© AgmH$s XmoZ Ad¶dmÀ¶m JwUmH$mamV g‘rH$aUmMr ‘m§S>Ur AmåhmbmH$aVm ¶oV Zmhr. Am{U Ad¶drH$aU nÕVrZo Vo gmoS>{dVm ¶oVZmhr. dJ© g‘rH$aUo gmoS>{dʶmgmR>r Ad¶drH$aU nÕVrbm hr‘¶m©Xm Amho. ‘Yë¶m nXmMr ’$moS> H$aUo Am{U {Xboë¶m dJ©~hþnXrMo Ad¶d nmS>Uo ho Ooìhm e³¶ Amho ’$º$ VoìhmM hrnÕV dmnaVmV.
Va OoWo dJ© ~hþnXrMo Ad¶d nmS>Vm ¶oV ZmhrV Vr dJ©g‘rH$aUo H$er gmoS>dmdrVmV?
¶mMo Ad¶d H$m nmS>Vm ¶oV ZmhrV ho OmUyZ KoʶmgmR>r Amåhr {Xbobo dJ© g‘rH$aU x2 + 5x + 5= 0 hoAmH¥$VrÛmao gwÕm Xe©dy eH$Vmo.
x2 + 5x + 5 x x x
x2
x x 1 1 1
1 1
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Quadratic Equations 203
Imbrb AmH¥$VrMo {ZarjU H$am.
Amåhmbm Ago {XgyZ ¶oVo H$s x2 + 5x + 5 Xe©{dUmar AmH¥$Vr hr nyU© Mm¡ag qH$dm Am¶V Zmhr. ¶mMm AW©Agm H$s Oa AmH¥$Vr nyU© Mm¡ag qH$dm Am¶V Ho$br Va Vo Amåhr gmoS>dy eH$Vmo.Z§Va AmnU Ad¶d nÜXVrZ gmoS>dyeH$Vmo.
Ago nyU© Mm¡ag qH$dm Am¶V ¶m§Mo nyU© Mm¡ag qH$dm nyU© Am¶V H$aVmZm ˶m‘ܶo H$m§hr ^mJ {‘i{dboOmVmV. Á¶m nÜXVr‘ܶo H$m§hr ^mJ {‘idyZ nyU© Mm¡ag qH$dm nyU© Am¶Vm ~Z{dbo OmVmV. ˶mbm nyU© dJ© nÜVåhUVmV.
B. dJ© g‘rH$aU nyU© dJ© nÕVrZo gmoS>{dUo …
da MMm© Ho$boë¶m x2 + 5x + 5 ¶m g‘rH$aUmMm {dMma H$am. AmH¥$Vrdê$ZAmåhmbm Ago {XgyZ ¶oVo H$s x2 + 5x + 5 ho 12 qH$dm nyU© Mm¡ag qH$dm Am¶V V¶mahmoʶmgmR>r 1 Zo H$‘r Amho.
Xþgè¶m eãXmV {(x2 + 5x + 5) + 1} Zo nyU© Mm¡ag V¶ma hmoB©b Am{U ˶mMo Ad¶dnmS>Vm ¶oVmV.
åhUOoM x2 + 5x + 5 + 1 = 0 x2 + 5x + 6 = 0 (x + 3)(x + 2) = 0
x = –3 qH$dm x = –2
åhUyZ x2 + 5 x – 5 ho nyU© Mm¡ag Xe©{dV Zmhr.
nyU© Mm¡ag ~Z{dʶmgmR>r {Xboë¶m g‘rH$aUm‘ܶo H$m¶ {‘idmdo qH$dm dOm H$amdo?
nyU© Mm¡ag Xe©{dUmao {Z˶ g‘rH$aU AmR>dm.
a2 + 2ab + b2 = (a + b)(a + b) ho Amåhmbm ‘m{hVAmho.Oa Vo (a2 + 2ab + b2) ¶m ñdénmV Agob Va ho AgoXe©{dVo H$s H$moU˶mhr dJ© ~hþnXrMo aofr¶ Ad¶d nmS>Vm¶oVmV.
a2 + 2ab + b2 ‘ܶo ‘Ybo nX2ab Amho OoWo 2 ho pñWam§H$ Amho.a ho n{hë¶m nXmMo dJ©‘yi Amho.b ho eodQ>À¶m nXmMo dJ©‘yi Amho.AmVm x2 + 5x – 5 = 0 ¿¶m. ‘Ybo nX 4x Amho.5x Mr VwbZm 2ab er H$am.
2ab =5x 2 × x × b = 5x
b =52
xx = 2
x ¶m ghJwUH$mÀ¶m {Zå‘o b =52 Amho ¶mMo {ZarjU H$am.
x x x x2
x x 1 1 1
1 1 1
a2 + 2ab + b2
a2 ab
ab
a
b
b
b
a
a
a
(+
)a
b
( + )a b
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204 UNIT-9
b Mm dJ© Ho$ë¶mZo, b2 =52
2( ) =254
dJ© g‘rH$aU x2 + 5 x – 5 = 0 À¶m g‘rH$aUmÀ¶m XmoÝhr ~mOybm254 {‘idyZ qH$dm S>mì¶m ~mOyV
254 {‘idyZ nyU© dJm©V énm§Va Ho$bo OmVo. g‘rH$aUmMr ‘yi qH$‘V VrM amhrb Aem[aVrZo Amåhr XmoÝhr
~mOybm {‘i{dVmo.
nwÝhm x2 + 5 x + 5 = 0 ho g‘rH$aU ¿¶m. x2 + 5 x = 5
x2 +5 x +254 =– 5 +
254
(x +52 )
2 =
54
5 52 2
+ = =x
5 52 2 + =x + Am{U 5 5
2 2 + =x -5 52 2 =x - 5 5
2 2 =x --( )5 5
2 =x - ( )5 52 + =x -
5 52- Am{U ( )5 5
2 +- hr x2 + 5 x + 5 = 0 ¶m g‘rH$aUmMr ~rOo AmhoV.
åhUyZ Amåhr x2 + 5 x + 5 = 0 ho g‘rH$aU nyU© dJ© nÜXVrZo gmoS>{dbo Amho. ¶mbm nyU© dJ© H$ê$Z
gm oS{dUo Ago åhUVmV.
ñnîQ>rH$aUmË‘H$ CXmhaUo
CXmhaU 1) nyU© dJ© H$ê$Z x2 + 6x – 7 = 0 ho dJ© g‘rH$aU gmoS>dm.
CH$b … {Xbobo … x2 + 6x – 7 = 0 2 × a × b = 6x
x2 + 6x + 9 – 9 – 7 = 0 2 × x × b = 6x ( a = x)
x2 + 3x + 3x + 9 = + 16 b =62
xx
x(x + 3) + 3(x + 3) = 16 b = 3
(x + 3)(x + 3) = 16 b2 = 9
(x + 3)2 = 42 XmoÝhr ~mOyMo dJ©‘yi KoVë¶mg
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Quadratic Equations 205
x + 3 = ± 4 (x À¶m ghJwUH$mÀ¶m {Zå‘o =62 b = 3)
Oa x + 3 = 4 x + 3 = – 4 x = 4 – 3 x = – 4 – 3 x = 1 x = – 7
1 Am{U –7 hr x2 + 6x – 7 = 0 Mr ~rOo AmhoV.
CXmhaU 2) nyU© dJ© nÕVrZo 3x2 – 5x + 2 = 0 gmoS>dm.
CH$b … {Xbobo … 3x2 – 5x + 2 = 0
¶oWo x2 Mm ghJwUH$ 3 Amho Am{U Vmo nyU© dJ© Zmhr. Aer dJ© g‘rH$aUo XmoZ àH$mao gmoS>{dVm ¶oVmV. AmnU˶m XmoÝhr àH$mamZo gmoS>dy.
(i) g§nyU© g‘rH$aUmbm 3 Zo JwU.
(3x2 – 5x + 2 = 0) × 3 9x2 – 15x + 6 = 0
AmVm x À¶m ghJwUH$mMo {Zå‘o52 Amho. b =
52 Am{U b2 =
252
åhUyZ 9x2 – 15x +2 25 5 6
2 2= 0 (3x)2 – 15x +
252
=25
2 – 6
2532
x =25 64
=14
3x –52
=12
(XmoÝhr ~mOy§Mo dJ©‘yi KoVë¶mZo)
3x –52 = +
12 qH$dm 3x –
52 = –
12
3x =12
+52
3x =52
–12
3x = 62
= 3 3x =42
= 2
x = 1 x =23
(ii) g§nyU© g‘rH$aUmbm 3 Zo ^mJm.
(3x2 – 5x + 2 = 0) 3 x2 –5 23 3
x = 0
AmVm nyduà‘mUoM AmnU nwT>o OmD$2
21 5 5 52 3 6 6
b b
åhUyZ2 2
2 5 5 5 23 6 6 3
x x = 025
6x =
25 26 3
256
x =25 2 136 3 36
XmoÝhr ~mOy§Mo dJ© ‘yi KoD$.
56
x =16
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206 UNIT-9
56
x = +16
, x =5 16 6
=6 16
x = 1 qH$dm
x –56 = –
16 , x =
5 1 4 26 6 6 3 x =
23
1 Am{U23
hr 3x2 – 5x + 2 = 0 ¶m dJ© g‘rH$aUmMr ~rOo AmhoV.
ñdmܶm¶ 9.4
Imbrb dJ© g‘rH$aUo nyU© dJ© H$ê$Z gmoS>dm.
(i) 4x2 – 20x + 9 = 0 (ii) 4x2 + x – 5 = 0 (iii) 2x2 + 5x – 3 = 0(iv) x2 +16x – 9 = 0 (v) x2 – 3x + 1 =0 (vi) t2 + 3t = 7
J{UVmV {heo~ Am{U g‘ñ¶m gmoS>{dUo ho gyÌm§À¶m Cn¶moJmZo gmono Pmbobo Amho. ho Amåhmbm ‘mhrV Amho.˶mMà‘mUo gwÌmMm Cn¶moJ H$ê$Z dJ© g‘rH$aUo gmo߶m [aVrZo gmoS>{dVm ¶oVmV. dJ© gyÌ Oo ˶mMr ~rOoH$mT>ʶmgmR>r A{Ve¶ Cn¶wº$ Amho Vo nyU© dJ© nÕVrMm Cn¶moJ H$ê$Z {gÕ H$aVm ¶oVo. AmnU dJ© gyÌ {gÕ H$ê$.Am{U dJ© g‘rH$aUm§Mr ~rOo H$mT>ʶmgmR>r ˶mMm H$gm dmna H$amdm ho {eHy$¶m.
C) gyÌ nÕVrZo dJ© g‘rH$aUmMr CH$b …
dJ© g‘rH$aU ax2 + bx + c = 0, a 0 ho {dMmamV ¿¶m.
g‘rH$aUmbm a Zo ^mJm (x2 Mm ghJwUH$)b cx xa a
= 0
x À¶m ghJwUH$mÀ¶m {Zå‘o H$mT>m Am{U ˶mMm dJ© H$am.
12
ba = 2
ba
2
2ba
=2
24ba
ca Mo COì¶m ~mOyg njm§Va H$am 2 bx x
a = –ca
2
2ba g‘rH$aUmÀ¶m XmoÝhr ~mOyg {‘idm.
2 22
2 2b b b cx xa a a a
S>mì¶m ~mOyMo Ad¶d nmS>m Am{U COì¶m ~mOybm gaiê$n Úm.2 2 2
2 2
42 4 4b b c b acxa a a a
g‘rH$aUmÀ¶m XmoÝhr ~mOyMo dJ©‘yi ¿¶m.
2 2
2
4 42 4 2b b ac b acxa a a
2 42 2b b acxa a
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Quadratic Equations 207
2 42
b b acxa
ax2 + bx + c = 0 ¶m dJ© g‘rH$aUmMr ~rOo
x =2 4
2b b ac
aAm{U x =
2 42
b b aca
AmhoV.
x =2 4
2b b ac
a¶mbm dJ© gyÌ Ago åhUVmV.
darb {gÕVo‘ܶo nyU© dJ© Zgbobm x2 Mm ghJwUH$ g‘rH$aUmbm 'a' Zo ^mJyZ Amåhr H$mTy>Z Q>mH$bm.VWm{n g‘rH$aUmbm '4a' Zo JwUyZ gwÕm gmoS>{dVm ¶oVo. ¶m nÕVrbm "lrYamMm¶m©Mr nÕV' Ago åhUVmV.lrYamMm¶© (1025 B.g.) ¶mZm nyU© dJ© nÕVrZo dJ© g‘rH$aUmMo gyÌ {gÕ H$aʶmMo lo¶ OmVo. àmMrZ ^maVr¶J{UV Vk lrYamMm¶© ¶mZr {dH$grV Ho$boë¶m dJ© gyÌ {gÕVoMm Aä¶mg H$am.
dJ© g‘rH$aUmÀ¶m à‘m{UV Z‘wݶmMm ax2 + bx + c = 0, a 0 Mm {dMma H$am.
XmoÝhr ~mOybm 4a Zo JwUm
{(ax2 + bx + c) = 0} × 4a 4a2x2 + 4abx + 4ac = 0 4a2x2 + 4abx = –4ac
XmoÝhr ~mOybm b2 {‘idm.
4a2x2 + 4abx + b2 = b2 – 4ac (2ax)2 + 4abx + b2 = b2 – 4ac (2ax + b)2 = b2 – 4ac
2ax + b = 2 4b ac 2ax = 2 4b b ac x = 2 4b b ac
x =2 4
2b b ac
aAm{U x =
2 42
b b aca
gmoS>{dbobr CXmhaUo
CXmhaU 1) x2 – 7x + 12 = 0 gyÌ nÕVrZo gmoS>dm.
CH$b … {Xbobo x2 – 7x + 12 = 0
ho ax2 + bx + c = 0 ¶m Z‘wݶmV Amho. OoWo a =1, b = –7 Am{U c = 12
dJ© gyÌ x =2 4
2b b ac
aAmho.
qH$‘Vr ‘m§S>ë¶mZo Amåhmbm {‘iVo.
x =2( 7) ( 7) 4 1 12
2 1 x =
7 49 482
x =7 1
2x =
7 12
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208 UNIT-9
Oa x =7 1 8
2 2 = 4 x =
7 1 62 2
= 3
4 Am{U 3 hr x2 – 7x + 12 = 0 Mr ~rOo AmhoV.
CXmhaU 2) m2 = 2 + 2m gmoS>dm
CH$b … {Xbobo m2 = 2 + 2m
g‘rH$aU nwÝhm à‘m{UV Z‘wݶmV åhUOoM m2 – 2m – 2 = 0 ‘m§S>m.
ho ax2 + bx + c = 0 ¶m ñdénmV Amho. OoWo a = 1, b = –2, c = –2
x =2 4
2b b ac
a(dJ© gyÌ) x =
2( 2) ( 2) 4(1)( 2)2 1
x =2 4 8
2 x =
2 122
x = 2 2 3 2 1 3 1 32 2
x = 1 3 Am{U 1 3 hr dJ© g‘rH$aU m2 = 2 + 2m Mr ~rOo AmhoV.
CXmhaU 3) gmoS>dm 1 2 41 2 4x x x
CH$b … {Xbobo1 2 4
1 2 4x x x
g‘rH$aUmbm gaiê$n Úm.
11x
=4 2
4 2x x1
1x=
2 124 2x x
11x
=2( 2) 1( 4)2
( 4)( 2)x xx x
11x
=2 4 42( 4)( 2)x xx x
11x =
2( 4)( 2)
xx x (x + 4)(x + 2)= 2x(x + 1) x2 + 6x + 8 = 2x2 + 2x
x2 – 4x – 8 = 0 ho dJ© g‘rH$aU Amho.
¶oWo a = 1, b = –4, c = –8
x =2 4
2b b ac
ax =
2( 4) ( 4) 4 (1)( 8)2(1)
x =4 48
2
x =4 4 3
2 = 4 1 3 2 1 3
2
x = 2 1 3 Am{U x = 2 1 3
2 1 3 Am{U 2 1 3 hr {Xboë¶m dJ© g‘rH$aUmMr ~rOo AmhoV.
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Quadratic Equations 209
CXmhaU 4) x2 + x – (a + 2)(a + 1) = 0 gyÌmMm Cn¶moJ H$ê$Z gmoS>dm.
CH$b … {Xbobo x2 + x – (a + 2)(a + 1) = 0 ¶oWo a = 1, b = 1, c = –(a + 2)(a + 1)
x =2 4
2b b ac
a=
21 1 4 ( 2)( 1)2(1)
a a =
21 1 4 ( 3 2)2a a
x =21 1 4 12 8
2a a
=21 4 12 92
a a =
21 (2 3)2a
=1 (2 3)
2a
x =1 2 3
2a
Am{U x =1 2 3
2a
x =2 2
2a
Am{U x =2 4
2a
x = a + 1 x = –(a + 2)
x2 + x – (a + 2)(a + 1)= 0 Mr ~rOo (a + 2) Am{U –(a + 2) hr AmhoV.
dJ© gyÌmMm Cn¶moJ H$ê$Z dJ© g‘rH$aU gmoS>{dʶmgmR>r Imbrb nm¶è¶m§Mm Adb§~ H$amdm.
nm¶ar 1 … g‘rH$aU ax2 + bx + c = 0 ¶m à‘m{UV Z‘wݶmV {bhm qH$dm à‘m{UV Z‘wݶmV AmUm (‘m§S>m).nm¶ar 2 … à‘m{UV Z‘wݶmer {Xboë¶m g‘rH$aUmMr VwbZm H$am Am{U a, b, c À¶m qH$‘Vr AmoiIm.
nm¶ar 3 … dJ© gyÌ2 4
2b b acx
a{bhm.
nm¶ar 4 … gyÌm‘ܶo a, b Am{U c À¶m qH$‘Vr ‘m§S>m (R>odm).nm¶ar 5 … gaiê$n Úm Am{U XmoZ ~rOo {‘idm.
ñdmܶm¶ 9.5
gyÌmMm Cn¶moJ H$ê$Z Imbrb dJ© g‘rH$aUo gmoS>dm.
1. x2 – 4x + 2 = 0 2. x2 – 2x + 4 = 0
3. 2y2 + 6y = 3 4. 15m2 – 11m + 2 = 0
5. 8r2 = r + 2 6. (2x + 3)(3x – 2) + 2 = 0
7. a(x2 + 1) = x(a2 + 1) 8. x2 + 8x + 6 = 0
{Xboë¶m dJ© g‘rH$aUmMr ~rOo doJdoJù¶m nÕVrZo H$mT>ʶmMo Amåhr {eH$bobmo AmhmoV. AmåhmbmAgo {XgyZ ¶oVo H$s ~rOo hr dmñVd g§»¶m AmhoV. øm ~rOm§Mo ñdê$n H$m¶ Amho? ~rOm§Mo ñdê$n H$emZo{ZYm©arV H$aVmV?
{Xboë¶m dJ© g‘rH$aUmÀ¶m ~rOm§Mo ñdê$n à˶j Z gmoS>{dVm {ZYm©arV H$aUo e³¶ Amho H$m¶? dJm©VMMm© H$am Am{U øm àým§Mr CÎmao XoʶmMm à¶ËZ H$am.
AmVm AmnU ˶m~Ôb {eHy$¶m.
dJ©g‘rH$aUm§À¶m ~rOm§Mo ñdê$n …
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210 UNIT-9
Imbrb CXmhaUm§Mm Aä¶mg H$am.
1. x2 – 2x + 1 = 0 ¶m g‘rH$aUmMm {dMma H$am.
ho ax2 + bx + c = 0 ¶m Z‘wݶmV Amho.
ghJwUH$ a = 1, b = –2, c = 1 AmhoV.
x =2 4
2b b ac
a x =
2( 2) (2) 4.1 12 1
x =2 4 4
2x =
2 02
x =2 0
2 qH$dm x =2 0
2 x = 1 qH$dm x = 1 ~rOo g‘mZ AmhoV.
2. x2 – 2x – 3 = 0 ¶m g‘rH$aUmMm {dMma H$am.
ho ax2 + bx + c = 0 ¶m Z‘wݶmV Amho.
ghJwUH$ a = 1, b = –2, c = –3 AmhoV.
x=2 4
2b b ac
ax =
2( 2) ( (-2) )4
.
112
21
+b = x =2 42
x =2 4
2
qH$dm x =2 4
2
x=62 qH$dm x =
22 x = 3 qH$dm x = -1 hr ñnï> ~rOo AmhoV.
3. x2 – 2x + 3 = 0 ¶m g‘rH$aUmMm {dMma H$am.
ho ax2 + bx + c = 0 ¶m Z‘wݶmV Amho.
ghJwUH$ a = 1, b = –2, c = 3 AmhoV.
x =2 4
2b b ac
ax =
2 2( 2) ( 2) 4(1)(3)2 1
x =2 4 12
2x =
2 82
x=2 2 2
2x = 2 1 2 1 2
2
1 2x qH$dm 1 2 ~rOo g§{H$U© AmhoV.
darb CXmhaUmdê$Z ho ÑT> hmoVo H$s dJ© g‘rH$aUmMr ~rOo dmñVd Am{U g‘mZ, dmñVd Am{U ñnï>g§{H$U© qH$dm H$mën{ZH$ AmhoV.
b2 – 4ac À¶m qH$‘Vr ~rOm§Mo ñdê$n {ZYm©arV H$aVmV ¶mMo gwÕm {ZarjU H$am. Amåhr Ago gm§Jy H$sb2 – 4ac À¶m qH$‘Vrda ~rOm§Mo ñdê$n Adb§~yZ AgVo.
ax2 + bx + c = 0 ¶mÀ¶m ~rOm§Mo ñdê$n b2 – 4ac À¶m amerÀ¶m qH$‘VrZo emoYVm ¶oVo Am{U åhUyZ ˶mbmdJ© g‘rH$aUmMo {ddoMH$ Ago åhUVmV. Vo ˶mbm dJ© g‘rH$aUmMo {ddoMH$ Ago åhUVmV. ¶m g§koZo
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Quadratic Equations 211
Xe©{dVmV Am{U S>oëQ>m Ago dmMVmV.
gm‘mݶnUo ax2 + bx + c = 0 ¶m dJ© g‘rH$aUmMr ~rOo x =2 4
2b b ac
a
• Oa b2 – 4ac = 0 Va g‘rH$aUmMr XmoZ ~rOo g‘mZ AgyZ dmñVd AgVmV. AemàH$mao x = 2ba
• Oa b2 – 4ac > 0 Va g‘rH$aUmMr XmoZ ~rOo ñnï> AgyZ dmñVd AgVmV.
AemàH$mao x =2 4
2b b ac
a, x =
2 42
b b aca
• Oa b2 – 4ac < 0 Va g‘rH$aUmMr ~rOo dmñVd ZmhrV.
Á¶mAWu 2( 4 )b ac ho AmT>iV Zmhr Am{U Amåhr Ago gm§Jy H$s Vo g§{H$U© Amho.
darb {ZîH$f© ho Imbr {Xboë¶m gmaUrV Xe©{dbobo AmhoV.{ddoMH$ ~rOm§Mo ñdê$n
= 0 dmñVd Am{U g‘mZ > 0 dmñVd Am{U ñnï> < 0 dmñVd ~rOo ZmhrV (g§{H$U© ~rOo)
gmoS>{dbobr CXmhaUo
CXmhaU 1) 2x2 – 5x – 1 = 0 ¶m g‘rH$aUmÀ¶m ~rOm§Mo ñdê$n AmoiIm.
CH$b … ho ax2 + bx + c = 0 ¶m Z‘wݶmV Amho. ghJwUH$ a = 2, b = –5, c = –1 AmhoV. = b2 – 4ac = (–5)2 –4(2) (–1) = 25 + 8 = 33
> 0 åhUyZ ~rOo dmñVd Am{U ñnï> AmhoV.
CXmhaU 2) 4x2 – 4x + 1 = 0 ¶m g‘rH$aUmÀ¶m ~rOm§Mo ñdê$n AmoiIm.
CH$b … 4x2 – 4x + 1 = 0 ¶m g‘rH$aUmMm {dMma H$am.
ho ax2 + bx + c = 0 ¶m Z‘wݶmV Amho. a = 4, b = –4, c = 1 ho ghJwUH$ AmhoV. = b2 – 4ac = (–4)2 – 4(4) (1) = 16 – 16
= 0 ~rOo dmñVd Am{U g‘mZ AmhoV.
CXmhaU 3) 'm' À¶m H$moU˶m qH$‘Vrg x2 + mx + 4 = 0 Mr ~rOo (i) g‘mZ (ii) ñnï> AmhoV.
CH$b … x2 + mx + 4 = 0 ¶m g‘rH$aUmMm {dMma H$am.
ho ax2 + bx + c = 0 ¶m Z‘wݶmV Amho. a = 1, b = m, c = 4 ho ghJwUH$ AmhoV. = b2 – 4ac = m2 – 4(1)(4) = m2 – 16
(i) Oa ~rOo g‘mZ AgVrb Va = 0 m2– 16 = 0 m2 = 16 m = 16 m = 4
(ii) Oa ~rOo ñnï> AgVrb Va 0 m2– 16 0 m2 16 m 16 m 4
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212 UNIT-9
ñdmܶm¶ 9.6
A. Imbrb g‘rH$aUm§À¶m ~rOm§À¶m ñdê$nm§Mr MMm© H$am. (~rOm§Mo ñdê$n AmoiIm)i) y2 - 7y + 2 = 0 ii) x2 - 2x + 3 = 0 iii) 2n2 + 5n - 1 = 0iv) a2 + 4a + 4 = 0 v) x2 + 3x - 4 = 0 vi) 3d2 - 2d + 1 = 0
B. ‘m’ À¶m H$moU˶m KZ qH$‘Vrg Imbrb g‘rH$aUmMr ~rOo
1) g‘mZ 2) ñnï 3) g§{H$U© AgVmVi) a2-ma+1=0 ii) x2-mx+9=0 iii) r2-(m+1) r+4=0 iv) mk2-3k+1=0
C. dJ© g‘rH$aUm§Mr ~rOo g‘mZ AgVrb Va ‘P’ Mr qH$‘V H$mT>m.i) x2-px+9 = 0 ii) 2a2+3a+p = 0 iii) pk2-12k+9 = 0 iv) 2y2-py+1 = 0v) (p+1) n2+2 (p+3)n+(p+8)=0 vi) (3p+1)c2+2(p+1)c+p=0
dJ© g‘rH$aUmÀ¶m nXm§Mo ghJwUH$ Am{U ~rOo ¶m‘Yrb g§~§Y …
Oa ax2+bx+c=0 ¶m dJ© g‘rH$aUmMr ~rOo ‘m’ Am{U ‘n’ AgVrb Va
m =2 4
2b b ac
aAm{U n =
2 42
b b aca
m+n =2 4
2b b ac
a +
2 42
b b aca
=2 24 4
2b b ac b b ac
a =
22
ba
m + n =b
a
mn =2 4
2b b ac
a
2 42
b b aca =
22 2
2
4
4
b b ac
a
mn =2 2
2
44
b b aca
=2 2
2 2
4 44 4
b b ac aca a
mn =ca
Oa ax2 + bx + c = 0 ¶m dJ© g‘rH$aUmMr ~rOo m d n AgVrb Va
~rOm§Mr ~oarO = m+ n=b
a ~rOm§Mm JwUmH$ma =m n=c
a
ñnîQ>rH$aUmË‘H$ CXmhaUo
CXmhaU 1) x2 + 2x + 1 = 0 ¶m g‘rH$aUmÀ¶m ~rOm§Mr ~oarO Am{U JwUmH$ma H$mT>m.
CH$b … ho ax2 + bx + c = 0 ¶m ñdê$nmV Amho. a =1, b = 2, c=1 ho ghJwUH$ AmhoV.
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Quadratic Equations 213
~rOo m Am{U n ‘mZy.
i) ~rOm§Mr ~oarO m+n =b
a =2
1 2m n
ii) ~rOm§Mm JwUmH$ma mn =ca
=11 1mn
CXmhaU 2) 3x2 + 5 = 0 ¶m g‘rH$aUmÀ¶m ~rOm§Mr ~oarO Am{U JwUmH$ma H$mT>m.
CH$b … ho ax2 + bx + c = 0 ¶m Z‘wݶmV Amho. a = 3, b = 0, c = 5
~rOo p Am{U q AmhoV Ago ‘mZy.
i) ~rOm§Mr ~oarO p+q =b
a =
03
p q 0+
ii) ~rOm§Mm JwUmH$ma pq =ca
=53
5pq3
ñdmܶm¶ 9.7
g‘rH$aUmÀ¶m ~rOm§Mr ~oarO Am{U JwUmH$ma H$mT>m.
1. x2 – 5x + 8 = 0 2. 3a2 – 10a – 5 = 0 3. 8m2 – m = 2
4. 6k2 – 3 = 0 5. pr2 = r – 5 6. x2 + (ab) x + (a + b) = 0
dJ© g‘rH$aU aMUo …
{Xboë¶m dJ© g‘rH$aUmMr ~rOo Am{U ˶m§Mr ~oarO Am{U JwUmH$ma gwÕm H$mT>Uo ¶m~Ôb Amåhmbm ‘m{hVAmho.
~rOm§Mr ~oarO Am{U JwUmH$ma {Xbo AgVm dJ© g‘rH$aU aMUo e³¶ Amho H$m¶?
Oa 'm' Am{U 'n' hr ~rOo AgVrb Va g‘rH$aUmMm gm‘mݶ Z‘wZm x2 – (~rOm§Mr ~oarO) x+ (~rOm§§Mm JwUmH$ma) = 0 Amho. x2 – (m + n) x + mn = 0.
ñnîQ>rH$aUmË‘H$ CXmhaUo
CXmhaU 1) 2 Am{U 3 ~rOo AgUmao dJ© g‘rH$aU aMm.CH$b … 'm' Am{U 'n' hr ~rOo ‘mZm m = 2, n = 3
~rOm§Mr ~oarO = m + n = 2 + 3 m + n = 5~rOm§Mm JwUmH$ma = mn = (2) (3) mn = 6BpÀN>V g‘rH$aU = x2 – (m + n)x + mn = 0 x2 – (5)x + (6) = 0
2 5 6 0x xCXmhaU 2) 3 2 5 Am{U 3 2 5 ~rOo AgUmao dJ© g‘rH$aU aMm.
CH$b … 'm' Am{U 'n' ‘mZy m = 3 2 5 and n = 3 2 5
~rOm§Mr ~oarO = m + n = 3 2 5 3 2 5 6m n
~rOm§Mm JwUmH$ma = mn = 3 2 5 3 2 5 = (3)2 –2
2 5 = 9-n(5)= 9 – 20 11mn
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214 UNIT-9
x2 – (m + n) x + mn = 0 x2 – 6x – 11 = 0CXmhaU 3) Oa x2 – 3x + 1 = 0 ¶m g‘rH$aUmMr ~rOo 'm' Am{U 'n' AgVrb Va
(i)m2n + mn2 (ii) 1 1m n
Mr qH$‘V H$mT>m
CH$b … x2 – 3x + 1 = 0 ¶m g‘rH$aUmMm {dMma H$am.
ho ax2 + bx + c = 0 ¶m Z‘wݶmV Amho. a = 1, b = –3, c = 1 ho ghJwUH$ AmhoV.
(i) ~rOm§Mr ~oarO m + n =( 3) 31
ba 3m n
(ii) ~rOm§Mm JwUmH$ma mn =ca =
11 1mn
åhUyZ
(i) m2n + mn2 = mn (m + n) = 1 × 3 = 3
(ii)1 1m n
=31
n m m nmn mn
= 31 1 3m n
CXmhaU 4) 'm' Am{U 'n' hr x2 – 3x + 4 = 0 ¶m g‘rH$aUm§Mr ~rOo AgVrb Va m2 d n2 ~rOo AgUmao
dJ© g‘rH$aU aMm.
CH$b … x2 – 3x + 4 =0 ¶m g‘rH$aUmMm {dMma H$am. a = 1, b = –3, c = 4 ho ghJwUH$ Amho.
(i) ~rOm§Mr ~oarO = m + n =( 3)1
ba 3m n
(ii) ~rOm§Mm JwUmH$ma= mn =ca =
41 mn = 4
Oa m2 Am{U n2 hr ~rOo AgVrb Va
~rOm§Mr ~oarO m2 + n2 = (m + n)2 – 2mn = (3)2 – 2(4) = 9 – 8 m2 + n2 = 1
~rOm§Mm JwUmH$ma m2n2 = (mn)2 = 42 m2n2 = 16
x2 – (m2 + n2)x + m2n2 = 0 x2 – (1)x + (16) = 0 2 16 0x x
CXmhaU 5) x2 – 6x + q = 0 ¶m g‘rH$aUmMo EH$ ~rO Xþgè¶m ~rOmÀ¶m XþßnQ> Amho Va 'q' Mr qH$‘V H$mT>m.
CH$b … x2 – 6x + q = 0 ¶m g‘rH$aUmMm {dMma H$am. OoWo a = 1, b = –6, c = q
(i) ~rOm§Mr ~oarO m + n =( 6)1
ba 6m n
(ii) ~rOm§Mm JwUmH$ma mn = 1c qa mn = q
Oa EH$ ~rO m Agob Va XþßnQ> ~rO 2m Amho. m = m Am{U n = 2m
m + n = 6 m + 2m = 6 3m = 6 m =63
= 2
Amåhmbm ‘mhrV Amho H$s q = mn q = m(2m) 2m2 = 2(2)2 = 8 q = 8
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Quadratic Equations 215
CXmhaU 6) x2 – 2x + (k + 3) = 0 ¶m g‘rH$aUmMo EH$ ~rO eyݶ Amho Va k Mr qH$‘V H$mT>m.
CH$b … x2 – 2x + (k + 3) = 0 ¶m g‘rH$aUmMm {dMma H$am. a = 1, b = –2, c = k + 3 ho ghJwUH$ AmhoV.
~rOm§Mm JwUmH$ma = mn
mn =ca mn =
31
kmn = k + 3
åhUyZ 'm' Am{U 'n' hr ~rOo AmhoV Am{U EH$ ~rO eyݶ Amho Va
m = m Am{U n = 0, mn = k + 3
m(0) = k + 3 0 = k + 3 k = –3.
ñdmܶm¶ 9.8
A. Imbrbà‘mUo ~rOo AgUmao dJ© g‘rH$aU aMm.
i) 3 Am{U 5 ii) 6 Am{U –5 iii) –3 Am{U32 iv)
23 Am{U
32
v) 2 3 Am{U 2 3 vi) 3 2 5 Am{U 3 2 5
B.1. Oa 'm' Am{U 'n' hr x2 – 6x + 2 = 0 ¶m g‘rH$aUmMr ~rOo AgVrb Va qH$‘Vr H$mT>m.
(i) (m + n) mn (ii)1 1m n (iii) 3 2 3 2m n n m (iv)
1 1n m
2. Oa 'a' Am{U 'b' hr 3m2 = 6m + 5 ¶m g‘rH$aUmMr ~rOo AmhoV Va qH$‘Vr H$mT>m.
(i)a bb a (ii) (a + 2b)(2a + b)
3. Oa 'p' Am{U 'q' hr 2a2 – 4a + 1 = 0 ¶m g‘rH$aUmMr ~rOo AmhoV Va qH$‘Vr H$mT>m.
(i) (p + q)2 + 4pq (ii) p3 + q3
4.pq Am{U
qp ~rOo AgUmao dJ© g‘rH$aU aMm.
5. x2 + 4x + (k + 2) = 0 ¶m g‘rH$aUmMo EH$ ~rO eyݶ Amho Va 'k' Mr qH$‘V H$mT>m.
6. 2x2 – 3qx + 5q = 0 ¶m g‘rH$aUmMo EH$ ~rO Xþgè¶m ~rOmÀ¶m XþßnQ> Amho Va 'q' Mr qH$‘V H$mT>m.
7. 4x2 – 8px + 9 = 0 ¶m g‘rH$aUmÀ¶m ~rOm‘Yrb ’$aH$ 4 Amho Va 'p' Mr qH$‘V H$mT>m.
8. Oa x2 + px + q = 0 ¶m g‘rH$aUmMo EH$ ~rO Xþgè¶m ~rOmÀ¶m {VßnQ> Agob Va 3p2 = 16q Ago {gÕ H$am.
D. AmboI nÕVrZo dJ© g‘rH$aUmMr CH$b …
aofr¶ g‘rH$aUmMo AmboI H$mT>Uo Am{U g‘¶m{‘H$ aofr¶ g‘rH$aUo gwÕm AmboImZo gmoS>{dUo ¶m~Ôb
Vwåhr n[a{MV AmhmV.
CXmhaU 1) 0 = x2 ¶m dJ© g‘rH$aUmMm {dMma H$am. Amåhmbm q~XÿÀ¶m gh{ZX}eH$mMm AmboI H$mT>ʶmMr Oê$ar Amho.
AmnU y = x2 ¶m g‘rH$aUmÀ¶m 'x' Am{U 'y' qH$‘VrMm Vº$m y=x ¶m g‘rH$aUmgmR>r V¶ma H$é.
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216 UNIT-9
2 1 0 1 24 1 0 1 4
xy
A(–2, 4), B(–1, 1), C(0, 0), D(1, 1)
Am{U E(2, 4) ho q~Xÿ ñWm{nV H$am.
q~Xÿ dH«$ H§$gmZo gm§Ym.
y = x2 Mm AmboI dH«$ aofm Amho.
XmoZ A{YH$ dJ© g‘rH$aUm§À¶m AmboIm§Mo {ZarjU H$am.
CXmhaU 2) 2x2 =0 CXmhaU 3) 21 02
x
2 1 0 1 28 2 0 2 8
xy
2 1 0 1 22 ½ 0 ½ 2
xy
AemàH$mao Amåhmbm Ago {XgyZ ¶oVo H$s dJ© g‘rH$aUo 0 = x2, 0 = 2x2 Am{U 0 = 212
x AmboI dH«$aofm
AmhoV. dJ© g‘rH$aUo Xe©{dUmè¶m ¶m dH«$ aofobm "nadb¶' Ago åhUVmV.
dJ© g‘rH$aUm§À¶m øm AmboImdê$Z Amåhmbm Ago AmT>iVo H$s ({XgyZ ¶oVo H$s).
• AmboImMo nadb¶ ho g§~§{YV Ajmer à‘mU~Õ AmhoV.
• dH«$Vm OoWo gdm©V ‘moR>r AgVo ˶m q~Xÿbm {eamoq~Xÿ Ago åhUVmV. nadb¶ ¶m q~Xÿda diU KoVmo.
AmmVm AmnU nadb¶ ¶m~Ôb A{YH$ {eHy$.(x2 – 4x) Am{U (–x2 + 2x + 5) ¶m amer {dMmamV ¿¶m.
1. x2 – 4x 2. –x2 + 2x + 5¶oWo 'a' ho eyݶmnojm ‘moR>o Amho. ¶oWo a hr eyݶmnojm H$‘r Amho.y = x2 – 4x ‘mZm. y = – x2 + 2x + 5 ‘mZm.
• qH$‘VrMm Vº$m V¶ma H$am. •AmnU qH$‘VrMm Vº$m V¶ma H$ê$.
X O X
Y
654321
1 2 3–1–2–3
Y
E(2, 4)A(–2, 4)
B(—1, 1) D(1, 1)C(0, 0)
x - axis : 1cm = 1unit y - axis : 1 cm =1unit
X¢–2–3–4–5
98
76543
21
X O 12345–1
Y
Y¢
E(2,8)A(-2,8)
B(–1,2) D(1,2)
C(0,0)
x - axis : 1cm = 1unit y - axis : 1 cm =0.5unit
X I
–2–3
2.5
2
1.5
1
0.5
X O 1 2 3–1
Y
YI
P(-2,2)
R(0,0)
T(2,2)
S(1, 0.5)Q(-1,0.5)
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Quadratic Equations 217
–x2 + 2x + 5• nadb¶ Imbrb {Xeobm {demb hmoV OmVmo.• H$‘rV H$‘r q~Xÿ JmR>on¶ªV x Mr qH$‘V OgOer
dmT>V OmVo Ver y Mr gwÕm qH$‘V dmT>V OmVo.• y Mr ‘moR>çmV ‘moR>r qH$‘V 6 Amho.
x2 – 4x• nadb¶ darb {Xeobm {demb hmoV OmVmo.• y Mr {H$‘mZ qH$‘V JmR>on¶ªV OgOer x Mr
qH$‘V dmT>V OmVo VgVer y Mr qH$‘V H$‘rhmoV OmVo.
• y Mr gdm©V H$‘r qH$‘V –4 Amho.
Y
X O X¢
Y¢
54321
–1–2
–3–4–5
1 2 3 4 5–1–2–3–4–5
D(3,–3)B(1, 3)
A(–1, 5)F(5, 5)
E(4,0)
C(2 –4)
x - axis : 1cm = 1unit y - axis : 1 cm =1unit
Y
X OX
Y
654321
–1–2–3–4–5
1 2 3 4 5–1–2–3–4–5
D(1,6)
C(0, 5) E(2, 5)
F(3,2)B(–1,2)
A(–2,–3)
x - axis : 1cm = 1unit y - axis : 1 cm =1unit
1 0 1 2 3 4 55 0 3 4 3 0 5
xy
-- - -
2 1 0 1 2 33 2 5 6 5 2
xy
• à˶oH$ H«${‘V OmoS>r (x, y) Mo q~Xÿ ñWmnZ H$am. • à˶oH$ H«${‘V OmoS>r (x, y) Mo q~Xÿ ñWmnZ H$am.
• ñWmnZ Ho$boë¶m q~XÿVyZ dH«$ H§$g H$mT>m. • ñWmnZ Ho$boë¶m q~XÿVyZ dH«$ H§$g H$mT>m.
darb XmoÝhr AmboImdê$Z Amåhr Imbrb {ZarjUo ‘m§Sy>.
ñdmܶm¶ 9.9
I. Imbrb dJ© g‘rH$aUm§Mo AmboI H$mT>m.
i) y = –x2 ii) y = 3x2 iii) y x = - 2212 iv) y = x2 – 2x
v) y = x2 – 8x + 7 vi) y = (x + 2)(2 – x) vii) y = x2 + x – 6 viii) y = x2 – 2x + 5
dJ© g‘rH$aUm§À¶m AmboIr¶ CH$br …
¶m ^mJmV AmnU dJ©g‘rH$aUo gmoS>{dʶmÀ¶m AmboIr¶ nÕVrMm Aä¶mg H$ê$.
gmoS>{dbobr CXmhaUo
CXmhaU 1) y = x2 – x – 2 ho g‘rH$aUMm AmboI H$mT>m Am{U ~rOo H$mT>m.
CH$b … AmnU ¶m g‘rH$aUMm AmboI H$mTy> Am{U ~rOo AmboImZo H$mTy>
nm¶ar 1 … y = x2 – x – 2 À¶m qH$‘VrMm Vº$m V¶ma H$am.
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218 UNIT-9
2 1 0 1 24 0 2 2 0
xy
nadb¶ AmboI H$mT>m. x –Ajmbm nadb¶ AmboI N>oXUmao gh{ZXo}eH${bhm
g{‘H$aUmMr ~rOo x = – 1Am{U x =2 hr AmhoV.
nmÜXV 2 … x2 – x –2= x2 = x + 2
y = x2 ‘mZy ..............(1) Am{U y = x +2-2........(2)
2 1 00
11
24 40
xy
2101
22 4 0
xy
g‘r 1 Am{U 2 Mm nadb¶ Am{U aofm AmboI H$mT>m.gai aofm
nadb¶ AmboImbm N>oXUmè¶m q~XÿMo gh {ZXo}eH$ {bhm Vo B (-1,0) Am{U
E (2,0) ho AmhV.
g‘r. Mr ~rOo x =-1 Am{U x = 2 hr AmhoV.
CXmhaU 2) x2 -10x +25 ho dJ© g‘rH$aU AmboImZo gmoS>mdm.
CH$b: y = x2 -10x +25 ¶m g‘rH$aUmÀ¶m qH$‘VrMm VÎH$m V¶maH$am.
1 2 3 4 5 616 9 4 1 0 1
xy
gd© q~Xÿ AmboImda ñWmnZ H$am Am{U ñWm{nV q~XÿVyZ dH«$aofm H$mT>m.x- AjmÀ¶m Am{U dH«$ aofoÀ¶m N>oXZ q~XÿÀ¶m IwUm H$am.
dH«$ aofm x- Ajmbm ’$º$ (5,0) ¶m EH$ q~XÿV N>oXVo.g‘rH$aUmMr ~rOo 5 Am{U 5 hr AmhoV.
CXmhaU 3 … y = x2 + 2 Mm AmboI aMm Am{U ~rOo H$mT>m.
CH$b … nm¶ar 1 … y = x2 + 2 ¶m g‘rH$aUmÀ¶m qH$‘VrMm Vº$m V¶maH$am.
2 1 0 1 26 3 2 3 6
xy
Y
X O X¢
Y¢
54321
–1–2–3–4–5
1 2 3 4 5–1–2–3–4–5
D(1,–2)
B(–1, 0)
A(–2, 4)
E(2,0)
C(0 –2) - interceptx - interceptx
x - axis : 1cm = 1unit y - axis : 1 cm =1unit
Y
X O X¢
Y¢
252015105
1 2 3 4 5 6–1–2–3–4
A(1,16)
= –10 +25y x x2
x - intercept
B(2,9)
C(3,4) D(4
,1)
E(5,
0)F(
6,0)
Y
X O X¢
Y¢
87654
321
1 2 3 4 5–1–2–3–4–5
A(–2, 6)
B(–1, 3) D(1, 3)
E(2, 6)
C(0, 2)
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Quadratic Equations 219
dH«$ aofm x- Ajmbm N>oXZ Zmhr.VoWo x2 + 2x = 0 gmR>r x Mr dmñVd qH$‘V Zmhr.
åhUyZ VoWo dmñVd ~rOo ZmhrV.
darb {VÝhr CXmhaUmMm Vnerb AmVm AmnU V³Ë¶mV Zm|X H$ê$. ˶mMm Aä¶mg H$am.
x2 – x – 2 x2 – 10x + 25 x2 + 2˶mbm XmoZ N>oXZ ˶mbm EH$ N>oXZ ˶mbm N>oXZ
q~oXÿ AmhoV. q~oXÿ Amho. q~oXÿ ZmhrV.
X X
2 solutions
X X
1 solutions
X X
No solutionsax2 + bx + c = 0 bm ax2 + bx + c = 0 bm ax2 + bx + c = 0 bmXmoZ dmñVd Am{U XmoZ dmñVd Am{U dmñVd ~rOo ZmhrV
Ag‘mZ ~rOo AmhoV nwZamd{V©V ~rOo AmhoVb2 – 4ac > 0 b2 – 4ac = 0 b2 – 4ac < 0
CXmhaU 4) y = (2 – x)(4 + x) ho gd© g‘rH$aU AmboImZo gmoS>dm.
CH$b … y = (2 – x)(4 + x) Amho.
COì¶m ~mOybm gaiê$n Úm Am{U ax2 + bx + c = 0 à‘m{UV Z‘wݶmV AmUm.
y = (2 – x)(4 + x)
y = –x2 – 2x + 8
4 3 2 1 0 1 20 5 8 9 8 5 0
xy
x - Ajmbm nadb¶ AmboI NoXZmè¶m> q~XÿZm IwUm H$am. NoXZmao q~Xy (-4,0 ) Am{U (2,0) AmhoV.
åhUyZ 2 Am{U -4 hr ~rOo AmhoV.
CXmhaU 5 … y = 2x2 Mm AmboI H$mT>m Am{U AmboImMm Cn¶moJH$ê$Z 5 Mr qH$‘V H$mT>m.
CH$b … nm¶ar 1 … y = 2x2 ¶m g‘rH$aUmMrnyV©Vm H$aUmè¶m x Am{U y À¶m g§JVqH$‘VrMm Vº$m aMm.
0 1 1 2 2 50 2 2 8 8 10
xy
Y
X O X¢
Y¢
987654321
1 2 3 4 5–1–2–3–4–5
C(–2, 8) E(0, 8)
F(1, 5)B(–3, 5)
D(–1, 9)
A(–4, 0) G(2, 0)
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220 UNIT-9
nm¶ar 2 … gd© q~Xy AmboI nÌmda ñWm{nV H$am Am{Unadb¶ H$mT>m.
nm¶ar 3 … Ooìhm 5 5x 102
y= = =2x-Ajmbm g‘m§Va AgUmar y = 10 hr gaiaofm H$mT>m.nm¶ar 4 … nadb¶ Am{U gaiaofm N> oXZ q~X ÿV yZx-Ajmda b§~ H$mT>m.nm¶ar 5 … x- Ajmdarb q~Xÿ‘ܶo {‘iUmao b§~ hoM
5 Mr qH$‘V Amho.
x = 2.3
5 2 3 = .
ñdmܶm¶ 9.10I. Imbrb dJ© g‘rH$aUmMo AmboI H$mT>m.
i) x2–4x=0 ii)x2 +x – 12 =0 iii) x2 – x – 2 =0 iv) x2 – 5x + 6 = 0
II.1. y = x2 Mm AmboI H$mT>m Am{U 3 Mr qH$‘V H$mT>m.
2. y = x2 Mm AmboI H$mT>m Am{U 7 Mr qH$‘V H$mT>m.
3. y =12 x2 Mm AmboI H$mT>m Am{U 10 Mr qH$‘V H$mT>m.
dJ© g‘rH$aUmda AmYmarV CXmhaUo gmoS>{dUo (Solving problems based on quadratic equations)
Amnë¶m X¡Z§{XZ OrdZmV Ago nwîH$i àg§J ¶oVmV H$s OoWo Amåhr dJ© g‘rH$aUo gmoS>{dʶmÀ¶m nÕVrMmdmna H$ê$Z Amåhr Vr CXmhaUo gmoS>{dVmo. AmnU H$mhr CXmhaUm§Mm {dMma H$ê$
gmoS>{dbobr CXmhaUo
CXmhaU 1 … XmoZ H«$‘dma YZ {df‘ g§»¶mMm JwUmH$ma 195 Amho. Va ˶m g§»¶m H$mT>m.
CH$b … nm¶ar 1 … g‘rH$aU aMUo
EH$ {df‘ YZ g§»¶m x ‘mZm Am{U Xþgar {df‘ YZ g§»¶m (x + 2) hmoB©b.
g§»¶m§Mm JwUmH$ma x(x + 2) = 195 Amho.
nm¶ar 2 … g‘rH$aU gmoS>{dUo
Y
X OX
1110987654321
1 2 3 4 5–1–2–3–4–5
=10y
D(–2, 8) C(2, 8)
A(1, 2)B(–1, 2)
= –2.3x = 2.3x
Y
5 = ± 2.3
AMyH$ CH$b A§XmOo CH$b
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Quadratic Equations 221
x(x + 2) = 195
x2 + 2x = 195
x2 + 2x – 195 = 0
x2 + 15x – 13x – 195 = 0
x + 15 = 0 or x – 13 = 0
(x + 15)(x – 13) = 0
x + 15 = 0 qH$dm x – 13 = 0
x = – 15 qH$dm x = 13
nm¶ar 3 … ñnï>rH$aU H$aUo Am{U CH$b H$mT>Uo Ho$ìhmhr g§»¶m YZ Agmdr. x = – 15 ho KoVm ¶oV Zmhr.
x = 13 Am{U x + 2 = 13 + 2 = 15
XmoZ H«$‘dma {df‘ YZ g§»¶m 13 Am{U 15 AmhoV.
CXmhaU 2 … AÛ¡VZo 60 é. Zm H$mhr nwñVHo$ {dH$V AmUbr (KoVbr) Oa ˶mZo {VV³¶mM a¸$‘oV 5 nwñVHo$A{YH$ KoVbr AgVr Va à˶oH$ nwñVH$mMr qH$‘V 1 Zo H$‘r Pmbr AgVr. Va AÛ¡VZo IaoXr Ho$boë¶mnwñVH$m§Mr g§»¶m {H$Vr Am{U à˶oH$ nwñVH$mMr qH$‘V {H$Vr.CH$b … nm¶ar 1 … nwñVH$m§Mr g§»¶m = x ‘mZy.
nwñVH$m§Mr EHy$U qH$‘V = 60 é. à˶oH$ nwñVH$mMr qH$‘V =60x
é.
Oa nwñVH$mMr g§»¶m (x + 5) Agob Va à˶oH$ nwñVH$mMr qH$‘V =60
5xé. hmoB©b
IaoXr qH$‘VrVrb =
’$aH$ 1 é. Amho.
CH$b:60 60
5x x= 1
60( 5) 60( 5)
x xx x = 1
2
60 300 605
x xx x
= 1 2
3005x x
=11
x2 + 5x = 300 x2 + 5x – 300 = 0
x2 + 20x – 15x – 300 = 0 x(x + 20) – 15 (x + 20) = 0
(x + 20)(x – 15) = 0
EH§$Xa x + 20 = 0 qH$dm x – 15 = 0
x = – 20 qH$dm x = 15
nwñVH$m§Mr g§»¶m = x = 15
nwñVH$m§Mr qH$‘V Ho$ìhmhr F$U ZgVo åhUyZ -15 ho dJibo Amho.à˶oH$ nwñVH$mMr qH$‘V =
60 6015x
= ` 4 ê$.
nwñVH$mMr g§»¶m AgVmZmà˶oH$ nwñVH$mMr qH$‘V
x nwñVH$mMr g§»¶m AgVmZmà˶oH$ nwñVH$mMr qH$‘V
(x+5)
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222 UNIT-9
ñdmܶm¶ 9.11
1. XmoZ H«$‘dma {df‘ YZ g§»¶m Aem H$mT>m H$s ˶m§À¶m dJmªMr ~oarO 130 hmoB©b.2. EH$m g§»¶oÀ¶m dJm©À¶m {VßnQ>rhÿZ ˶mM g§»¶oMr Mma nQ> dOm Ho$ë¶mg g§»¶m 15 ¶oVo Va Vr nyU© g§»¶m
H$mT>m.3. XmoZ Z¡g{J©H$ g§»¶mMr ~oarO 8 Amho. Oa ˶m§À¶m ì¶ñVm§Mr ~oarO
8.
15Amho Va ˶m g§»¶m AmoiIm.
4. EH$ XmoZ A§H$s g§»¶m Aer Amho H$s ˶m§À¶m A§H$mMm JwUmH$ma 12 Amho. Ooìhm ˶m g§»¶oV 36{‘i{dë¶mg A§H$mÀ¶m ñWmZm§Mr AXbm~Xb hmoVo Va ˶m g§»¶m AmoiIm.
5. VrZ H«$‘dma YZ nyUmªH$mMr ~oarO Aer Amho H$s n{hë¶m g§»¶oMm dJ© Am{U BVa XmoZ g§»¶mMm JwUmH$ma¶m§Mr ~oarO 154 Amho Va nyUmªH$ H$mT>m.
6. gwOb Am{U 춧H$Q> ¶m§Mr d¶o 11 df} Am{U 14 df} AmhoV. {H$Vr dfm©V ˶m§À¶m d¶m§Mm JwUmH$ma 304hmoB©b.
7. d¶ {VÀ¶m ‘wbmÀ¶m d¶mÀ¶m dJm©À¶m XþßnQ>r BVHo$ Amho. 8 dfm©Z§Va ˶m AmB©Mo d¶ ˶mÀ¶m ‘wbmÀ¶md¶mÀ¶m {VßnQ>rnojm 4 dfm©Zo A{YH$ Amho. Va ˶m§Mr AmVmMr d¶o H$mT>m.
8. Am¶VmMo joÌ’$i 56 Mm¡.g|.‘r. Amho. Oa ˶mÀ¶m nm¶mMo ‘mn (x + 5) Am{U ˶mMr C§Mr (x – 5) Amho.Va Am¶VmMr ‘mno H$mT>m.
9. {ÌH$moUmMr b§~ C§Mr ˶mÀ¶m nm¶mnojm 6 g|.‘r.Zo A{YH$ Amho. ˶mMo joÌ’$i 108 Mm¡.g|.‘r. Amho. Va˶mMm nm¶m H$mT>m.
10. ABCD g‘^wO Mm¡H$moZmMo AC BCAm{U H$U© E ‘ܶo N>oXVmV. Oa AE = x, BE = x + 7 Am{U
AB = x + 8 Va AC Am{U BD H$UmªMr bm§~r H$mT>m.
11. ABC g‘Ûr wO {ÌH$moUmV AB BC Am{U BD hm AC nm¶mda H$mT>bobm b§~ Amho. Oa DC = x,BD = 2x – 1 Am{U BC = 2x + 1 Va {ÌH$moUmÀ¶m {VÝhr ~mOy§Mr bm§~r H$mT>m.
12. EH$m ¶m§{ÌH$ ~moQ>tMm g§W nmʶmVrb doJ 15 {H$.‘r./Vmg AgyZ àdmhmÀ¶m {XeoZo Am{U naV ‘mJo 30{H$.‘r. A§Va 4 Vmg 30 {‘{ZQ>mV OmVo. Va àdmhmMm doJ AmoiIm.
13. EH$m ì¶mnmè¶mZo EH$ dñVy é.24 bm {dH$ë¶mZo ˶mÀ¶m IaoXr qH$‘Vr EdT>m eoH$S>m Z’$m hmoVmo. Va ˶mdñVwMr IaoXr qH$‘V H$mT>m.
14. AmpídZrbm EH$ H$m‘ nyU© H$aʶmg YZlr nojm 6 {Xdg H$‘r bmJVmV. Va VoM H$m‘ XmoKr AmpídZr
Am{U YZlr {‘iyZ 4 {XdgmV VoM H$m‘ nyU© H$aV AgVrb Va YZlr EH$Q>rbm Vo H$m‘ nyU© H$aʶmg{H$Vr {Xdg bmJVrb?
* * *
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Quadratic Equations 223
CÎmao
ñdmܶm¶ 9.2
2. (i) 14 (ii) 5 5 (iii) 10 (iv)8
7(v) –2 {H$dm –14 (vi) 4 (vii) 9 (viii)
1
4. (i) r = 27
(ii) d = 3 (iii) b = 15 (iv) a = 8 (v) v = 10 (vi) v = 20
ñdmܶm¶ 9.3
1. –10, –5 2. –3, 2 3.1
10,
1
104. - 2,
2
5
dJ© g‘rH$aUo
dJ© Ed dJ© g‘rH$aUax2 + c = 0
A dJ© Ed dJ©g‘rH$aU
ax2 + bx + c = 0
~rOo Am{U ghJwUH$¶m‘Yrb g§~§Y
~rOm§Mo ñdê$n
dJ© g‘rH$aUo gmoS>{dUo~rOm§Mr ~oarO
m + n =-ba
{ddoMH$= b2 – 4ac
~rOo dmñVdd g‘mZ
~rOo dmñVdd ñnï>
~rOo g§H$sU©
~rOm§Mm JwUmH$ma
mn =ca
dJ© g‘rH$aUo aMUo2x (m n)x mn 0
Ad¶d nÕV
nyU© dJ© nÕV
gyÌ nÕV
AmboI nÕV
= 0
> 0
< 0
2 , 3 .... nadb¶MmCn¶moJ H$ê$Z emoYUo
nadb¶ nÕVrZodJ©g‘rH$aUo gmoS>{dUo
nadb¶ aMUo
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224 UNIT-9
5. –2k, 6. 7, –1 7.10 2
-3 1, 8.
3– 5
5,
9.5 3
– ,2 2 10.52 , 5 11.
1 1,b2 2a
12. 6, –1
ñdmܶm¶ 9.4
1. (i)9 1
,2 2
(ii) 1,-5
4(iii) –3,
1
2(iv) –8 ± 73 (v) 3± 5
2(vi) -3± 37
2
ñdmܶm¶ 9.5
1. 2 2 2. 1 -3 3.15–3
24.
2 1
5 3, 5.
651
16
6.1 -4
2 3, 7. a,
1
a8. - 4 10
ñdmܶm¶ 9.6
C. (i) 6 (ii)9
8(iii) 4 (iv) 22 (v)
1
3(vi) 1,
1
2ñdmܶm¶ 9.7
1. 5, 8 2.10 -5
3 3, 3.
1 -1
8 4, 4. 0,
-1
25.
1 5
p p, 6. –ab, (a+b)
ñdmܶm¶ 9.8
B 1. (i) 12 (ii) 3 (iii) 24 (iv) 7
2. (i)-22
5(ii)
19
33. (i) 6 (ii) 5 5. –2 6. 5 7.
5
2
ñdmܶm¶ 9.11
1. 7, 9 2. 3 3. 3, 5 {H$dm 5, 3 4. 26 5. 8, 9, 10 6. 5 7. 32, d 4 df}
8. 14 go.‘r , 4go.‘r 9. 12go.‘r, 18go.‘r 10. 10go.‘r, 24 go.‘r 11. 5go.‘r, 8 go.‘r
17 go.‘r, 17 go.‘r, 16 go.‘r 12. 5 {H$.‘r./ Vmg 13. `20 14. 12 {Xdg
*****
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Circle-Tangent Properties 225
* {Xboë¶m ‘mnmMr Ordm aMUo.
* g‘mZ Ordm dVw©i‘ܶmnmgyZ g‘mZ A§VamdaAgVmV.
* dVw©iI§S>mVrb H$moZ
* EH$H|$Ðr¶ d EH$ê$n dVw©io
* dVw©imdarb q~XwVyZ ñn{e©Ho$Mr aMZm.* {ÌÁ¶m‘Yrb H$moZ {Xbm AgVm ñn{e©H$m§Mr
aMZm* ~møq~XwVyZ ñn{e©H$m aMZm Am{U {gÕVm.* ñne© H$aUmar dVw©io, AW©, aMZm Am{U
{gÕVm.* g‘mB©H$ ñn{e©H$m DCT Am{U TCT* g‘mB©H$ ñn{e©H$m g‘mB©H$ ~møñn{e©H$m
Am{U Am§Vañn{e©H$m
o.
* MmH$mÀ¶m emoYmZo ‘mZdr OrdZmV ‘hmZ ~XbKSy>Z Ambo AmhoV. MmH$mÀ¶m A^mdmZodmhVyH$, H$maImZo g§nH©$ CnH$aUo B˶mXtMoH$m¶ KS>bo AgVo ¶m§Mr H$ënZm H$am.
* J{UVm‘ܶo dVy©im§À¶m gmhmæ¶mZo ^y{‘VrMmAm{U JVrdmT> H$aUmè¶m J{UVmMm {dH$mghmoʶmg ‘XV Pmbr Amho.
¶m KQ>H$m‘wio Vwåhmbm ¶m§Mo gwb^rH$aU hmoVo.
* R>am{dH$ {ÌÁ¶oÀ¶m dVw©imV R>am{dH$ bm§~rMr Ordm aMUo.
* {dYmZ H$aUo d nS>VmiyZ nmhUo.
(a) g‘mZ Ordm dVw©i‘ܶmnmgyZ g‘mZ A§VamdaAgVmV.
(b) EH$mM dVw©iI§S>mVrb H$moZ g‘mZ AgVmV.
(c) {demb dVw©iI§S>mVrb H$moZ bKwH$moZ AgVmo.
(d) bKw dVw©iI§S>mVrb H$moZ {demb H$moZ AgVmo.
(e) AY©dVw©i I§S>mVrb H$moZ H$mQ>H$moZ AgVmo.
* EH$H|$Ðr¶ d EH$ê$n dVw©io ¶m‘Yrb ’$aH$AmoiIUo.
* N>o{XH$m, Ordm Am{U ñn{e©H$m ¶m‘Yrb ’$aH$.* ñn{e©Ho$À¶m JwUY‘m©Mo {dYmZ H$aUo Am{U nS>VmiUo.* darb {dYmZmÀ¶m ì¶Ë¶mgmMo {dYmZ.* ñne© dVw©im§À¶m AWmªMo ñnï>rH$aU, ~møñne© Am{U
Am§Vañne© H$aVmZm.* ñne© H$aUmè¶m dVw©im§À¶m d, R Am{U r ‘Yrb g§~§Y
AmoiIUo.* VH©$ewÕ nÕVrZo à‘o¶ {gÕ H$aUo.* à‘o¶ Am{U ˶m§Mo ì¶Ë¶mg ¶mda AmYmarV g§»¶mË‘H$
g‘ñ¶m Am{U Cnà‘o¶ gmoS>{dUo.* dVw©imdarb q~XwVyZ ñn{e©H$m aMUo.
* dVw©imbm ~mô¶ q~XþVyZ ñn{e©H$m H$mT>Uo.
* DCT Am{U TCT À¶m JwUY‘mªMo {dYmZ H$aUo.
* {Xboë¶m XmoZ dVw©imZm DCT Am{U TCT aMUo.
* DCT Am{U TCT À¶m bm§~rMo ‘mnZ H$ê$Z nS>VmiyZnhmUo.
The ancient Indian symbol of a circle, with adot in the middle, known as 'bindu', wasprobably instrumental in the use of circle asa representation of the concept zero.
10 dVw©io ( Circles )
dVw©io ( Circles )
dVw©io ( Circles )
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226 UNIT-10
OrdoMo JwUY‘©
Vwåhr dVw©img§~§Yr ì¶m»¶m§Mm (terms) Aä¶mg Ho$bm AmhmV. Imbrb AmH¥$VtMo {ZarjU H$am. nwÝhm ñ‘aU H$amd ì¶m»¶m AmoiIm.
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{Xboë¶m dVw©imV {Xboë¶m ‘mnmMr Ordm aMZo
CXm. 1 … 3 g|.‘r. {ÌOoÀ¶m dVw©imV 5 g|.‘r.bm§~rMr Ordm H$mT>m.
CH$b: nm¶ar 1 … H$mJXmda 'O' dVw©i‘ܶ{ZpíMV H$am. H§$nmg‘ܶo 3 g|.‘r. {ÌOmKodyZ 'O' ‘ܶ H$ënyZ dVw©i H$mT>m.dVw©imÀ¶m n[aKmda 'P' q~Xÿ {ZpíMVH$am.
nm¶ar 2 : 'P' ‘ܶ H$ënyZ 5 g|.‘r.{ÌÁ¶oZo 'Q' ‘ܶo N>oXUmam Mmn ‘mam.P d Q gm§Ym.
åhUyZ 'PQ' hr {Xboë¶m dVw©imVrb 5g|.‘r. bm§~rMr B©ï>> Ordm hmo¶.
CXm. 2 : 2.5 g|.‘r {ÌÁ¶oÀ¶m dVw ©imV4 g|.‘r. bm§~rMr Ordm aMm. Am{U OrdoModVw©i‘ܶmnmgyZ A§Va ‘moOm.
n{hbr 1: 'O' dVw©i‘ܶ Agbobo 2.5g|.‘r. {ÌÁ¶oMo dVw©i H$mT>m. ˶m‘ܶo'LM' = 4 g|.‘r.
Xþgar 2 : 'LM' ¶m OrdoMm ‘ܶq~Xÿ'P' KodyZ 'OP' gm§Ym Am{U nÅ>rZo ‘moOm.
'O' dVw©i‘ܶ d Ordm 'LM' ¶m‘YrbA§Va OP = 1.5 cm.
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5cm
O
LM
P
1.5 cm
4 cm
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Circle-Tangent Properties 227
ñdmܶm¶ 10.1
1. 3.5 g|.‘r. {ÌÁ¶oÀ¶m dV©wimV 6 g|.‘r. bm§~rMr Ordm aMm. dVw©i‘ܶ d Ordo‘Yrb A§Va ‘moOm.2. 4.5 g|.‘r. {ÌÁ¶oÀ¶m dVw©imV 6 g|.‘r. Am{U 8 g|.‘r. bm§~rÀ¶m XmoZ Ordm dVw©i‘ܶmÀ¶m EH$mM
~mOyg H$mT>m. Ord|Mo dVw©i‘ܶmnmgyZMo A§Va ‘moOm.3. 4.5 g|.‘r. {ÌÁ¶oÀ¶m dVw©imV 6.5 g|.‘r. bm§~rÀ¶m XmoZ Ordm dVw©i‘ܶmÀ¶m XmoÝhr ~mOyg H$mT>m.
Ord|Mo dVw©i ‘ܶmnmgyZ A§Va ‘moOm.4. 5 g|.‘r. {ÌÁ¶oÀ¶m dVw©imV 9 g|.‘r. Am{U 7 g|.‘r. bm§~rÀ¶m XmoZ Ordm dVw©i‘ܶmÀ¶m XmoÝhr
~mOyg H$mT>m OrdoMo dVw©i‘ܶmnmgyZ A§Va ‘moOm.
dVw©imÀ¶m Ordoer g§~§{YV JwUY‘©
Imbrb AmH¥$˶m§Mo {ZarjU H$am Am{U à˶oH$ AmH¥$VrÀ¶m ~m~VrV OrdoMr bm§~r, dVw©i ‘ܶmnmgyZ OrdoMoA§Va H$mT>m.
AmH¥$Vr 1 AmH¥$Vr 2 AmH¥$Vr 3
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OM
KJ
I
V
Ordm AB = Ordm EF = Ordm IJ =
Ordm CD = Ordm GH = Ordm KL =
Ordm MN =
b§~m§Va b§~m§Va b§~m§Va
OP = OR = OT =
OQ = OS = OU =
OV =
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228 UNIT-10
à˶oH$ KQ>ZoVrb Ord|Mr bm§~r d dVw©i‘ܶmnmgyZMo b§~m§Va ¶m§Mr VwbZm H$am. Amnbm AZw‘mZ H$m¶?
• EH$mM dVw©imVrb g‘mZ Ordm dVw©i‘ܶmnmgyZ g‘mZ A§Vamda AgVmV.
dVw©im‘ܶo AZoH$ Ordm H$mT>Vm ¶oVmV. ˶m OrdoMo A§Va g‘mZ Agob Va ˶m Ordm dVw©i‘ܶmnmgyZ g‘mZA§Vamda AgVmV. hm ì¶Ë¶mg Iam Amho.
• Oa EImÚm dVw©imV dVw©i‘ܶmnmgyZ g‘mZ A§Vamda H$mT>boë¶m Ordm g‘mZ AgVmV.
AmVm Ordm d dVw©i‘ܶ ¶m‘Yrb b§~m§Va dmT>Vo qH$dm H$‘r hmoVo ¶mMm Aä¶mg H$ê$.
• Imbrb AmH¥$VtMo {ZarjU H$am Ordm Am[U dV©wi‘ܶmnmgyZMo A§Va ¶m§À¶m qH$‘VrMm Vº$m nyU© H$am.
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E P BAY
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OrdoMr bm§~r dVw©i‘ܶmnmgyZMo b§~m§Va
1. DC = OQ =
2. EF = OR =
3. AB = OP =
4. XY =
darb V³Ë¶mVrb ‘m{hVrdê$Z Ago {gÕ hmoVo H$s,
(a) Oer OrdoMr bm§~r dmT>Vo Vgo dVw©i‘ܶmnmgyZMo A§Va..............
(b) Oer OrdoMr bm§~r H$‘r Vgo dVw©i‘ܶmnmgyZMo A§Va..............
(c) dVw©imVrb gdm©V ‘moR>r Ordm Am{U dVw©i‘ܶ ¶m‘Yrb A§Va..............
åhUyZ Amåhr Agm {ZîH$f© H$mT>Vmo H$s,
Oa OrdoMr bm§~r OgOer OmñV hmoVo Vgo dVw©i‘ܶmnmgyZMo A§Va H$‘r hmoVo.
Oa OrdoMr bm§~r OgOer H$‘r hmoVo Vgo dVw©i‘ܶmnmgyZMo A§Va OmñV hmooVo.
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Circle-Tangent Properties 229
dVw©im§Mo I§S> (SEGMENT OF CIRCLES)
Imbrb AmH¥$VtMo {Z[ajU H$am Am{U ˶mImbrb àým§Mr CÎma Úm.
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PQ
SAmH¥$Vr -1 AmH¥$Vr -2
1. Am.Z§. 1 ‘ܶo … bKwH§$g d {dembH§$g AmoiIm d Zm§do gm§Jm.
2. Am.Z§. 2 ‘ܶo … PRQ H$moU Amho?
3. darb AmH¥$Vr‘ܶo bKwdVw©iI§S>, {demb dVw©iI§S> d AY©dVw©i I§S>m§Mr Zm§do {bhm.
dVw©iI§S>mVrb H$moZ (Angles in a segment)
~mOyÀ¶m AmH¥$VrMo {ZarjU H$am.
'O' dVw©i‘ܶ Agboë¶m dVw©imV 'XY' hr Ordm. XZYX hm bKwdVw©i I§S>Am{U XAYX hm {dembdVw©i I§S> Amho.
XPYÐ Am{U XQYÐ ¶mMo {ZarjU H$am.
Voìhm Ago gm§JVm ¶oB©b H$s, XPYÐ hm AYX {dembdVw©i I§S>mVrb H$moZd XQYÐ hm XZYX bKwdVw©i I§S>mVrb H$moZ AmhoV.
¶mdê$Z dVw©iI§S>mVrb H$moZm§Mo JwUY‘© {gÕ H$aVm ¶oVrb.
H¥$Vr 1 … Imbrb AmH¥$˶m§‘Yrb bKwdVw©i I§S>mVrb H$moZm§Mo {ZarjU H$am, H$moZ ‘moOm d H$moZm§Mr ‘mno ImbrbaH$mݶmV ^am.
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A
C
D
OA
CB
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230 UNIT-10
AmH¥$Vr bKwdVw©i I§S>mVrb H$moZ H$moZmMm àH$ma
1. Ð =ADC
2. Ð =ABC
darb ‘mnmdê$Z Ago {gÕ hmoVo H$s,
H$moU˶mhr dVw©im‘ܶo bKwdVw©i I§S>mVrb H$moZ {dembH$moZ AgVmo.
H¥$Vr 2 … Imbrb AmH¥$˶m§Mo {ZarjU H$am, H$moZ ‘moOm Am{U H$moZm§Mr ‘mno aH$mݶmV ^am.
P Q
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AmH¥$Vr 1 AmH¥$Vr2
AmH¥$Vr {dembdVw©i I§S>mVrb H$moZ H$moZmMm àH$ma
1. RPQ =
2. LKN =
darb ‘mnmdê$Z Ago {gÕ hmoVo H$s,
H$moU˶mhr dVw©im‘ܶo {dembdVw©i I§S>mVrb H$moZ bKwH$moZ AgVmo.
H¥$Vr 3 … Imbrb AmH¥$˶m§Mo {ZarjU H$am, H$moZ ‘moOm Am{U H$moZm§Mr ‘mno aH$mݶmV ^am.
OX
Z
YP
O
P
Q
S
R
AmH¥$Vr -1 AmH¥$Vr -2
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Circle-Tangent Properties 231
AmH¥$Vr AY© dVw©iI§S>mVrb H$moZ H$moZmMm àH$ma
1 XYZÐ =
2 PSQÐ =
darb ‘mnmdê$Z Ago {gÕ hmoVo H$s,
AY© dVw©iI§S>mVrb H$moZ H$mQ>H$moZ AgVmo.
H¥$Vr 4 … H$moZ ‘moOm Am{U H$moZm§Mr ‘mno Imbr {Xboë¶m aH$mݶmV ^am.
Imbr {Xboë¶m VrZ dVw©imMo {ZarjU H$am.
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P QR
S
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O
A
C
D
E
B
HIG
X
Y
O
(i) (ii) (iii)
AmH¥$Vr EH$mM dVw©iI§S>mVrb H$moZ {ZîH$f©
i PQTÐ = PRTÐ = PSTÐ =
i i ACBÐ = ADBÐ = AEBÐ =
ii i XGYÐ = XHYÐ = XIYÐ =
darb V³Ë¶mdê$Z Ago {gÕ hmoVo H$s, EH$mM dVw©iI§S>mVrb H$moZ g‘mZ AgVmV.
* bKw dVw©iI§S>mVrb gd© {dembH$moZ g‘mZ AgVmV
* {demb dVw©iI§S>mVrb gd© bKwH$moZ g‘mZ AgVmV
* AY© dVw©iI§S>mVrb gd© H$mQ>H$moZ g‘mZ AgVmV
Agm {ZîH$f© {ZKVmo H$s,
EH$mM dVw©iI§S>mVrb gd© H$moZ Zoh‘r g‘mZ AgVmV.
EH$H|$Ðr¶ qH$dm g‘H|$Ðr¶ dVy©io (CONCENTRIC CIRCLES) :
Imbrb AmH¥$VrMo {ZarjU H$am d Imbrb àým§Mr CÎmao {bhm.
AmH¥$Vr 1 AmH¥$Vr 2 AmH¥$Vr 3
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232 UNIT-10
O A
B
CD
C1
C2
C3
C4
1. C1, C2, C3 d C4 ¶m AmH¥$˶m H$m¶ AmhoV?
2. 'O' dVw©iH|$Ðm~m~V Vw‘Mm {ZîH$f© H$m¶?
3. OA, OB, OC, OD ‘moOm? d ˶m g‘mZ AmhoV H$m?
darb àým§À¶m CÎmamdê$Z Ago {gÕ hmoVo H$s,-
doJdoJù¶m {ÌÁ¶m nU dVw©iH|$Ð EH$M AmhoV. Vr EH$H|$Ðr¶ qH$dm g‘H|$Ðr¶ dVw©io AmhoV.
{ÌÁ¶m {^Þ na§Vw g‘mZ H|$Ð AgUmè¶m dVw©imZm EH$H|$Ðr¶ qH$dm g‘H|$Ðr¶ dVw©io Ago åhUVmV.
EH$ê$n dVw©io (Congruent circles) :
Imbrb AmH¥$VtMo {ZarjU H$am. C1, C2 Am{U C3 ¶m dVw©im§À¶m {ÌÁ¶m ‘moOm, ˶m g‘mZ AmhoV, nU dVw©i H|$БmÌ {^Þ AmhoV.
A B
C1
C D
C2
E F
C3
{ÌÁ¶m g‘mZ na§Vw {^Þ H|$Ð AgUmè¶m dVy©im§Zm EH$ê$n dVy©i åhUVmV.
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Circle-Tangent Properties 233
ñdmܶm¶ 10.2
1. 'O' dVw©i‘ܶ KodyZ AZwH«$‘o 1.5 g|.‘r., 2.5 g|.‘r. d 3.5 g|.‘r. {ÌÁ¶oMr 3 EH$H|$Ðr¶ dVw©io H$mT>m.
2. O1 d O2 dVw©i‘ܶ AgUmar Am{U 3 g|.‘r. g‘mZ {ÌÁ¶oMr dVw©io H$mT>m. XmoÝhr dVw©i‘ܶmVrb A§Va 5g|.‘r. Amho.
3. AB = 8 g|.‘r. aofmI§S> H$mTy>Z 'C' hm ˶mMm ‘ܶq~Xÿ ¿¶m. 2 g|.‘r. {ÌÁ¶m KodyZ AZwH«$‘o A, B Am{U Cho dVw©i‘ܶ AgUmar VrZ dVw©io H$mT>m. 'C' dVy©i‘ܶ H$ënyZ 4 g|.‘r.Mo AmUIr EH$ dVw©i H$mT>m. ¶m‘ܶoEH$H|$Ðr¶ d EH$ê$n dVw©io AmoiIm.
4. 4 g|.‘r. {ÌÁ¶oÀ¶m dVw©imV 6 g|.‘r. bm§~rMr Ordm H$mT>m. XmoÝhr dVw©iI§S>mV 2 bKwH$moZ d 2 {dembH$moZaMm. Am{U {demb dVw©iI§S>mVrb H$moZ bKwH$moZ Am{U bKwdVy©i I§S>mVrb H$moZ {dembH$moZ AgVmo ho‘moOyZ nS>Vmim.
5. 3.5 g|.‘r. {ÌÁ¶oÀ¶m ‘O’ dVw©i‘ܶ AgUmè¶m dVw©imMm AOB hm ì¶mg H$mT>m. ì¶mgmÀ¶m XmoÝhr ~mOybmH$moZ Am§VarV H$am Am{U AY© dVw©iI§S>mVrb H$moZ H$mQ>H$moZ AgVmV ho ‘moOm Am{U nS>Vmim.
****
Circle - chord properties
Construction of chords ofgiven length
Verification ofproperties Concentric
CirclesCongruent
Circles
Chord propertyConstruction
acute anglesEqual chords areequidistant from
the centre Minor segment
Semi circle
obtuse angles
Equal
dVw©io - Á¶m- JwUY‘©
{Xboë¶m bm§~rMr Á¶m aMZo JwUY‘mªMm nS>Vmimg‘H|$Ð dVw©io
aMZmÁ¶m JwUY‘©
g‘mZ bm§~rÀ¶m Á¶mdVw©i ‘ܶmnmgyZ g‘mZ
A§Vamda AgVmV
{demb I§S>
bKw I§S>
I§S>mVrb H$moZ
AY© dVw©i
g‘mZ
H$mQ>H$moZ
{demb H$moZ
bKwH$moZ
EH$ê$n dVw©io
g‘mZ dVw©iI§S>
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234 UNIT-10
ñn{e©Ho$Mo JwUY‘©
‘mJrb àH$aUm‘ܶo Vwåhr dVw©imÀ¶m OrdoÀ¶m JwUY‘m©{df¶r Aä¶mg Ho$bobm AmhmV. ¶m àH$aUm‘ܶo AmnUdVw©imÀ¶m H$m§hr A{YH$ JwUY‘mªMm Aä¶mg H$ê$.
Oa dVw©i Am{U gaiaofm EH$mM nmVirV H$mT>boë¶m AgVrb Va Imbr Xe©{dë¶mà‘mUo VrZ e³¶VmAmT>iVmV.
AmH¥$Vr 1 AmH¥$Vr 2 AmH¥$Vr 3
N>o{XH$m : dVw©imbm XmoZ doJdoJù¶m q~XÿV N>oXUmè¶m gaiaofobm N>o{XH$m Ago åhUVmV.
ñn{e©H$m : dVw©imbm ’$º$ EH$mM q~XÿV ñne© H$aUmè¶m gaiaofobm ñn{e©H$m Ago åhUVmV.
Imbrb AmH¥$˶m§Mo {ZarjU H$am. dVw©imbm ’$º$ EH$mM q~XÿV ñn{e©H$m ñne© H$aVo.
PO
B
A
O
QC D
E
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R
FO
G S H
'O' ‘ܶ Agboë¶m dVw©imZm AB , CD , EF Am{U GH ¶m H$mT>boë¶m ñn{e©H$m AmhoV. P, Q, R
Am{U S ho ñne©q~Xÿ qH$dm ñn{e©Ho$Mo q~Xÿ AmhoV.
ñne©q~Xÿ : Á¶m q~XÿV ñn{e©H$m dVw©imbm ñne© H$aVo ˶mbm ñne©q~Xÿ Ago åhUVmV.
* RQ gaiaofm dVw©imbm ñne© H$aVZmhr.
* RQ hr dVw©imbm Z N>oXUmar aofmAmho.
* RQ gaiaofm dVw©imbm A Am{UB ‘ܶo N>oXVo.
* RQ bm dVw©imMr N>o{XH$m AgoåhUVmV.
* RQ gaiaofm hr dVw©imbm P ¶mEH$ Am{U ’$º$ EH$mM q~XÿV ñne©H$aVo.
* RQ bm dVw©imMr P Vrb ñn{e©H$m
Ago åhUVmV.
O
Q
R
B
AO
Q
R
O
Q
R
P
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Circle-Tangent Properties 235
Imbrb CXmhaUmMo {ZarjU H$am. dVw©io Am{U ˶m§À¶m ñn{e©H$m Xe©{dUmè¶m X¡Z§{XZOrdZmVrb dñVy {Xboë¶m AmhoV.
CXmhaU 1 : ¶oWo H$ßnr (pulley) dVw©i Xe©{dVo.AB Am{U CD ¶m Vmam H$ßnrÀ¶m ñn{e©H$m Xe©{dVmV.
CXmhaU 2 : O{‘Zrdarb EHo$ar gm¶H$b MmH$mMo {ZarjU H$am. gm¶H$brMo MmH$ hodVw©i Xe©{dVo Am{U O{‘Zrdarb gm¶H$brMm {’$aʶmMm ‘mJ© ho MmH$mMr ñn{e©H$m Xe©{dVo.
ñn{e©Ho$Mo JwUY‘© :AmVm AmnU dVw©imÀ¶m ‘hËdmÀ¶m ñn{e©Ho$À¶m JwUY‘m©~Ôb {eHy$.
H¥$Vr 1 : {Xboë¶m AmH¥$VtMo {ZarjU H$am Am{U Imbrb gmaUr nyU© H$am.
AmH¥$Vr 1 AmH¥$Vr 2 AmH¥$Vr 3
O
X YP
K
L
M
NA
B
C
D
AmH¥$Vr 1 AmH¥$Vr 2 AmH¥$Vr 3
1. {ÌÁ¶m
2. ñn{e©H$m
3. ñne©q~Xÿ
4.{ÌÁ¶m Am{U ñn{e©H$m ¶m‘Yrb H$moZ(H$moZ ‘mnH$mÀ¶m ghmæ¶mZo H$moZ ‘moOm.)
darb {ZarjUmdê$Z Amåhr Agm {ZîH$f© H$mT>Vmo H$s,
H$moU˶mhr dVw©imV ñne©q~XþVyZ H$mT>bobr {ÌÁ¶m ñn{e©Ho$bm b§~ AgVo.
H¥$Vr 2 … Imbrb AmH¥$VtMo {ZarjU H$am. H$moZ ‘moOm Am{U {Xboë¶m gmaUrV {bhm.
A D
CB
AmH¥$Vr 1 AmH¥$Vr 2 AmH¥$Vr 3
A
B
PO
P
A
B
O
O B
A P
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236 UNIT-10
Imbrb àým§Mr CÎmao gm§Jm …
1. H$moU˶m AmH¥$VrVrb OP {ÌÁ¶m hr AB bm b§~Amho?
2. {Vgè¶m AmH¥$VrVrb AB bm H$m¶ åhUVmV?
3. H$moU˶m AmH¥$VrVrb AB ñn{e©H$m Amho? H$m?
H¥$Vr 2 dê$Z Amåhr Agm {ZîH$f© H$mT>Vmo H$s dVw©im‘ܶo {ÌÁ¶oÀ¶m H|$Ð Zgboë¶m A§Ë¶ q~XÿVH$mT>bobm b§~ hr dVw©imMr ñn{e©H$m AgVo.
ho ¶m nwdu Z‘yX Ho$boë¶m ñn{e©Ho$À¶m JwUY‘m©À¶m ì¶Ë¶mgmMo {dYmZ Amho.
dVw©imdarb (narKmdarb) q~XþVyZ ñn{e©H$m aMUo.
CXmhaU 1 … 3 g|.‘r. {ÌÁ¶oÀ¶m dVw©imdarb P bm H$moU˶mhr q~XþVyZ ñn{e©H$m H$mT>m.
nm¶ar 1 … 3 g|.‘r. {ÌÁ¶oMo 'O' ‘ܶAgUmao dVw©i H$mT>m. dVw©imÀ¶m narKmdaq~Xÿ P Mr IwU H$am. OP gm§Ym.
nm¶ar 2 … {ÌÁ¶oÀ¶m g‘mZ AgUmamOP H§$g H$mT>bm AgVm OP bm O Am{UdVw©imbm A ‘ܶo N>oXVmo.
nm¶ar 3 … H§$gmda B hr IwUAer H$am H$s OA = ABhmoB©b.˶M {ÌOoZo ‘mZyZ XmoZ N>oXUmaoMmn H$mT>.
nm¶ar 4 … PC gm §Ym Am {UAmdí¶H$ ñn{e©H$m {‘i{dʶmgmR>rdmT>dm.
H$moZ AmH¥$Vr 1 AmH¥$Vr 2 AmH¥$Vr 3
1. OPA ........... ........... ........... 2. OPB ........... ........... ...........
g |. ‘ r§.3O P
A
g |. ‘ r§.3O P
A B
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CXmhaU 2 … 2 g|.‘r. {ÌÁ¶oMo dVw©i H$mT>m Am{U XmoZ {ÌÁ¶o§À¶m dVw©i‘ܶ Zgboë¶m A§Ë¶q~XÿVyZñn{e©H$m§À¶m OmoS>rMr Aer aMZm H$am H$s XmoÝhr {ÌÁ¶m§‘Yrb H$moZ 100° hmoB©b. ñn{e©H$m§‘Yrb H$moZ ‘moOm.
{Xbobo … dVw©imMr {ÌÁ¶m = r = 2 g|.‘r. ñn{e©H$m‘Yrb H$moZ = 100°
nm¶ar 1 … 2 g|.‘r. {ÌÁ¶oMo O ‘ܶo nm¶ar 2 … P ‘YyZ ñn{e©H$m H$mT>m.AgUmao dVw©i H$mT>m. ˶mdaP Mr IwU H$am Am{U OP gm§Ym.
nm¶ar 3 … O ‘ܶo POQ =100° H$mT>m. nm¶ar 4 … 'Q' ‘ܶo Xþgar ñn{e©H$m H$mT>m.ñn{e©Ho$‘Yrb H$moZ ‘moOm.
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ñn{e©H$o‘Yrb H$moZ 80º Amho.
{ZarjU H$am H$s dVw©im‘ܶo {ÌÁ¶m§‘Yrb Am{U ñn{e©H$m§‘Yrb H$moZ nyaH$ AgVmV.
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CXmhaU 3 … 2.5 g|.‘r. {ÌÁ¶oÀ¶m dVw©imV 4 g|.‘r. bm§~rMr Ordm H$mT>m. OrdoÀ¶m A§Ë¶ q~XyVyZ ñn{e©H$m H$mT>m.
{Xbobo … r = 2.5 g|.‘r., OrdoMr bm§~r = 4 g|.‘r.
nm¶ar 1 … 2.5 g|.‘r. {ÌÁ¶oMo nm¶ar 2 … 4 g|.‘r. bm§~rMr AB Ordm H$mT>m.'O' ‘ܶ AgUmao dVw©i H$mT>m.
nm¶ar 3 … OA Am{U OB.gm§Km nm¶ar 4 … A Am{U B ‘YyZ dVw©imbmñn{e©H$m H$mT>m.
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Cn{gÕm§V …
1. ñne© q~XþVyZ ñn{e©Ho$bm H$mT>bobm b§~ hm dVw©i‘ܶmVyZ OmVmo.
2. dVw©imdarb H$moU˶mhr q~XþVyZ ’$º$ EH$M ñn{e©H$m H$mT>Vm ¶oVo.
3. ì¶mgmÀ¶m A§Ë¶q~XþVyZ H$mT>boë¶m ñn{e©H$m EH$‘oH$m§Zm g‘m§Va AgVmV.
darb VrZ {dYmZm§Mr dJm©‘ܶo gH$maU MMm© H$am Am{U ñnï>rH$aU Úm.
ñdmܶm¶ 10.3
1. 4 g|.‘r. {ÌÁ¶oMo dVw©i H$mT>m Am{U dVw©imdarb H$moU˶mhr q~XþVyZ ñn{e©H$mH$mT>m.
2. 7 g|.‘r. ì¶mgmMo dVw©i H$mT>m Am{U ì¶mgmÀ¶m A§Ë¶ q~XþVyZ ñn{e©H$m H$mT>m.
3. 3.5 g|.‘r. {ÌÁ¶oÀ¶m dVw©imV nañnam§er b§~ AgUmao XmoZ ì¶mg H$mT>m. ì¶mgm§À¶m A§Ë¶ q~XwVyZ ñn{e©H$mH$mT>m.
4. 4.5 g|.‘r. {ÌÁ¶oÀ¶m dVw©imV XmoZ {ÌÁ¶m Aem H$mT>m H$s, ˶m‘Yrb H$moZ 70° Mm hmoB©b. {ÌÁ¶oÀ¶m dVw©iH|$Ð Zgboë¶m A§Ë¶ q~XþVyZ ñn{e©H$m H$mT>m.
5. 3 g|.‘r. {ÌÁ¶oMo dVw ©i H$mT> m Am{U ˶mbm Xm oZ ñn{e©H$m Aem H$mT>m H$s, ˶m‘Yrb H$m oZ40° Mm hmoB©b.
6. 4.5 g|.‘r {ÌÁ¶oMo dVw©i H$mT>m Am{U ˶mV 7 g|.‘r. bm§~rMr PQ Ordm H$mT>m. P ‘YyZ ñn{e©H$m H$mT>m.
7. 5 g|.‘r {ÌÁ¶oÀ¶m dVw©imV 8 g|.‘r. bm§~rMr Ordm H$mT>m. OrdoÀ¶m A§Ë¶ q~XþVyZ ñn{e©H$m H$mT>m.
8. 4 g|.‘r. {ÌÁ¶oMo dVw©i H$mT>m Am{U ˶mV 6 g|.‘r. bm§~rMr Ordm H$mT>m. dVw©i‘ܶmVyZ Ordobm b§~AgUmar {ÌÁ¶m H$mT>m. OrdoÀ¶m Am{U {ÌÁ¶oÀ¶m A§Ë¶ q~XþVyZ ñn{e©H$m H$mT>m.
9. 3.5 g|.‘r. {ÌÁ¶oMo dVw ©i H$mT>m Am{U ˶mM H§$gmZo Am§VarV Ho$bobm 80° Mm H|$ÐñW H$moZ H$mT>m.dVw©imdarb q~XþVyZ ñn{e©H$m H$mT>m. ñn{e©H$m EH$‘oH$m§Zm N>oXVrb Aem[aVrZo nwT>o dmT>dm. Vwåhr H$m¶{ZarjU H$amb?
10. 4.5 g|.‘r. {ÌÁ¶oÀ¶m dVw©imV 5 g|.‘r. bm§~rÀ¶m XmoZ g‘mZ Ordm dVw©i‘ܶmÀ¶m XmoÝhr ~mOyg H$mT>m.OrdoÀ¶m A§Ë¶q~XþVyZ ñn{e©H$m H$mT>m.
doJdoJù¶m pñWVrVrb q~XþVyZ dVw©imbm ñn{e©H$m H$mT>Uo …1. dVw©imdarb q~Xy …
H¥$Vr 1 … 3 g|.‘r. {ÌÁ¶oMo dVw©i H$mT>m Am{U ˶mda q~Xÿ P hr IwU
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H$am. P ‘YyZ dVw©imbm ñn{e©H$m H$mT>m. P ‘YyZ Xþgar ñn{e©H$mH$mT>ʶmMm à¶ËZ H$am. ho e³¶ Amho? H$m? dVw©imdarb H$moU˶mhrq~XþVyZ dVw©imbm ’$º$ EH$M ñn{e©H$m H$mT>Vm ¶oVo ho Vwåhr ¶mnyduAä¶mgbm AmhmV.
2. dVw©im‘Yrb q~Xÿ …
H¥$Vr 2 … 3 g|.‘r. {ÌÁ¶oMo Xþgao EH$ dVw©i H$mT>m. dVw©im‘ܶo q~Xÿ Phr IwU H$am. ¶m q~XþVyZ dVw©imbm ñn{e©H$m H$mT>Uo e³¶ Amho? Vwåhmbm Ago {XgyZ ¶oVo H$s øm q~XþVyZ H$mT>bobr à˶oH$ aofmdVw©imbm XmoZ doJdoJù¶m q~XÿV N>oXVo. øm gd© gaiaofm dVw©imÀ¶mN>o{XH$m AmhoV.
3. dVw©im~mhoarb q~Xÿ …
H¥$Vr 3 … 3 g|.‘r. {ÌÁ¶oMo dVw©i H$mT>m. dVw©im~mhoaq~Xÿ P Mr IwU H$am. øm q~XþVyZ dVw©imH$S>o {H$aUH$mT>m. ˶m§Mo {ZarjU H$am. P ‘YyZ OmUmè¶m {H$VrN>o{XH$m dVw©imbm H$mT>Vm ¶oVmV?
P ¶m ~mø q~XþVyZ {H$Vr ñn{e©H$m dVw©imbm H$mT>Vm ¶oVmV?
AmH¥$Vrdê$Z Vwåhmbm Ago {XgyZ ¶oVo H$s ’$º$ PQAm{U PR ho dVw©imbm ñne© H$aVmV. dVw©imbm P ‘YyZH$mT>boë¶m øm ñn{e©H$m AmhoV.
~møq~XþVyZ dVw©imbm ’$º$ XmoZ ñn{e©H$m H$mT>Vm ¶oVmV.
~mø q~XþVyZ dVw©imbm H$mT>boë¶m XmoZ ñn{e©Ho$Zm Img AgoJwUY‘© AgVmV. Imbrb H¥$VrÛmao ˶m JwUY‘m©Zm Vwåhr emoYy eH$mb.
Imbr [Xboë¶m AmH¥$VtMo {ZarjU H$am Am{U Imbrb àým§MrCÎmao gm§Jm. (Úm)
(a) 'P' ¶m ~møq~XþVyZ dVw©imbm H$mT>boë¶m ñn{e©Ho$Mr Zm§do {bhm.
(b) PA Am{U PB ‘moOm. Vw‘Mo AZw‘mZ H$m¶ Amho?
(c) H$moZ ‘mnH$mMm Cn¶moJ H$ê$Z AOP Am{U BOP ‘moOm.
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(d) APO Am{U BPO ‘moOm. H$moU˶m {R>H$mUr H$moZ V¶ma Pmbobo AmhoV?{Xboë¶m gmaUr‘ܶo ‘moO‘mnm§Mr Zm|X H$am.
AmH¥$Vr I II III
1. PA = ....... AOP = ....... AOP = ......
PB = ....... BOP = ....... BOP = ......
2. PA = ....... AOP = ....... AOP = ......
PB = ....... BOP = ....... BOP = ......
darb ‘m{hVrÀ¶m {ZarjUmZ§Va Imbrb {dYmZo nyU© H$am.
1. ~mø q~XþVyZ dVw©imbm H$mT>boë¶m ñn{e©H$m ........ g‘mZ AgVmV.
2. ~mø q~XþVyZ dVw©imbm H$mT>boë¶m ñn{e©H$m dVw©i H|$Ðmer ........ H$moZ Am§VarV H$aVmV.
3. dVw©imbm ~møq~XþVyZ H$mT>boë¶m ñn{e©H$m dVw©i‘ܶ Am{U ~møq~Xÿ ¶m§Zm gm§YUmè¶m aofoer ........ H$moZAm§VarV H$aVmV.
darb H¥$Vrdê$Z Vwåhr Agm {ZîH$f© H$mT>mb H$s, dVw©imbm ~møq~XþVyZ H$mT>boë¶m ñn{e©H$m
(a) g‘mZ AgVmV.
(b) dVw©i‘ܶmer g‘mZ H$moZ Am§VarV H$aVmV.
(c) dVw©i‘ܶ Am{U ~mø [~§Xÿ ¶m§Zm gmYUmè¶m aofoer g‘mZ H$moZ Am§VarV H$aVmV.
dVw©imbm ~mø q~XþVyZ H$mT>boë¶m ñn{e©Ho$Mo JwUY‘© Amåhr àm¶mo{JH$ aMZm Am{U ‘moO‘mnmZo Aä¶mgbmoAmhmoV. AmVm AmnU øm JwUY‘m©À¶m Vm{H©$H$ {gÕVoMr MMm© H$ê$. nU Vm{H©$H$ {gÕVobm Omʶmnydu Imbrbàým§Mr CÎmao {bhm. dJm©‘ܶo MMm© H$am. ¶m§Mr Vwåhmbm à‘o¶ {gÕ H$aʶmg ‘XV hmoB©b.
1. OPB Am{U OQB ho H$moU˶m àH$maMo H$moZ AmhoV?
2. dVw©imMm {dMma Ho$ë¶mg OP Am{U OQ ho H$m¶ AmhoV?
3. OPB Am{U OQB ho H$moU˶m àH$maMo {ÌH$moU AmhoV?
4. OPB Am{U OQB Mm {dMma Ho$ë¶mg OB hr H$m¶ Amho?
5. OPB Am{U OQB ho EH$‘oH$m§er EH$ê$n AmhoV?
6. H$moU˶m J¥hrVH$mZwgma OPB Am{U OQB ho EH$ê$n AmhoV?
AmVm AmnU Vm{H©$H$ ÑîQ>çm à‘o¶ {gÕ H$ê$.
à‘o¶ … dVw©imbm ~møq~XþVyZ H$mT>boë¶m ñn{e©H$m.
(a) g‘mZ AgVmV.
(b) dVw©i‘ܶmer g‘mZ H$moZ Am§VarV H$aVmV.
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(c) dVw©i‘ܶ Am{U ~møq~Xÿ gm§YUmè¶m aofoer g‘mZ H$moZ Am§VarV H$aVmV.
J¥hrV : A hm dVw©imMm ‘ܶ Amho, B hm ~møq~Xÿ Amho.
BP Am{U BQ øm ñn{e©H$m AmhoV.
AP , AQ Am{U AB OmoS>bobo AmhoV.
gmܶ : (a) BP = BQ
(b) PAB = QAB(c) PBA = QBA
{gÕVm : {dYmZ H$maU
APB Am{U AQB ‘ܶo
AP = AQ (EH$mM dVw©imÀ¶m {ÌÁ¶m)
APB = AQB = 90° (ñne© q~XþVyZ dVw©imbm H$mT>bobr
{ÌÁ¶m ñn{e©Ho$bm b§~ AgVo.)
H$U© AB = H$U© AB (g‘mB©H$ ~mOy)
APB AQB (H$m H$ ~m à‘o¶) (R.H.S) (a) PB = QB CPCT
(b) PAB = QAB
(c) PBA = QBA
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1 … AmH¥$Vr‘ܶo ABCD Mm¡H$moZmV dVw©i Am§Va{bIrV Ho$bobo Amho. B = 90°. Oa AD = 23 g|.‘r,AB = 29 g|.‘r. Am{U DS = 5 g|.‘r. Va dVw©imMr {ÌÁ¶m H$mT>m.
CH$b…AmH¥$Vr‘ܶo AB, BC, CD Am{U DA øm dVw©imbm AZwH«$‘o Q, P, S Am{U R ‘YyZ H$mT>boë¶mñn{e©H$m AmhoV.
DS = DR dVw©imbm 'D' ¶m ~møq~XþVyZ H$mT>boë¶m ñn{e©H$m AmhoV.
na§Vw DS = 5 g|.‘r. ({Xbobo)
DR = 5 g|.‘r.
AmH¥$Vr‘ܶo AD = 23 g|.‘r. ({Xbobo)
AR = AD – DR = 23 – 5 = 18 g|.‘r.
na§Vw AR = AQ (dVw©imbm A ¶m ~møq~XþVyZH$mT>boë¶m ñn{e©H$m AmhoV.)
AQ = 18 g|.‘r.
Oa AQ = 18 g|.‘r. Va ( AB = 29 g|.‘r. {Xbobo Amho.)
BQ = AB – AQ = 29 – 18 = 11 g|.‘r.
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BQOP Mm¡H$moZm‘ܶo
BQ = BP (B ¶m ~møq~XþVyZ H$mT>boë¶m ñn{e©H$m)
OQ = OP (EH$mM dVw©imÀ¶m {ÌÁ¶m)
QBP = QOP = 90° {Xbobo
OQB = OPB = 90° (ñn{e©Ho$Mm ñne© q~Xÿ Am{U {ÌÁ¶m ¶m‘Yrb H$moZ)
BQOP hm Mm¡ag Amho.
dVw©imMr {ÌÁ¶m = OQ = 11 g|.‘r.
CXmhaU 2 … AmH¥$Vr‘ܶo P ¶m ~møq~XþVyZ H$mT>boë¶m AP Am{U BP øm ñn{e©H$m AmhoV. AOB Am{UAPB nyaH$ H$moZ AmhoV ho {gÕ H$am.
CH$b … J¥hrV … 'O' hm dVw©imMm ‘ܶ Amho. 'P' ¶m ~møq~XþVyZ H$mT>boë¶m AP Am{U BP øm ñn{e©H$m AmhoV.
gmܶ … AOB + APB = 180°
{gÕVm … Mm¡H$moZm‘ܶo AOBP
AOB + OBP + BPA + PAO = 360°
nU OBP = 900 Am{U OAP= 90°
AOB + 900 + BPA + 900 = 360°
AOB + BPA + 1800 = 360°
AOB + BPA = 360° – 180°
AOB + BPA = 1800
AOB Am{U BPA ho nyaH$ H$moZ AmhoV.
CXmhaU 3 …AmH¥$Vr‘ܶo 'O' ‘ܶ Agboë¶m dV©wimbm PQ Am{U PR ¶m ñn{e©H$m AmhoV.
Oa P =45
O Va O Am{U P H$mT>m.
CH$b … AmH¥$Vr‘ܶoQPR + QOR = 180°
( {dê$Õ H$moZ nyaH$ AgVmV.)
na§Vw, QPR =45
QOR
45
QOR + QOR = 180°
4 QOR + 5 QOR5
= 180°
9 QOR = 5 × 180°
QOR=5 180
0
9 90 = 100°
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Oa QOR = 100° Va QPR = 180° – QOR = 180° – 100° = 80°
QPR = 80°
CXmhaU 4 … AmH¥$Vr‘ܶo 'O' hm dVw©imMm ‘ܶ Amho. B Am{U D ‘Yrb ñn{e©H$m EH$‘oH$m§Zm P q~XÿV N>oXVmV.Oa AB hr CD bm g‘m§Va Amho Am{U ABC = 55° Va (i) BOD (ii) BPD H$mT>m.
CH$b … AmH¥$Vr‘ܶo AB || CD {Xbobo
ABC = BCD ( ì¶wËH«$‘ H$moZ
na§Vw ABC = 55° ( {Xbobo)
BCD = 55°
AmH¥$Vr‘ܶo BOD = 2 BCD (H|$ÐñW H$moZ hm n[aKñW H$moZmÀ¶mXþßnQ> Amho.
BOD = 2 × 55° = 110°.
na§Vw BOD + BPD = 180°
BPD = 180° – BOD = 180° – 110° = 70
CXmhaU 5 … AmH¥$Vr‘ܶo ABC Mr n[a{‘Vr = 2 (AP + BQ + CR) AgoXmIdm.
CH$b … ABC Mr n[a{‘Vr = AB + BC + AC
= AP + PB + BQ + QC + CR + RA
nU AP = AR (dVw©imbm A ‘YyZ H$mT>boë¶m ñn{e©H$m)
PB = BQ (dVw©imbm B ‘YyZ H$mT>boë¶m ñn{e©H$m)
CQ = CR (dVw©imbm C ‘YyZ H$mT>boë¶m ñn{e©H$m)
ABC Mr n[a{‘Vr = AP + BQ + BQ + CR + CR + AP
= 2AP + 2BQ + 2CR = 2(AP + BQ + CR)
ñdmܶm¶ 10.4
A. ñn{e©Ho$À¶m JwUY‘m©da AmYm[aV g§»¶mË‘H$ g‘ñ¶m gmoS>dm.
1. AmH¥$Vr‘ܶo PQ, PR Am{U BC øm dVw©imÀ¶m ñn{e©H$m AmhoV. BCñn{e©H$m dVw©imbm 'X' ‘ܶo ñne© H$aVo. Oa PQ = 7 g|.‘r. VaPBC Mr n[a{‘Vr H$mT>m.
2. 13 g|.‘r. Am{U 5 g|.‘r. {ÌÁ¶oMr XmoZ g‘H|$Ðr¶ dVw©io H$mT>m.AmVrb dVw©imbm ñne© H$aUmè¶m ~mhoarb dVw©imÀ¶m OrdoMr bm§~rH$mT>m.
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3. ABC ‘ܶo AB = 12 g|.‘r., BC = 8 g|.‘r. Am{U AC = 10 g|.‘r.Va AF, BD Am{U CE H$mT>m.
4. ABCD Mm ¡H$moZm‘ܶo BC = 38 g|.‘r., QB = 27 g|.‘r.DC = 25 g|.‘r. Am{U AD DC Va dVw©imMr {ÌÁ¶m H$mT>m.
5. {Xboë¶m AmH¥$Vr‘ܶo AB = BC, ABC = 680. O ‘ܶoAgboë¶m dVw©imÀ¶m DA Am{U DB ¶m ñn{e©H$m AmhoV. Va(i) ACB (ii) AOB Am{U (iii) ADB Mr ‘mno H$mT>m.
B. ñn{e©H$m§À¶m JwUY‘m©da AmYm[aV Cnà‘o¶
1. ABCD Mm¡H$moZmV dVw©i Am§Va{bIrV Ho$bobo Amho Va {gÕ H$am H$sAB + CD = AD + BC.
2. 'O' ‘ܶ Agboë¶m dVw©imbm AP Am{U AQ øm ñn{e©H$m A ¶m ~møq~XþVyZ H$mT>boë¶m AmhoV. Va {gÕH$am H$s PAQ = 2. OPQ.
3. AmH¥$Vr‘ܶo XmoZ dVw©io EH$‘oH$m§Zm 'P' ‘ܶo ~mø ñne©H$aVmV. øm dVw©imMr AB hr g‘mB©H$ ~mø ñn{e©H$m Amho.Va {gÕ H$am H$s(a) P ‘Yrb ñn{e©H$m AB bm Q ‘ܶo Xþ mJVo.(b) APB = 90°.
4. b§~ ñn{e©Ho$Mr EH$ OmoS>r dVw©imbm ~mø q~XþVyZ H$mT>bobr Amho Va {gÕ H$am H$s à˶oH$ ñn{e©Ho$Mr bm§~rhr dVw©imÀ¶m {ÌÁ¶oBVH$s AgVo.
5. Oa g‘m§Va wO Mm¡H$moZmÀ¶m ~mOy dVw©imbm ñne© H$aVmV Va {gÕ H$am H$s g‘m§Va^wO Mm¡H$moZ hm g‘ wOMm¡H$moZ Amho.
6. AmH¥$Vr‘ܶo Oa AB = AC Va {gÕ H$am H$s BQ = QC.
dVw©imbm ~mø q~XþVyZ ñn{e©H$m H$mT>Uo.
CXmhaU … 1.5 g|.‘r. {ÌÁ¶oMo dVw©i H$mT>m. dVw©i‘ܶmnmgyZ 2.5 g|.‘r. darb ~møq~XþVyZ XmoZ ñn{e©H$m H$mT>m.ñn{e©Ho$Mr bm§~r ‘moOm Am{U nS>VmiyZ nhm.
{Xbobo … r = 1.5 g|.‘r. d = 2.5 g|.‘r.
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A BM
A BM
Q
P
A BM
Q
P
nm¶ar 1 … AB aofmI§S> 2 g|.‘r. AgUmam (BVH$m) nm¶ar 2 … AB Mm b§~ Xþ^mOH$ H$mT>m Am{UAB Mm ‘ܶq~Xÿ M Aer IwU H$am.H$mT>m. A ‘ܶ ‘mZyZ 1.5 g|.‘r. {ÌÁ¶oMo dVw©i H$mT>m.
A B
nm¶ar 3 … MA qH$dm MB {ÌÁ¶oMo AJmoXa H$mT>boë¶m
dVw©imbm N>oXUmao dVw©i H$mT>m Am{U N>oXZ q~XÿÀ¶m
IwUm H$ê$Z P Am{U Q hr Zm§d o{bhm.
nm¶ar 4 … BP Am{U BQ gm§Ym. BP Am{U BQ ømAno{jV ñn{e©H$m AmhoV.
nm¶ar 5 …‘moO‘mnmZo ñn{e©Ho$Mr bm§~r BP = BQ =2g|.‘r. {heo~mZo nS>VmiUo.
t = 2 2d r = 2 22 5 6 25(( 1 25 25)) = 4 = 2 g|.‘r.
ñdmܶm¶ 10.5
1. 6 g|.‘r. {ÌÁ¶oMo dVw©i H$mT>m Am{U dVw©i‘ܶmnmgyZ 10 g|.‘r. darb ~mø q~XþVyZ ñn{e©H$m H$mT>m.ñn{e©Ho$Mr bm§~r ‘moOm Am{U nS>Vmim.
2. 3.5 g|.‘r. {ÌÁ¶oÀ¶m dVw©imbm dVw©imnmgyZ (narKmnmgyZ) 3.5 g|.‘r. darb q~XþVyZ XmoZ ñn{e©H$m H$mT>m. 3. 5.5 g|.‘r. {ÌÁ¶oÀ¶m dVw©imbm dVw©imnmgyZ 3.5 g|.‘r. darb q~XþVyZ EH$ ñn{e©H$m H$mT>m.
4. 5 g|.‘r. bm§~rMr b§~ AgUmar ñn{e©Ho$Mr EH$ OmoS>r dVw©imbm H$mT>m.5. 2 g|.‘r. Am{U 4 g|.‘r. {ÌÁ¶o§À¶m XmoZ g‘H|$Ðr¶ dVw©imZm dVw©i‘ܶmnmgyZ 8 g|.‘r. A§Vamdarb q~XþVyZ
ñn{e©H$m H$mT>m.
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Circle-Tangent Properties 247
ñne© dVw©io … Imbr {Xboë¶m dVw©im§À¶m OmoS>rMo {ZarjU H$am.
AmH¥$Vr 1 AmH¥$Vr 2 AmH¥$Vr 3
A B C D E FP
A
B
AmH¥$Vr 1 ‘ܶo A Am{U B ‘ܶ AgUmar XmoZ dVw©io EH$‘oH$mnmgyZ Xÿada AmhoV. ˶m§Zm H$moUVohr g‘mB©H$q~Xÿ ZmhrV.
AmH¥$Vr 2 ‘ܶo C Am{U D ‘ܶ AgUmar XmoZ dVw©io A Am{U B ‘ܶo N>oXVmV. ˶m§Zm A Am{U B ho XmoZg‘mB©H$ q~Xÿ AmhoV.
AmH¥$Vr 3 ‘ܶo E Am{U F ‘ܶ AgUmè¶m XmoZ dVw©imMm g‘mB©H$ q~Xÿ P Amho. ˶mZm ñne© dVw©io AgoåhUVmV.ñne© dVw©io … XmoZ dVw©imZm ’$º$ EH$ g‘mB©H$ ñne©q~Xÿ Agob Va ˶m§Zm ñne© dVw©io Ago åhUVmV.
AmH¥$Vr 4 AmH¥$Vr 5 AmH¥$Vr 6
O O1 OC2
C1
PA BC2
C1
AmH¥$Vr 4 ‘ܶo O Am{U O1 ‘ܶ AgUmè¶m XmoZ dVw©imZm g‘mB©H$ q~Xÿ Zmhr. ˶m§Zm doJdoJio dVw©i‘ܶ AmhoV.
AmH¥$Vr 5 ‘ܶo C1 Am{U C2 ¶m XmoZ dVw©im§Zm g‘mB©H$ dVw©i H|$Ð Amho nU ˶mZm dVw©imda g‘mB©H$ q~Xÿ
Zmhr. Aem dVw©imZm g‘H|$Ðr¶ dVw©io Ago åhUVmV.
AmH¥$Vr 6 ‘ܶo A Am{U B ‘ܶ AgUmè¶m C1 Am{U C2 ¶m dVw©imZm g‘mB©H$ q~Xÿ Amho. hr gwÕm ñne© dVw©io AmhoV.
ñne© dVw©io … XmoZ dVw©imZm g‘mB©H$ ñne©q~Xÿ Agob Va ˶mZm ñne© dVw©io Ago åhUVmV.
g‘mB©H$ ñne© [~§Xÿ AgUmao EH$ dVw©i Xþgè¶m dVw©imÀ¶m ~mhoa Agob Va ˶m dVw©imZm ~mø ñne© H$aUmar
dVw©io Ago åhUVmV. (qH$dm) Oa ñne© dVw©im§Mo ‘ܶ ñne©q~XÿÀ¶m XmoÝhr ~mOyg AgVrb Va ˶mZm ~møñne©
H$aUmar dVw©io åhUVmV.
g‘mB©H$ ñne© q~Xÿ AgUmao EH$ dVw©i Xþgè¶m dVw©imÀ¶m AmV Agob Va ˶m dVw©imZm Am§Vañne© H$aUmar
dVw©io åhUVmV. (qH$dm) Oa ñne© dVw©im§Mo ‘ܶ ñn{e©q~XÿÀ¶m EH$mM ~mOyg AgVrb Va ˶m§§Zm Am§Vañne©
H$aUmar dVw©io åhUVmV.
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~mø ñne© dVw©io Am§Vañne© dVw©io
AmH¥$Vr 1 AmH¥$Vr 2
ñne© H$aUmè¶m dVw©im§À¶m dVw©i‘ܶmVrb A§Va Am{U ˶m§À¶m {ÌÁ¶m ¶m‘Yrb g§~§Y …H¥$Vr 1 : Imbrb AmH¥$VtMo {ZarjU H$am, ‘moOm Am{U Imbr {Xboë¶m gmaUr‘ܶo ‘m{hVr Z‘yX H$am.
A BP A BP
AmH¥$VrAP(R) BP(r) AB(d)AP, BP Am{U AB ¶m‘Yrb
g§~§Y åhUOo R, r Am{U d
1
2
darb {ZarjUmdê$Z Vwåhr Agm {ZîH$f© H$mT>mb H$s(i) Oa XmoZ dVw©io EH$‘oH$m§Zm ~mø ñne© H$aV AgVrb Va ˶m§À¶m dVw©i‘ܶmVrb A§Va ho {ÌÁ¶oÀ¶m
~oaOoBVHo$ AgVo. [d = R + r](ii) Oa XmoZ dVw©io EH$‘oH$m§Zm Am§Vañne© H$aV AgVrb Va ˶m§À¶m dVw©i‘ܶmVrb A§Va ho {ÌÁ¶oÀ¶m
dOm~mH$s BVHo$ AgVo. [d = R – r]H¥$Vr 2 … dVw©i‘ܶmVrb A§Va 8 g|.‘r. AgUmar 5 g|.‘r. Am{U 3 g|.‘r. {ÌÁ¶|Mr XmoZ dVw©io H$mT>m.
{ÌÁ¶|Mr ~oarO Am{U dVw©i‘ܶmVrb A§Va ¶m‘ܶo Vwåhmbm H$moUVm g§~§Y AmT>iVmo.H¥$Vr 3 … dVw©i‘ܶmVrb A§Va 2 g|.‘r. AgUmar 5 g|.‘r. Am{U 3 g|.‘r {ÌÁ¶|Mr XmoZ dVw©io H$mT>m.
{ÌÁ¶|Mr dOm~mH$s Am{U dVw©i‘ܶmVrb A§Va ¶m‘ܶo Vwåhmbm H$moUVm g§~§Y AmT>iVmo?
ñne© H$aUmè¶m dVw©im§Mo dVw©i‘ܶ Am{U ñne© q~Xÿer g§~§{YV JwUY‘© …
A BP A BP
A BP A B P
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Circle-Tangent Properties 249
darb ñne© H$aUmè¶m dVw©imÀ¶m g§X^m©dê$Z,
1. Zm§do qbhm (a) ñne© q~Xÿ (b) ˶m§Mo dVw©i‘ܶ
2. AmH¥$Vr 1 ‘Yrb APB Am{U AmH¥$Vr 2 ‘Yrb ABP H$moU˶m àH$maMm H$moZ Amho?
3. AmH¥$Vr 1 ‘Yrb A, P, B Am{U AmH¥$Vr 2 ‘Yrb A, B, P ho q~Xÿ H$go AmhoV? H$m?
darb H¥$Vrdê$Z Amåhr Agm {ZîH$f© H$mT>Vmo H$s,
Oa XmoZ dVw©io EH$‘oH$m§Zm ñne© H$aV AgVrb Va ˶m§Mo dVw©i‘ܶ Am{U ñne© q~Xÿ EH$aofr¶ AgVmV.
AmVm AmnU Vm{H©$H$ÑîQ>çm à‘o¶ {gÕ H$ê$.
à‘o¶ … Oa XmoZ dVw©io EH$‘oH$m§Zm ñne© H$aV AgVrb Va ˶m§Mo dVw©i‘ܶ Am{Uñne© q~Xÿ EH$aofr¶ AgVmV.
KQ>Zm 1 … Oa XmoZ dVw©io EH$‘oH$m§Zm ~møñne© H$aV AgVrb Va ˶m§Mo dVw©i‘ܶAm{U ñne© q~Xÿ EH$aofr¶ AgVmV.
J¥hrV … ñne© H$aUmè¶m dVw©im§Mo A Am{U B ho dVw©i‘ܶ AmhoV.P hm ñne©q~Xÿ Amho.
gmܶ … A, P Am{U B ho EH$aofr¶ AmhoV.
aMZm … XPY ñn{e©H$m H$mT>m.
{gÕVm : {dYmZ H$maU
AmH¥$Vr‘ܶo
APX = 90° .....(1) ñne© q~XþVyZ H$mT>bobr {ÌÁ¶m ñn{e©Ho$bm b§~ AgVo.
BPX = 90° .....(2)
APX + BPX = 90° + 90° (1) Am{U (2) {‘i{dë¶mZo
APB = 180° APB hm gaiH$moZ Amho.
APB hr gaiaofm Amho.
A, P Am{U B ho EH$aofr¶ AmhoV.
KQ>Zm 2 … Oa XmoZ dVw©io EH$‘oH$m§Zm Am§Vañne© H$aV AgVrb Va ˶m§Mo dVw©i‘ܶ Am{Uñne©q~Xÿ EH$aofr¶ AgVmV.
J¥hrV … A Am{U B ho ñne© dVw©imMo dVw©iH|$Ð AmhoV P hm ñne©q~XÿAmho.
gmܶ … A, B Am{U P ho EH$aofr¶ AmhoV.
aMZm … XPY ñn{e©H$m H$mT>m. AP Am{U BP gm§Ym.
{gÕVm …
AmH¥$Vr‘ܶo
X
Y
A BP
X
Y
A B P
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APX = 90°..... (1) ñne© q~XþVyZ H$mT>bobr {ÌÁ¶m ñn{e©Ho$bm b§~ AgVo.
BPX = 90° ..... (2) ñne© q~XþVyZ H$mT>bobr {ÌÁ¶m ñn{e©Ho$bm b§~ AgVo.
APX = BPX = 90°
AP Am{U BP ho EH$mM aofoda AmhoV. A, B Am{U P ho EH$aofr¶ AmhoV.
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1 … VrZ dVw©io EH$‘oH$m§Zm ~møñne© H$aVmV. Oa dVw©imMo dVw©i‘ܶgm§YyZ ~Zboë¶m {ÌH$moUmÀ¶m ~mOy AZwH«$‘o 10 g|.‘r., 14 g|.‘r. Am{U 16g|.‘r. AmhoV Va à˶oH$ dVw©imMr {ÌÁ¶m H$mT>m.
CH$b … A, B Am{U C ‘ܶ AgUmar dVw©io AZwH«$‘o P, Q Am{U R ‘ܶoAmH¥$VrV Xe©{dë¶mà‘mUo EH$‘oH$m§Zm ~møñne© H$aVmV.
g‘Om AP = x PB = BQ = 10 – x
RC = CQ = 14 – x
na§Vw, CQ + BQ = 16
14 – x + 10 – x = 16
24 – 2x = 16
24 – 16 = 2x
2x = 8
x =8
2 = 4
CXmhaU 2 … AmH¥$Vr‘ܶo 9 g|.‘r. Am{U 2 g|.‘r. {ÌÁ¶oÀ¶m dVw©im§Mo AZwH«$‘o P Am{U Q ho dVw©i‘ܶ AmhoV.Oa PRQ = 90° Am{U PQ = 17 g|.‘r. Va R ‘ܶ AgUmè¶m dVw©imMr {ÌÁ¶m H$mT>m.
CH$b … R ‘ܶ AgUmè¶m dVw©imMr {ÌÁ¶m = x EH$H$ ‘mZy.
PQR ‘ܶo PQ = 17 g|.‘r.
PR = (x + 9) g|.‘r.
QR = (x + 2) g|.‘r. Am{U PRQ = 90°
PQ2 = PR2 + QR2 (nm¶W°Jmoag à‘o¶) 172 = (x + 9)2 + (x + 2)2
289 = x2 + 81 + 18x + x2 + 4 + 4x2x2 – 22x + 85 – 289 = 0
2x2 + 22x – 204 = 0 2
AR = AP = 4 g|.‘r A ‘ܶ Agboë¶m dVw©imMr {ÌÁ¶m
BQ = 10 – 4 = 6 g|.‘r B ‘ܶ Agboë¶mdVw©imMr {ÌÁ¶m
CR = 14 – 4 = 10 g|.‘r C ‘ܶ Agboë¶m dVw©imMr {ÌÁ¶m
PQ
R x x
2 9
A
B
C
xy
z
x
yz
P
Q
R
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Circle-Tangent Properties 251
x2 + 11x – 102 = 0 (x + 17)(x – 6) = 0
x + 17 = 0 qH$dm x – 6 = 0
x = –17 qH$dm x = 6
R ‘ܶ AgUmè¶m dVw©imMr {ÌÁ¶m = 6 g|.‘r.
CXmhaU 3 … A Am{U B ‘ܶ AgUmar dVw©io EH$‘oH$m§Zm Am§Vañne© H$aVmV.P hm ñne© q~Xÿ Amho. Va {gÕ H$am H$s, AR || BQ.
CH$b … BPQ = xº ‘mZm.
PBQ ‘ܶo
BP = BQ (EH$mM dVw©imÀ¶m {ÌÁ¶m)
BQP = BPQ (g‘mZ ~mOy g‘moarb H$moZ)
BQP = x° ......(1) ( BPQ = x°)
˶mMà‘mUo PAR ‘ܶo
AP = AR (EH$mM dVw©imÀ¶m {ÌÁ¶m)
ARP = APR (g‘mZ ~mOy g‘moarb H$moZ)
ARP = xº ......(2) ( APR = x°
(1) d (2) H$ê$Z
BQP = ARP (gma»¶mM H$moZmer g‘mZ AgUmao H$moZg‘mZ AgVmV.
g§JV H$moZ g‘mZ AmhoV.
AR || BQ åhUyZ {gÕ Pmbo.
ñdmܶm¶ 10.6
A. ñne© dVw©imdarb g§»¶mË‘H$ CXmhaUo …
1. VrZ dVw©io EH$‘oH$m§Zm ~møñne© H$aVmV. Va dVw©imMo dVw©i‘ܶ gm§YyZ ~Zboë¶m {ÌH$moUmÀ¶m ~mOy AZwH«$‘o7 g|.‘r., 8 g|.‘r. Am{U 9 g|.‘r. AmhoV Va à˶oH$ dVw©imMr {ÌÁ¶m H$mT>m.
2. AmH¥$Vr‘ܶo A, B Am{U C ‘ܶ AgUmar VrZ dVw©io AmH¥$VrV Xe©{dë¶mà‘mUoñne© H$aVmV. Oa øm dVw©imMr {ÌÁ¶m AZwH«$‘o 8 g|.‘r., 3 g|.‘r. Am{U 2g|.‘r. Amho Va ABC Mr n[a{‘Vr H$mT>m.
3. AmH¥$Vr‘ܶo AB = 10 g|.‘r., AC = 6 g|.‘r. Am{U bhmZ dVw©imMr {ÌÁ¶m 'X'g|.‘r. Amho Va 'X' H$mT>m.
A B P
RQ
A B
P Q
CO
x
AB
C
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252 UNIT-10
A
P Q
C
Ox
M D B
R
2
A
B
P
C1
C2
B. ñne© dVw©imda AmYmarV Cnà‘o¶ …
1. A Am{U B ‘ܶ Agboë¶m XmoZ dVw©im§À¶m ñne© q~XþVyZ H$mT>bobr gaiaofm dVw©im§Zm AZwH«$‘o P Am{U Q‘ܶo N>oXVo. AP Am{U BQ ho g‘m§Va AmhoV Ago XmIdm.
2. X Am{U Y ‘ܶ AgUmar XmoZ dVw©io EH$‘oH$m§Zm P ‘ܶo ~møñne© H$aVmV. à˶oH$ dVw©im‘ܶo EH$ ¶mà‘mUoH$mT>bobo AB Am{U CD ho ì¶mg nañnam§Zm g‘m§Va AmhoV Va {gÕ H$am H$s B, P Am{U C ho EH$aofr¶AmhoV.
3. 'O' ‘ܶ Agboë¶m dVw©imV ì¶mg AB Am{U Ordm AD H$mT>bobr Amho. OA ì¶mg AgUmao AD bm
C ‘ܶo N>oXUmao Xþgao EH$ dVw©i H$mT>bobo Amho. Va {gÕ H$am H$s BD = 2OC .
4. {Xboë¶m AmH¥$Vr‘ܶo AB = 8 g|.‘r. M hm AB Mm ‘ܶq~Xÿ Amho.
AB da AY©dVw©io H$mT>bobr AmhoV. AM Am{U MB ho ì¶mg AmhoV.'O' ‘ܶ AgUmao dVw©i gd© {VÝhr AY© dVw©im§Zm AmH¥$VrV Xe©{dë¶mà‘mUo
ñne© H$aVo. Va øm dVw©imMr {ÌÁ¶m16 AB Amho Ago {gÕ H$am.
ñne© dVw©im§Mr aMZm
CXmhaU 1 … 2 g|.‘r. Am{U 1 g|.‘r. {ÌÁ¶|Mr Am§Vañne© H$aUmar XmoZdVw©io H$mT>m Am{U ñne© q~XÿMr IwU H$am.
{Xbobo ..… C1 = R = 2 g|.‘r., C2 = r = 1 g|.‘r.
nm¶ar 1 … 'd' H$mT>md = R – r = 2 – 1 = 1 g|.‘r.
nm¶ar 2 … AB = 1 g|.‘r. H$mT>m. A ‘ܶ AgUmao 2 g|.‘r.BV³¶m {ÌÁ¶oMo dVw©i H$mT>m.
nm¶ar 3 … 1 g|.‘r. BV³¶m {ÌÁ¶oMo B ‘ܶ AgUmao dVw©i H$mT>m.
nm¶ar 4 … AB nwT>o dmT>{dë¶mg ñne© q~Xÿ P ‘ܶo {‘iVo.
ñdmܶm¶ 10.7
1. 5 g|.‘r. Am{U 2 g|.‘r. {ÌÁ¶oMr ~mø ñne© H$aUmar XmoZ dVw©io H$mT>m.
2. dVw©i‘ܶmVrb A§Va 7 g|.‘r. AgUmar 4.5 g|.‘r. Am{U 2.5 g|.‘r. {ÌÁ¶|Mr XmoZ dVw©io H$mT>m.
3. 4 g|.‘r. Am{U 2.5 g|.‘r. {ÌÁ¶|Mr Am§Vañne© H$aUmar XmoZ dVw©io H$mT>m. ˶m§À¶m dVw©i‘ܶmVrb A§Va‘moOm Am{U nS>Vmim.
4. Am§Vañne© H$aUmè¶m XmoZ dVw©im§À¶m dVw©i‘ܶmVrb A§Va 2 g|.‘r. Amho. Oa EH$m dVw©imMr {ÌÁ¶m 4.8g|.‘r. Agob Va Xþgè¶m dVw©imMr {ÌÁ¶m H$mT>m. Am{U ñne© H$aUmar dVw©io H$mT>m.
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Circle-Tangent Properties 253
g‘mB©H$ ñn{e©H$m
Imbrb CXmhaUm§Mm Aä¶mg H$am.
CXmhaU 1 … gm¶H$brÀ¶m MmH$mH$S>o nhm Or dVw©io Xe©{dVmV, añ˶mdê$Z{’$aUmao MmH$ aofm Xe©{dVo. XmoÝhr MmH$mZm aofm ñne© H$aVo.
CXmhaU 2 … Imbrb AmH¥$VtMo {ZarjU H$am à˶oH$ KQ>ZoV EH$mM gaiaofobmñne© H$aUmar XmoZ dVw©io AmhoV. gaiaofm hr XmoÝhr dVw©im§Mr ñn{e©H$mAmho. Aem ñn{e©Ho$bm g‘mB©H$ ñn{e©H$m Ago åhUVmV.
g‘mB©H$ ñn{e©H|$À¶m g§X^m©dê$Z dVw©im§À¶m pñWVrMo {ZarjU H$am.Vwåhmbm Ago {XgyZ ¶oVo H$s XmoÝhr dVw©io ñn{e©Ho$À¶m EH$mM ~mOyg AmhoV.
Oa XmoÝhr dVw©io g‘mB©H$ ñn{e©Ho$À¶m EH$mM ~mOyg (A§Jmg) AgVrb Va ˶m g‘mB©H$ ñn{e©Ho$bm g‘mB©H$~møñn{e©H$m Ago åhUVmV. (Direct Common Tangent)
CXmhaU 3 … Imbrb AmH¥$VtMo {ZarjU H$am. à˶oH$ KQ>ZoV gaiaofm hr g‘mB©H$ ñn{e©H$m Amho nU dVw©im§À¶mpñWVrMo {ZarjU H$am. dVw©io hr g‘mB©H$ ñn{e©Ho$À¶m XmoÝhr ~mOyg AmhoV.
Oa XmoÝhr dVw©io g‘mB©H$ ñn{e©Ho$À¶m XmoÝhr ~mOyg (A§Jmg) AgVrb Va ˶m g‘mB©H$ ñn{e©Ho$bm g‘mB©H$Am§Vañn{e©H$m Ago åhUVmV. (Tranverse Common Tangent)
H¥$Vr … AmH¥$VtMo {ZarjU H$am à˶oH$ KQ>Ho$Vrb àH$ma Am{U g‘mB©H$ ñn{e©Ho$Mr g§»¶m AmoiIm.
XmoZ EH$ê$n dVw©imZm g‘mB©H$ ~mø ñn{e©H$m H$mT>Uo.
1. dVw©i‘ܶmVrb A§Va 8 g|.‘r. AgUmè¶m 3 g|.‘r. {ÌÁ¶|À¶m XmoZ dVw©imbm g‘mB©H$ ~mø ñn{e©H$m H$mT>m.{Xbobo … r = 3 g|.‘r. = C1 = C2, d = 8 g|.‘r.
A
B
C
D
G HE
F
A B EF
CD
G
H
Sun Earth
Umbra
Penumbra
E
B
A
D
A B
DEC
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nm¶ar 1 … AB = 8 g|.‘r. H$mT>m. A Am{U B ‘ܶ AgUmar 3 g|.‘r. {ÌÁ¶|Mr XmoZ dVw©io H$mT>m.
A B
C1 C2
nm¶ar 2 … A Am{U B ‘YyZ XmoZ b§~ ì¶mg H$mT>m. q~XÿZm P, Q, R Am{U S hr Zm§do {bhm.
A B
P Q
R Snm¶ar 3 … PQ Am{U RS OmoS>m. PQ Am{U RS øm Amdí¶H$ (Ano{jV) g‘mB©H$ ~mø ñn{e©H$m AmhoV.
A B
P Q
R S
Q>rn … i) g‘mB©H$ ~møñn{e©H$m H$mT>ʶmMr nÕV hr EH$ê$n Agboë¶m§gmR>r g‘mZ AgVo.
a) Z N>oXUmar dVw©io (d>R+r) b) ~mø ñne© H$aUmar dVw©io (d=R+r) Am{U
c) N>oXUmar dVw©io (d<R+r)
ii) XmoZ EH$ê$n dVw©imZm H$mT>boë¶m g‘mB©H$ ~møñn{e©H$m dVw©i‘ܶ gm§YUmè¶m aofoer g‘mZAm{U g‘m§Va AgVmV.
XmoZ EH$ê$n Zgboë¶m dVw©im§Zm g‘mB©H$ ~mø ñn{e©H$m H$mT>Uo …
CXmhaU 1 … 5 g|.‘r. Am{U 2 g|.‘r. {ÌÁ¶|À¶m XmoZ dVw©i‘ܶmVrb A§Va 10 g|.‘r. Amho Va dVw©im§Zm g‘mB©H$
~mø ñn{e©H$m H$mT>m. g‘mB©H$ ~mø ñn{e©Ho$Mr bm§~r ‘moOm Am{U nS>Vmim.
{Xbobo … d = 10, C1 = R = 5 g|.‘r., C2 = r = 2 g|.‘r., C3 = R – r = 5 – 2 = 3 g|.‘r.
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Circle-Tangent Properties 255
nm¶ar 1 … AB = 10 g|.‘r. H$mT>m. A Am{U B‘ܶ AgUmar AZwH«$‘o 5 g|.‘r. Am{U 2 g|.‘r.{ÌÁ¶|Mr C1 Am{U C2 dVw©io H$mT>m.
AB
C1
C2
nm¶ar 3 … AB bm M ‘ܶo N>oXUmam b§~ Xþ mOH$H$mT>m. M ‘ܶ AgUmao MA {ÌÁ¶oMo C3 bmP Am{U Q ‘ܶo N>oXUmao C4 dVw©i H$mT>m.
AB
C1
C2C3
M
C4
Q
P
nm¶ar 5 … PB ñn{e©H$m H$mT>m.
AB
C1
C2C3
M
C4
Q
P
S
Q>rn … ˶mMà‘mUo C1 Am{U C2bm Xþgar g‘mB©H$ ~møñn{e©H$m H$mT>Vm ¶oVo.
nm¶ar 7 … ‘moO‘mnmZo ST = 9.5 g|.‘r.
{heo~mZo DCT (g‘mB©H$ ~møñn{e©H$m)
= 2 2d (R r) = 2 210 (5 2) = 100 9 = 91 = 9.5 g|.‘r.
XmoZ dVw©im§Zm g‘mB©H$ Am§Vañn{e©H$m H$mT>Uo
CXmhaU 1 … 4 g|.‘r. Am{U 2 g|.‘r. {ÌÁ¶oÀ¶m XmoZ dVw©i‘ܶmVrb A§Va 10 g|.‘r. Amho. ˶m§Zm g‘mB©H$Am§Vañn{e©H$m H$mT>m. g‘mB©H$ Am§Va ñn{e©Ho$Mr bm§~r ‘moOm Am{U nS>Vmim.
{Xbobo , d = 10 g|.‘r., C1 = R = 4 g|.‘r., C2 = r = 2 g|.‘r., C3 = R + r = 4 + 2= 6 g|.‘r.
nm¶ar 2 … A ‘ܶ AgUmao 3 g|.‘r. {ÌÁ¶oMoC3 dVw©i H$mT>m.
A B
C1C2
C3
nm¶ar 4 … AP OmoS>m Am{U Vo nwT>o dmT>{dë¶mg C1
bm S ‘ܶo N>oXVo.
AB
C1
C2C3
M
C4
Q
P
S
nm¶ar 6 … S ‘ܶ gmXmaU BP {ÌÁ¶oMm H§$g H$mT>bmAgVm C2bm T ‘ܶoo N>oXVmoo.ST Am{U BT gm§§Ym.
AB
C1
C2C3
M
C4
Q
P
S
T
Q>rn … aMZoMr V§VmoV§VnUm VnmgʶmgmR>rPBTS hm Am¶V Agbm nm{hOo.
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256 UNIT-10
nm¶ar 1 … AB = 10 g|.‘r. A Am{U B ‘ܶ AgUmarAZwH«$‘o 4 g|.‘r. Am{U 2 g|.‘r. {ÌÁ¶oMr dVw©io H$mT>m.dVw©imZm C1 Am{U C2 Zm§do Úm.
nm¶ar 3 … AB bm M ‘ܶo N>oXUmam b§~ Xþ mOH$ H$mT>m.M ‘ܶ AgUmao MA {ÌÁ¶oMo C3 bm P Am{U Q ‘ܶoN>oXUmao C4 dVw©i H$mT>m.
nm¶ar 5 … PB ñn{e©H$m H$mT>m.
nm¶ar 7 … ‘moO‘mnmZo ST = 8 g|.‘r.2 2d (R r) = 2 210 (4 2) = 100 36 = 64 = 8 g|.‘r.
A B
C1C2
nm¶ar 2 … A ‘ܶ AgUmao 3 g|.‘r. {ÌÁ¶oMo C3
dVw©i H$mT>m.
AB
C1
C2C3
nm¶ar 4 … AP gm§Ybo Agbm C1 bm S ‘ܶo N>oXVo.
A B
C3
C2
C1
M
C4P
Q
S A B
C3
C2
C1
M
C4P
Q
A B
C3
C2
C1
M
C4P
Q
S
Q>rn … ˶mMà‘mUo C1
Am{U C2 bm Xþgar g‘mB©H$Am§Va ñn{e©H$m H$mT>Vm ¶oVo.
nm¶ar 6 … S ‘ܶ ‘mZyZ PB {ÌÁ¶oZo H§$g H$mT>bm AgVmC2 bm T ‘ܶo N>oXVmo. ST gm§Ym.
A B
C3
C2
C1
M
C4P
Q
S
T
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Circle-Tangent Properties 257
Q>rn … i) g‘mB©H$ ~møñn{e©H$m H$mT>ʶmMr nÕV hr EH$ê$n Agboë¶m§gmR>r g‘mZ AgVo.
a) Z N>oXUmar dVw©io (d>R+r) (b) ~mø ñne© H$aUmar dVw©io (d=R+r) Am{U (c) N>oXUmar dVw©io
(d<R+r)
ii) dVw©imZm Am§Vañn{e©H$m (TCT) H$mT>ʶmMr nÕV hr EH$ê$n Agboë¶m Am{U EH$ê$n Zgboë¶m Z
N>oXUmè¶m dVw©im§gmR>r (d>R+r) g‘mZ AgVo.
ñdmܶm¶ 10.8
I. (A). 1. 3 g|.‘r. {ÌÁ¶|À¶m XmoZ EH$ê$n dVw©i‘ܶmVrb A§Va 10 g|.‘r. Amho. g‘mB©H$ ~møñn{e©H$m
H$mT>m.
2. 3.5 g|.‘r. {ÌÁ¶|Mr XmoZ EH$ê$n dVw©io H$mT>m Am{U ˶m‘Yrb A§Va 3 g|.‘r. Amho. dVw©imZm XmoZ
g‘mB©H$ ~møñn{e©H$m H$mT>m.
3. 4.5 g|.‘r. {ÌÁ¶|À¶m ~møñne© H$aUmè¶m XmoZ dVw©imZm g‘mB©H$ ~møñn{e©H$m H$mT>m.
4. 2.5 g|.‘r. {ÌÁ¶|À¶m XmoZ dVw©i‘ܶmVrb A§Va 4 g|.‘r. Amho. dVw©im§Zm g‘mB©H$ ~mø ñn{e©Ho$Mr
EH$ OmoS>r H$mT>m.
(B). 1. 5 g|.‘r. Am{U 2 g|.‘r. {ÌÁ¶|À¶m XmoZ dVw©i‘ܶmVrb A§Va 3 g|.‘r. Amho g‘mB©H$ ~møñn{e©H$m H$mT>m.
2. Am§Vañne© H$aUmè¶m 4.5 g|.‘r. Am{U 2.5 g|.‘r. {ÌÁ¶|À¶m XmoZ dVw©imZm g‘mB©H$ ~møñn{e©H$m H$mT>m.
3. 4 g|.‘r. Am{U 2 g|.‘r. {ÌÁ¶|À¶m XmoZ dVw©i‘ܶmVrb A§Va 8 g|.‘r. Amho. dVw©imZm g‘mB©H$
~møñn{e©H$m H$mT>m. ñn{e©Ho$Mr bm§~r ‘moOm Am{U nS>Vmim.
4. 5.5 g|.‘r. Am{U 3.5 g|.‘r. {ÌÁ¶|Mr XmoZ dVw©io EH$‘oH$m§Zm ~mø ñne© H$aVmV. g‘mB©H$
~møñn{e©H$m H$mT>m Am{U ˶m§Mr bm§~r ‘moOm.
5. 5 g|.‘r. Am{U 3 g|.‘r. {ÌÁ¶|À¶m XmoZ dVw©i‘ܶmVrb A§Va 5 g|.‘r. Amho. dVw©imZm XmoZ
g‘mB©H$ ~møñn{e©H$m H$mT>m.
6. 6 g|.‘r. Am{U 3 g|.‘r. {ÌÁ¶|Mr XmoZ dVw©io 1 g|.‘r. A§Vamda AmhoV. g‘mB©H$ ~møñn{e©H$m
H$mT>m. ˶m§Mr bm§~r ‘moOm Am{U nS>Vmim.
II.(A). 1. 6 g|.‘r. Am[¨U 2 g|.‘r. {ÌÁ¶|À¶m XmoZ dVw©i‘ܶmVrb A§Va 8 g|.‘r. Amho. dVw©imZm g‘mB©H$
Am§Vañn{e©H$m H$mT>m.
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258 UNIT-10
2. 4.5 g|.‘r. Am[U 2.5 g|.‘r. {ÌÁ¶|Mr XmoZ dVw©io EH$‘oH$m§Zm ~møñne© H$aVmV. dVw©im§Zm g‘mB©H$
Am§Vañn{e©H$m H$mT>m.
3. à˶oH$s 3 g|.‘r. {ÌÁ¶oÀ¶m XmoZ dVw©i‘ܶmVrb A§Va 6 g|.‘r. Amho. dVw©imZm g‘mB©H$ Am§Vañn{e©H$m H$mT>m.
(B). 1. 2.5 g|.‘r. {ÌÁ¶oÀ¶m XmoZ EH$ê$n dVw©i‘ܶmVrb A§Va 8 g|.‘r. Amho. g‘mB©H$ Am§Vañn{e©H$m
H$mT>m.
2. 3 g|.‘r. Am{U 2 g|.‘r. {ÌÁ¶|Mr XmoZ dVw©io 8 g|.‘r. A§Vamda AmhoV. g‘mB©H$ Am§Vañn{e©H$m H$mT>m
Am{U {VMr bm§~r ‘moOm.
3. 4 g|.‘r. Am[U 2 g|.‘r. {ÌÁ¶|À¶m XmoZ dVw©imZm 8 g|.‘r. bm§~rÀ¶m Am§Vañn{e©H$m H$mT>m.
4. 4 g|.‘r. Am{U 3 g|.‘r. {ÌÁ¶|À¶m XmoZ dVw©i‘ܶmVrb A§Va 10 g|.‘r. Amho. g‘mB©H$ Am§Vañn{e©H$m
H$mT>m. ‘moOm Am{U {heo~mZo nS>Vmim.
5. 2.5 g|.‘r. Am{U 3.5 g|.‘r. {ÌÁ¶|À¶m XmoZ dVw©i‘ܶmVrb A§Va 8 g|.‘r. Amho. g‘mB©H$
Am§Vañn{e©H$m H$mT>m. {VMr bm§~r ‘moOm Am{U {heo~mZo nS>Vmim.
* * * *
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Circle-Tangent Properties 259
CÎmao
ñdmܶm¶ … 10.4
A. 1. 14 g|.‘r. 2. AB = 24g|.‘r. 3. AF = 7g|.‘r. BD = 5 g|.‘r. Am{U CE = 3 g|.‘r.
4. 14 g|.‘r. 5. (i) 056ACB (ii) 0112AOB (iii) 068ADB
ñdmܶm¶ … 10.6
A. 1. 4 g|.‘r., 3 g|.‘r.Am{U 5 g|.‘r. 2. ABC Mr n[a{‘Vr = 16 g|.‘r. 3 .x = 2.4 g|.‘r.
*****
Tangent Properties
Tangent at apoint on a circle
Tangent at the endsof the diameter
Tangents at thenon-centre ends
of the radii
Tangent to a circleif angle between the
tangents is given
Tangent at the endsof the chord
PropertiesConstructions Common tangents totwo circles.
DCT TCT
To twocongruent circles
To two non-congruent circles
* Externally non-touching* Externally touching* Intersecting
Internallytouching
Externallynon-touching
Externallytouching
Tangents from anexternal point to circle Touching circles
Numerical Problems Riders
ñn{e©H$m§Mo JwUY‘©
aMZm
dVw©imdarb q~XÿVyZñn{e©H$m
{ÌÁ¶m§À¶m dVw©i‘ܶZgboë¶m Q>moH$mnmgyZ
ñn{e©H$m
ñn{e©H$m§‘Yrb H$moZ {Xbm AgVmdVw©imbm ñn{e©H$m H$mT>Uo
OrdoÀ¶m Q>moH$mnmgyZñn{e©H$m H$mT>Uo
ì¶mgmÀ¶m Q>moH$mnmgyZñn{e©H$m H$mT>Uo
XmoZ EH$ê$ndVw©imZm
JwUY‘© XmoZ dVw©imZm g‘mB©H$ ñn{e©H$m
XmoZ EH$ê$nZgboë¶m dVw©imZm ~møñne© Z
H$aUmè¶m~møñne©H$aUmè¶m
* ~møñne© Z H$aUmè¶m* ~møñne© H$aUmè¶m* N>oXUmè¶m
Am§Vañne©H$aUmè¶m
ñne© dVw©iodVw©imbm ~møq~XÿVyZH$mT>boë¶m ñn{e©H$m
Cà‘o¶g§»¶mË‘H$ g‘ñ¶m
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260 UNIT-10A
mnU
g‘m
B©H$
ñn{e
©Ho$À¶
m ‘m
{hVr
Mm
gmam
§e n
mhÿ.
{Xb
obr
gmaU
r A
ä¶mg
m.
A.
dVw©i
oA
mH¥$˶
md,
RA
m{U r
g‘m
B©H$ ~
møg
‘mB©H
$ Am§V
ag‘
mB©H$
Z§.‘Y
rb g
§~§Yñn
{e©Ho$
Mr g
§»¶m
ñn{e
©Ho$M
r g§»¶
mñn
{e©Ho$
Mr g
§»¶m
1.Z
N>oXU
mard
> R
+ r
2,2,
4dV
w©io
PQ, R
STU
, VW
2.~m
ø ñ
ne©
d =
R +
r2,
1,3
H$aU
mar d
Vw©io
PQ, R
SXY
3.N>oXU
mar d
Vw©io
d <
R +
r2,
-2
MN
, PQ
4.A
m§Vañ
ne©
d =
R –
r1,
-1
H$aU
mar d
Vw©io
EF
5.g‘
H|$Ðr¶
ZgUmar
d <
R –
r-
--
dVw©io
6.g‘
H|$Ðr¶
dVw©io
d =
0-
--
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¶m KQ>H$m‘wio Vwåhmbm ¶m§Mo gwb^rH$aU hmoVo
* g‘ê$n ~hþ wOmH¥$Vr Am{U g‘ê$n {ÌH$moUm§À¶mAWmªMo ñnï>rH$aU.
* g‘ê$n {ÌH$moU Am{U EH$ê$n {ÌH$moU ¶m‘Yrb’$aH$ AmoiIUo.
* ‘yb yV à‘mUmÀ¶m à‘o¶mMo {dYmZ Am{U {gÕVm.
* ‘y.à. à‘o¶mMm ì¶Ë¶mg Am{U Cn{gÕm§V ¶m§Mo{dYmZ Am{U {gÕVm.
* g‘ê$n {ÌH$moUmgmR>r AA g‘ê$nVoMo {dYmZ Am{U{gÕVm.
* g‘ê$n {ÌH$moUmgmR>r SSS Am{U SAS g‘ê$nVoMo{dYmZ Am{U {gÕVm.
* H$mQ> H$moZ {ÌH$moUmÀ¶m H$mQ>H$moZ {eamoq~XÿVyZ H$Um©daQ>mH$bobm b§~ ¶m g§~§{YV à‘o¶mMr {gÜXVm Am{U{dYmZ
* g‘ê$n {ÌH$moUm§À¶m joÌ’$imdarb à‘o¶m§Mo {dYmZAm{U {gÕVm.
* AZw‘m{ZH$ ¶w³Ë¶m Am{U à‘o¶mda AmYmarVCnà‘o¶m§Mr {gÕVm.
* à‘o¶mda AmYm[aV X¡Z§{XZ OrdZmVrb CXmhaUm§Mon¥W:H$aU Am{U gmoS>{dUo.
Similar Triangles
* g‘ê$n ~hþ^wOmH¥$Vr Am{U g‘ê$n{ÌH$moU
* ‘yb^yV à‘mUmMm à‘o¶
* ‘ y.à.à‘ o¶mMm ì¶Ë¶mg Am{UCn{gÕm§V
* g‘ê$n {ÌH$moUm§À¶m AA Am{U SSSH$gmoQ>r
* g‘ê$n {ÌH$moUm§À¶m AA H$gmoQ>tMr{gÕm§V.
* g‘ê$n {ÌH$moUm§À¶m joÌ’$imdarbà‘o¶
11
{‘boQ>gMm Woëg
(624-546 B.C., J«rg)
Woëg hm n{hbm ‘m{hV Agbobm
VËdkmZr Am{U J{UVVk. ^y{‘Vr‘Yrb
AZw‘m{ZH$ ¶w{º$dmX dmnaʶmMo n{hbo
lo¶ ¶m§Zm {‘iVo. ¶mZo ^y{‘Vr‘Yrb
AZoH$ {gÕm§Vm§Mm emoY bmdbm. ¶m§À¶m
‘VmZwgma B{Oá‘Yrb {na °{‘S>Mr C§Mr
gmdbrMm Cn¶moJ H$ê$Z g‘ê$n
{ÌH$moUmÀ¶m VËdmZo H$mT>Vm ¶ oVo.
The universe cannot be read until wehave learnt the language in which it iswritten. It is written in mathematicallanguage, and the letters are triangles,circles and other geometrical figures,without which it is humanly impossible tocomprehend a single word.
- Galileo Galilei
g‘ê$n {ÌH$moU
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262 UNIT-11
‘mJrb B¶ÎmoV Vwåhr {ÌH$moU Am{U ˶mÀ¶m JwUY‘m©{df¶r {eH$bm AmhmV. ¶m JwUY‘mªMm Cn¶moJ {Z˶
OrdZmVrb CXmhaUo gmoS>{dʶmg hmoVmo. ¶mn¡H$s H$mhtMm ^m¡{VH$emó, agm¶Zgmó B˶mXr {df¶m§Mm Aä¶mg
H$aʶmg hmoVmo. {ÌH$moU Am{U ˶m§À¶m JwUY‘mªMm g‘mdoe Agbobr H$m§hr CXmhaUo Imbr {Xbr AmhoV.
1. ( )( )( )A s s a s b s c
OoWo 2s = a + b + c.
{ÌH$moUm§Mo joÌ’$i H$mT>ʶmMo ho gyÌ Amho. ho gyÌ H$go V¶ma
(derived) Pmbo ho Vwåhmbm ‘m{hV Amho H$m?
2. AB = 14 g|.‘r.
Amåhmbm AB 2 : 5. JwUm oÎmamV {d^mJm¶Mo Amho.
àm¶mo{JH$[a˶m ho H$go H$aVm ¶oBb?
3. 1 1 1u v f
¶mbm Amaí¶mMo gyÌ qH$dm q^JmMo gyÌ åhUVmV, ¶m{df¶r
Vwåhr ^m¡{VH$emóm‘ܶo {eH$bm AmhmV. ho gyÌ {‘i{dVm
¶oVo ¶mMm Vwåhr H$Yr {dMma Ho$bm AmhmV H$m?
¶m gd© àým§gmR>r Am{U A{YH$ ‘m{hVrgmR>r ¶m KQ>H$mV Vwåhmbm Cnm¶ {XgyZ ¶oVrb.
Imbrb CXmhaUmMm {dMma H$am.
XmoZ JQ>mVrb {dÚmWu Imbrb àH$ën H$aVmV. EH$m JQ>mVrb
{dÚmWu PmS>mÀ¶m nS>booë¶m gmdbrMr bm§~r ‘moOVmV.
A
B C a
bc
M
N
P
A
BCF
A
B
A B14 cm
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Similar Triangles 263
˶mM doir, PmS>mÀ¶m ~mOybm Agboë¶m VrZ ‘moR>¶m C§MrÀ¶m Cä¶m Im§~mÀ¶m nS>boë¶m gmdbrMr Xþgè¶m
JQ>mVrb {dÚmWu ‘moOVmV. ¶m ‘m{hVrdê$Z ˶mZm PmS>mMr C§Mr H$mT>md¶mMr Amho. ho e³¶ Amho H$m?
^y{‘Vr‘Yrb "g‘ê$n {ÌH$ m oU' ¶m ‘hËdmÀ¶m
g§H$ënZoMm Cn¶moJ H$ê$Z PmS>mMr C§Mr H$mT>Uo e³¶ Amho.
g‘ê$n {ÌH$moU g‘OyZ KoʶmgmR>r àW‘ ^m¡{‘{VH$ AmH$ma
Am{U ‘mn ¶m{df¶rÀ¶m ‘hËdmÀ¶m H$ënZm§Mm àW‘ Aä¶mg
H$ê$.
àVbmdarb ^m¡{‘{VH$ AmH¥$˶m§Mm AmH$ma Am{U ‘mn ¶m§À¶m
g§X^m©V VrZ e³¶Vm AmhoV.
e³¶Vm -1 e³¶Vm -2 e³¶Vm-3
AmH¥$˶mZm EH$ Va g‘mZ AmH$ma AmH¥$˶mZm g‘mZ AmH$ma" g‘mZ AmH$ma Agboë¶m na§Vw
qH$dm g‘mZ ‘mn ¶mn¡H$s H$moUVohr Am{U g‘mZ ‘mn AgVo. ‘mn Zgboë¶m AmH¥$˶m.
ZgVo. Mm¡ag Am{U g‘ wO g‘mZ ‘mno AgUmao XmoZ {ÌH$moZ doJdoJir ‘mno Agbobo XmoZ
Mm¡H$moZ g‘mZ g‘H$moZ {ÌH$moU
¶mZm EH$ê$n {ÌH$moU Ago Aem AmH¥$˶mZm g‘ê$n AmH¥$˶m
åhUVmV. Ago åhUVmV.
EH$ê$nVo à‘mUoM y{‘Vr‘ܶo g‘ê$nVm g§~§Y XoIrb ‘hËdmMr ^y{‘H$m ~OmdVmo. Amnë¶m X¡Z§{XZ OrdZmV
g‘ê$nVoÀ¶m n[aH$ënZoMm ’$ma {dñVrU© à‘mUmV dmna Ho$bm Amho.
CXmhaUmW©, yJmob ‘ܶo dmnabobo Vºo$ g‘ê$nVoÀ¶m n[aH$ënZoda AmYm[aV AmhoV.
‘moR>çm B‘maVtÀ¶m ~m§YH$m‘mnydu ~Z{dboë¶m à{VH¥$Vr g‘ê$n AgVmV.
Amåhr ¶mnydu EH$ê$n {ÌH$moUm{df¶r Aä¶mg Ho$bm Amho. XmoZ {ÌH$moUm§Mm AmH$ma g‘mZ AgyZ ˶m§Mo
‘mno g‘mZ Agë¶mg Vo EH$ê$n {ÌH$moU AgVmV. AmVm AmnU Aem AmH¥$˶m§Mm A{YH$ Aä¶mg H$ê$ H$s
Á¶m§Mm AmH$ma g‘mZ Amho nU ˶m§Mo ‘mn g‘mZ AgobM Ago Zmhr. Aem AmH¥$˶mZm g‘ê$n AmH¥$˶m
åhUVmV.
OmUyZ ¿¶m!B{VhmgH$mamZr gm§{JVbo Amho H$s, gw‘mao 600BC‘ܶo J«rH$Mo à{gÕ J{UV Vk WoëgZr gmdbrÀ¶mgmhmæ¶mZo B{Oá‘Yrb {na°{‘S>Mr C§Mr emoYyZH$mT>br.
A B
CD
P Q
RS
A
B C
D
E F
P
Q R
L
M N
5 06 0
7 0
5 06 0
7 0
3 01 0 0
5 0
3 01 0 0
5 0
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264 UNIT-11
g‘ê$n AmH¥$˶m
Imbrb N>m¶m{MÌm§Mo {ZarjU H$am. Vwåhr ˶mM doir gm§Jy eH$mb H$s hr XmoÝhr N>m¶m{MÌo EH$mM
B‘maVrMr ({dYmZ gm¡Y) AmhoV. na§Vw ˶m§Mo ‘mn doJdoJio Amho. hr N>m¶m{MÌo g‘ê$n AmhoV H$m? MMm© H$am.
AmVm H$m§hr ^m¡{‘{VH$ g‘ê$n AmH¥$˶m§Mm ZrQ> {dMma H$am.
A B
A
B C
60°
60°60°
D
E F
60°
60° 60°
P Q
RS
R Q
RS
XmoZ dVw©io Zoh‘r XmoZ Mm¡ag Zoh‘r XmoZ g‘H$moZ {ÌH$moU Zoh‘rg‘ê$n AgVmV g‘ê$n AgVmV g‘ê$n AgVmV
darb CXmhaUmdê$Z Amåhr Agm {ZîH$f© H$mT>Vmo H$r
""XmoZ AmH¥$˶m g‘ê$n AgVmV Oa Am{U ’$º$ Oa ˶m§Mm AmH$ma g‘mZ AgyZ ˶m§Mr ‘mno g‘mZAgVrbM Ago Zm§hr.''
Amåhr ho {MÝh (g‘ê$n Amho Ago dmMm) AmH¥$˶m§Mr g‘ê$nVm Xe©{dʶmgmR>r dmnaVmo.
CXmhaUmW©: darb AmH¥$˶m‘Yrb {Vgè¶m g§MmMm C„oI H$am.
ABC hm DEF bm g‘ê$n Amho.
ABC DEF g‘ê$nVoMr Xþgar g§km III Amho.
‘m{hVr Amho ! g‘ê$n åhUOoM g‘mZ AmH$ma Agbobo.
Oa Amnë¶mH$S>o XmoZ AmH¥$˶m AmhoV Am{U ¶m XmoZ n¡H$s EH$ EH$Va H$‘r H$ê$Z (bhmZ H$ê$Z) qH$dmXþgar AmH$mamV ~Xb Z H$aVm dmT>{dbr (VmUbr) Va ˶m XmoZ AmH¥$˶m g‘ê$n AgVmV. {dYmZ gm¡YÀ¶mN>m¶m{MÌm‘ܶo AgoM KS>bo Am{U åhUyZ ˶m g‘ê$n AmhoV.
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Similar Triangles 265
A
B
C
DE
PQ
R
ST
AB
CD
PQ
RS
AmVmn¶ªV MMm© Ho$boë¶m gd© CXmhaUm‘ܶo Amåhr Ago J¥hrV Yabo Amho H$r {XgʶmV gd© AmH¥$˶mg‘ê$n AmhoV. na§Vw J{UVmZo AmH¥$˶m§Mr g‘ê$nVm H$er 춺$ H$ê$ eH$Vmo? Amåhmbm ¶mgmR>r g‘ê$nVoÀ¶mì¶m»¶oMr JaO Amho. Am{U ì¶m»¶oda AmYmarV H$m§hr {Z¶‘ Am{U AQ>tMm g‘mdoe ˶m AmH¥$˶m g‘ê$n AmhoVH$r ZmhrV ho R>a{dʶmg hmoVmo.
AmVm AmnU ~hþ wOmH¥$VtMr g‘ê$nVm Am{U {VÀ¶m ì¶m»¶o {df¶r Aä¶mg H$ê$.
g‘ê$n ~hþ wOmH¥$Vr (Similar polygon)
Imbrb g‘ê$n ^m¡{‘{VH$ AmH¥$˶m§À¶m OmoS>çm§Mm {dMma H$am.
à˶oH$mÀ¶m ~m~VrV g§JV H$moZ Am{U g§JV ~mOy§À¶m JwUmoÎmamMo {ZarjU H$am.
g‘ê$n ^m¡{‘{VH$ {ZarjUAmH¥$˶m§À¶m OmoS>çm
ABCD Am{U PQRS ‘ܶo
1. A P, B Q, C R,D S
Am{U
2.AB BC CD DAPQ QR RS SP
ABCD PQRS
ABCDE Am{U PQRST ‘ܶo
1. A P, B Q, C R, D S, E T
AB BC CD DE EAPQ QR RS ST TP
ABCDE PQRST
darb CXmhaUmdê$Z AmnU {ZîH$f© H$mT>Vmo H$s
gmaIrM ~mOy§Mr g§»¶m AgUmè¶m H$moU˶m ^m¡{‘{VH$ AmH¥$˶m AmhoV, ˶m :
(a) g‘ê$n AgVrb qH$dm AgUma Zm§hrV?
(b) Ho$ìhmM g‘ê$n ZgVmV.
AmVm Aem KQ>Zm§Mm {dMma H$ê$.
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266 UNIT-11
Q>rn : g§JV ~mOy§Mo JwUmoÎma ho ~hþ wOmH¥$VrgmR>r à‘mU KQ>H$ ‘mZbo OmVo.
OmUyZ ¿¶m !
{hëgMm {Z¶‘ : ^m¡{‘{VH$ÑîQ>çm g‘ê$n AgUmao àmUr g‘mZ C§MrMr CS>r ‘maVmV.
ñ’${Q>H$ê$nr {g{bH$m°Z hm {hè¶mer g‘mH¥${VH$ (Isomorphous) Amho. åhUOoM ˶m§Mr aMZm g‘ê$n Amho.
{ÌH$moUm§Mr g‘ê$nVm
EH$ê$n {ÌH$moUm‘ܶ| g§JV KQ>H$m§À¶m ghm OmoS>çm g‘mZ AgVmV ¶mMo ñ‘aU H$am. åhUOoM (i.e) g§JVH$moZm§À¶m VrZ OmoS>çm Am{U g§JV ~mOy§À¶m VrZ OmoS>çm. na§Vw H$moU˶mhr XmoZ {ÌH$moUm‘Yrb EH$ê$nVm {ZpíMVH$aʶmgmR>r Amåhr H$m§hr H$gmoQ>r {‘i{dboë¶m AmhoV H$s Á¶m‘ܶo {ÌH$moUmÀ¶m g§JV KQH$m§À¶m ’$º$ VrZOmoS>çm§Mm g‘mdoe Amho. ˶m åhUOo ~m-H$mo-~m, ~m-~m-~m Am{U H$mQ>H$moZ-H$U©- wOm H$gmoQ>r. Amåhr AgohrH$mT>bo Amho H$s Ooìhm XmoZ {ÌH$moU g‘H$moZ (AAA H$gmoQ>r) AgVrb Va Vo EH$ê$n AgVrb qH$dm AgUmaZmhrV.
Imbrb CXmhaUm§Mo {ZarjU H$am.
CXmhaU 1:
P
Q R
X
Y Z
P X, Q Y, R Z
PQ = XY, QR = YZ, PR = XZ
CXmhaU 2:P
Q R
X
Y Z
P = X, Q = Y, R = Z; PQ XY, QR YZ, PR XZ
CXmhaU 1 ‘ܶo : g§JV H$moZmÀ¶m gd© {VÝhr OmoS>çm Am{U g§JV ~mOyÀ¶m gd© {VÝhr OmoS>çm g‘mZ AmhoV.
PQR hm XYZ er EH$ê$n Amho åhUyZ PQR XYZ
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Similar Triangles 267
CXmhaU 2 ‘ܶo : g§JV H$moZm§À¶m gd© {VÝhr OmoS>çm g‘mZ AmhoV Am{U g§JV ~mOy§À¶m gd© {VÝhr OmoS>çmAg‘mZ AmhoV.
PQR hm XYZ er EH$ê$n Zm§hr.
Oa XmoZ {ÌH$moU g‘H$moZ AgyZ Vo EH$ê$n ZgVrb Va ˶m§À¶m g§JV ~mOy g‘mZ AgVrb qH$dm AgUma
Zm§hrV. Voìhm ˶m§À¶m g§JV ~mOy§Mo EH$‘oH$mer Agbobo ZmVo H$go Amho?
Imbrb g‘H$moZ {ÌH$moUm§À¶m OmoS>çm§Mo {ZarjU H$am. V³Ë¶m‘ܶo ˶m§À¶m g§JV ~mOy§Mr ‘mno {bhm.
4 cm
3 cm
2.5
cm
A
B C
8cm
6 cm
5 cm
P
Q R
A
B
C6 cm
9 cm
R
P Q
2cm
4 cm
3 cm12 cm
g‘H$moZ {ÌH$moU g§JV ~mOy§Mo JwUmoÎma
1. ABC Am{U PQRAB 2.5PQ 5
BCQR =
ACPR
=
2. ABC Am{U PQRABPQ =
BCQR =
ACPR =
darb à˶oH$ CXmhaUm‘ܶo ˶m§À¶m g§JV ~mOy§À¶m JwUmoÎmam{df¶r Vwåhr H$m¶ {ZîH$f© H$mT>mb?
Amåhr Ago {ZarjU H$aVmo H$s ˶m§Mr JwUmoÎmao g‘mZ AgVmV.
Oa JwUmoÎmao g‘mZ AgVrb Va ˶m§À¶m g§JV ~mOy à‘mUmV AmhoV Ago åhUVmV.
Amåhr Agm {ZîH$f© H$mT>Vmo H$s Oa XmoZ {ÌH$moU g‘H$moZ AgVrb Va ˶m§À¶m g§JV ~mOy à‘mUmV
AgVmV.
ho {MÝhmZo Ago Xe©{dbo OmVo. ABC Am{U DEF ‘ܶo
A
B C
D
E F
2.AB BC CADE EF FD
ABC ~ DEF
1. BAC = EDF ABC = DEF BCA = EFD
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268 UNIT-11
Q>rn: g‘ê$nVoMo ~ ho {MÝh Amho.
{ÌH$moU ho ’$º$ ~hþ wOmH¥$VrMo àH$ma AmhoV H$s OoWo g‘ê$n AmH¥$˶m§À¶m ì¶m»¶o‘ܶo {Xboë¶m XmoZ AQ>tMrnyV©Vm hmoV Zm§hr. Oa EImÚm AQ>rMr nyV©Vm hmoV Agob Va Vo {ÌH$moU g‘ê$n AgVmV.
XmoZ {ÌH$moUmZm g‘ê$n åhQ>bo OmVo, Oa
• ˶m§Mo g§JV H$moZ g‘mZ AgVmV qH$dm • ˶m§À¶m g§JV ~mOy à‘mUmV AgVmV
g‘mZ ~mOy§Mr g§»¶m AgUmè¶m XmoZ ~hþ wOmH¥$Vr g‘ê$n AgVmV.
Oa
AQ> 1 : gd© g§JV H$moZ g‘mZ AgVrb Va
AQ> 2 : gd© g§JV ~mOy gma»¶mM JwUmoÎmamV qH$dm à‘mUmV AgVrb Va
AmVm AmnU g‘ê$n {ÌH$moUm§À¶m g§JV H$moZ Am{U ~mOy ¶m§Mr MMm© H$ê$.
g§JV H$moZ : XmoZ g‘ê$n {ÌH$moUm‘ܶo Oo H$moZ g‘mZ AgVmV ˶mZm g§JV H$moZ åhUVmV.
Oa ABC ~ DEF
AB BC CADE EF FD
A = D Vo AZwH«$‘o g§JV ~mOy BC Am{U EF À¶m {dê$Õ AmhoV.
¶mMà‘mUo B = E Am{U C = F
g§JV ~mOy : g‘ê$n {ÌH$moUm‘ܶo g‘mZ H$moZm§À¶m {déÕ ~mOyg AgUmè¶m ~mOyZm g§JV ~mOy åhUVmV
Am{U ˶m à‘mUmV AgVmV.
AB Am{U DE g§JV ~mOy AmhoV H$maU ˶m AZwH«$‘o C Am{U F ¶m g‘mZ H$moZm§À¶m {dê$Õ AmhoV.
VgoM,BC Am{U EF g§JV ~mOy AmhoV
CA Am{U FD g§JV ~mOy AmhoV
{ÌH$moUm§Mr EH$ê$nVm Am{U g‘ê$nVm (Congruency and Similarity of Triangles)
EH$ê$nVm hr g‘ê$nVoMr {d{eï> KQ>Zm Amho. XmoÝhr KQ>Zo‘ܶo EH$m {ÌH$moUmMo {VÝhr H$moZ Xþgè¶m
{ÌH$moUmÀ¶m VrZ g§JV H$moZm~amo~a AgVmV. EH$ê$n {ÌH$moUm‘ܶo g§JV ~mOy g‘mZ AgVmV Va g‘ê$n
{ÌH$moUm‘ܶo g§JV ~mOy à‘mUmV AgVmV.
A
B C
D
E F
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Similar Triangles 269
3. PQR, ‘ܶo PQ da S hm Agm q~Xÿ Amho H$s
ST||QR Am{UPS 3= .SQ 5 Agob.
EH$ê$n {ÌH$moU g‘ê$n {ÌH$moU
A
B C
D
E F
A
B C
D
E F
ABC DEF ABC ~ DEF
A = D, B = E, C = F A = D, B = E, C = F
AB = DE; BC = EF; CA = FD AB DE; BC EF; CA FD
AB BC CA 1DE EF FD
AB BC CA1 < 1
DE EF FD
gmaImM AmH$ma Am{U gmaIoM ‘mn gmaImM AmH$ma na§Vw doJio ‘mn
Amåhr Agmhr {ZîH$f© H$mT>Vmo H$s,
'EH$ê$n {ÌH$moU Zoh‘r g‘ê$n AgVmV.
na§Vw 'g‘ê$n {ÌH$moU ho EH$ê$n AgVrbM Ago Zmhr.
ñnï>rH$aUmË‘H$ CXmhaUo
{ÌH$moUmÀ¶m g‘ê$nVoda AmYm[aV g§»¶mË‘H$ CXmhaUo
CXmhaU 1: ~mOyÀ¶m AmH¥$VrV PQR TSR.
g§JV {eamoq~Xÿ, g§JV ~mOy Am{U ˶m§Mr JwUmoÎmao AmoiIm.
CH$b :
{Xbobo PQR TSR
g§JV {eamoq~Xÿ g§JV ~mOy
P T Q R R S
Q S P R R T
R R P Q S T
JwUmoÎmao hr
P
Q
R
S
T
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270 UNIT-11
PQ QR PRST RS RT
CXmhaU 2 : Imbrb ‘m{hVrdê$Z ABC DEF g‘ê$n AmhoV qH$dm ZmhrV ho ñnï> H$am Oa
(a) B = 650, C = 820, D = 330 , F = 650
CH$b :
ABC ‘ܶo, B = 650, C = 820.
A = 1800 (650 + 820) = 1800 1470 = 330.
DEF ‘ܶo, D = 330 , F = 650
E = 1800 – (330 + 650) = 1800 – 980 = 820.
A = D, B = F Am{U C = E.
ABC DEF
ñdmܶm¶ 11.1
1. Imbr {Xboë¶m g‘ê$n {ÌH$moUmÀ¶m OmoS>çm‘ܶo, g§JV {eamo[~§Xÿ g§JV ~mOy Am{U ˶m§Mr JwUmoÎmao {bhm.
(a)
BA
C
(b)
P Q K
L
M
Z
X
Y
c( )
A
B
D
EC
2. Imbrb AmH¥$˶m§Mm Aä¶mg H$am Am{U à˶oH$mÀ¶m ~m~VrV {ÌH$moU g‘ê$n hmoVmV H$m¶ Vo gm§Jm. H$maUoÚm
A
D
E
BC
75°
a
F
a
a55°
D
HG
F E
80°
60°
40°
(ii)
M
P
N OQ
2 cm
6 cm6cm
8 cm2 cm
4 cm
X
U V
Y Z
a
b60°
60°3 b
(iii) (iv)
2a
c
2c
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Similar Triangles 271
3. Imbrb ‘m{hVrdê$Z ABC hm DEF bm g‘ê$n Amho H$s Zmhr ho ñnï> H$am.
(a) A = 700, B = 800, D = 700, F = 300
(b) AB = 8 g|§.‘r, BC=9g|§.‘r, CA=15 g|§.‘r, DE=4 g|§.‘r, EF=3g|§.‘r, FD=5 g|§.‘r.
4 Imbrb g§»¶m‘ܶo g‘ê$n {ÌH$moU hmoʶmgmR>r g§»¶mMo gQ> {ZdS>m.
(i) 3,4,6 (ii) 9, 12, 18 (iii) 8, 6, 12 (iv) 8, 4, 9(v) 2, 4½, 4
à‘mUmdarb ‘yb^yV ^m¡{‘{VH$ n[aUm‘ :
H¥$Vr : Imbrb {ÌH$moUm§Mm H$miOrnyd©H$ Aä¶mg H$am. ABC, ‘ܶo BC bm g‘m§Va DE H$mT>bm. aofmI§S> AD,
DB, AE Am{U CE À¶m ‘mnm§Mo {ZarjU H$am. AmVm Ago ‘mZm H$s XmoZ ~mOy§À¶m JwUmoÎmamZm DE Zo ^mJ OmVmo.
¶m JwUmoÎmam{df¶r Vwåhr H$m¶ {ZîH$f© H$mTy eH$mb?
JQ>m‘ܶo ¶mMr MMm© H$am.
ABC, ‘ܶo DE || BC
AD 2 1DB 6 3
AE 1.5 1EC 4.5 3
AD AE 1DB EC 3
ABC, ‘ܶo DE || BC
AD 6 2DB 3
AE 4 2EC 2
AD AE 2DB EC
ABC, ‘ܶo DE hr BC ~mOybm g‘m§Va Zm§hr
A
B C
D E
5 cm
6cm
4.5
cm
1.5 cm2 cm
Fig. 1A
B C
D E
4cm
2 cm3 cm
6 cm
5 cm
AmH¥$Vr 2
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272 UNIT-11
AD 2 1DB 4 2
AE 2 1EC 6 3
AD AEDB EC
n{hë¶m XmoZ {ÌH$moUm‘ܶo à˶oH$ JwUmoÎma g‘mZ Amho nU {Vgam {ÌH$moUm‘ܶo JwUmoÎma g‘mZ Zm§hrV. åhUyZ
ABC ‘ܶo JwUmoÎma g‘mZ hmoʶmgmR>r H$moUVr ‘hËdmMr AQ>/H$gmoQ>r Amho?
{dMma H$am!
ABC, ‘ܶo EH$M ‘hËdmMr AQ> Amho. DE hr BC bm g‘m§Va Amho Am{UADDB d
AEEC hr JwUmoÎma g‘mZ
AmhoV.
darb {ZîH$f m©Mo gm‘ mݶrH$aU Ho$b ob o A mho ˶mb m ‘ yb ^ yV à‘ mUmMm à‘ o¶ (B.P.T) qH$dm WoëgMm à‘o¶
åhUVmV. ho Ago ñnï> H$aVmV.
"{ÌH$moUmÀ¶m EH$m ~mOyg g‘m§Va AgUmar aofm BVa XmoZ ~mOyZm N>oXV Agob Va Vr aofm ˶m ~mOyZm
à‘mUmV {d^mJVo ".
VH©$ewÕ nÕVrZo AmVm WoëgMm à‘o¶ {gÕ H$ê$.
WoëgMm à‘o¶ : (‘yb^yV à‘mUmMm à‘o¶)-1 (Basic propertionality Theorem)
{ÌH$moUmÀ¶m EH$m ~mOyg g‘m§Va AgUmar aofm BVa XmoZ ~mOyZm N>oXV Agob Va Vr aofm ˶m ~mOyZm à‘mUmV
{d^mJVo.
J¥hrV : ABC ‘ܶo
DE || BC
gmܶ :AD AEDB EC
aMZm : DC Am{U EB OmoS>m EF AB Am{U DN AC H$mT>m.
A
B C
D
E
6cm
5 cm
4cm
2 cm 2 cm
AmH¥$Vr 3
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Similar Triangles 273
{gÕVm: {dYmZ H$maU
ADE ADBDE DB
ADE ADBDE DB
ADE AECDE EC
ADE AECDE EC
AD AEDB CE
BDE CDE -1Am{U ‘yb VËd
WoëgMm à‘o¶ {gÕ H$aVmZm XmoZ A{YH$ nÕVrZo AmH¥$Vr H$mT>Vm ¶oVo.
AmH¥$Vr 1 AmH¥$Vr 2
A
B C
DE A
B C
D E
WoëgÀ¶m à‘o¶mMm ì¶Ë¶mg
"Oa EH$ gaiaofm {ÌH$moUmÀ¶m XmoZ ~mOyZm à‘mUmV N>oXV Agob Va Vr gaiaofm {Vgè¶m ~mOybm g‘m§Va
AgVo".
J¥hrV : ABC ‘ܶoAD AEDB EC
gmܶ : DE || BC
aMZm: BF || DE H$mT>m
A
B C
DL N
E
( gma»¶mM C§MrÀ¶m {ÌH$moUmMo joÌ’$i
g§JV nm¶mÀ¶m à‘mUV AgVoo.)
12 AD EL12 DB EL
12 AE DN
12 ECX DN
A
B C
D E
F
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274 UNIT-11
A
B C
D E
{gÕVm : {dYmZ H$maU
ABC ‘ܶo DE || BF (aMZm)
AD AEDB EF
[WoëgMm à‘o¶]
na§V wAD AEDB EC [J¥hrV]
AE AEEC EF
EC = EF
F q~Xÿ C [~§Xÿer V§VmoV§V OwiVmo.
åhUyZ, DE || BC
AmVm AmnU WoëgÀ¶m à‘o¶mÀ¶m H$m§hr Cn{gÕm§Vm§Mm Aä¶mg H$ê$.
Cn{gÕm§V :1
ABC ‘ܶo DE || BC
AD AEDB EC
[ ‘y.à.à‘o¶]
XmoÝhr ~mOy‘ܶo 1 {‘idm
AD AE1 1DB EC
AD DB AE ECDB EC
AB ACDB EC ømbm Componendo Ago åhUVmV.
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Similar Triangles 275
Cn{gÕm§V 2 :
ABC ‘ܶo DE || BC
AD AEDB EC
[ ‘y.à.à‘o¶]
ì¶ñV KoD$Z Amåhmbm {‘iVo
DB ECAD AE
XmoÝhr ~mOy‘ܶo 1 {‘idm
DB EC1 1AD AE
DB AD EC AEAD AE
AB ACAD AE
ømbm Componendo Ago åhUVmV.
Cn{gÕm§V 3 :
ABC ‘ܶo DE || BC Am{U EF || AB
DEFB g‘m§Va wOMm¡H$moZ [ g‘m§Va^wO Mm¡H$moZmMr ì¶m»¶m]
BF = DE [ g‘m§Va wO Mm¡H$moZm‘ܶo {dê$Õ ~mOy g‘mZ
AgVmV.]
ABC ‘ܶo DE || BCAD AEAB AC
[ Cn{gÕm§V-1]
ABC ‘ܶo EF || ABBF AEBC AC
[ Cn{gÕm§V 2]
DE AEBC AC
[ BF = DE]
AD DE AEDB BC AC
A
B C
D E
F
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276 UNIT-11
{Q>n : gd© {VÝhr Cn{gÕm§VmMm ì¶Ë¶mg AmT>iVmo Am{U Vmo g˶ Amho.
Cn{gÕm§V 3 Mo {dYmZ Imbrbà‘mUo Amho. Oa {ÌH$moUmÀ¶m EH$m ~mOybm g‘m§Va AgUmar aofm H$mT>br Va
N>oXH$ {ÌH$moUmÀ¶m ~mOy ‘yi {ÌH$moUmÀ¶m ~mOyer à‘mUmV AgVmV.
WoëgÀ¶m à‘o¶mda AmYmarV àm¶m{JH$ CXmhaUo
{Xboë¶m JwUmoÎmamV aofoMo ^mJ H$aUo.
AB = 14 g|.‘r aofmI§S>mM o 2 : 5 JwUmoÎmamV ^mJ H$am.
A 4 cm
N
M
P
BC 10 cm14 cm
2 cm
5 cm
nm¶è¶m : 1. AB = 14 g|.‘r H$mT>m.
2. AB er H$moU˶mhr ‘mnmMm H$moZ H$aUmam AP H$mT>m.
[g‘Om gmo¶rgmR>r PAB < 600]
3. AP da M Am{U N Aem IwUm H$am H$s AM = 2 g|.‘r, d MN = 5 g|.‘r hmoVrb.
4. N Am{U B OmoS>m.
5. {ÌH$moUr Jwʶm (set squares) dmnê$Z MC || NB H$mT>m.
6. AC Am{U CB ‘moOm. AC = ___ g|.‘r CB = ___ g|.‘r
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Similar Triangles 277
WoëgMm à‘o¶ dmnê$Z darb n[aUm‘ Imbrb H$m§hr nm¶è¶mdê$Z {gÕ H$aVm ¶oVmo.
J¥hrV : ABN ‘ܶoAM 2MN 5 , Am{U MC || NB
gmܶ :AC 2CB 5
{gÕVm : ABN ‘ܶo MC || NB
AM AC 2=MN CB 5
[ WoëgMm à‘o¶]
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1 : ABC ‘ܶo DEIIBC, AD = 5.7 g|.‘r, BD = 9.5g|.‘r, EC = 6g|.‘r.Va AE H$mT>m.
CH$b :
{Xb ob o : ABC ‘ܶo DE || BC
AD AEDB EC ( ‘y.à.à‘o¶)
5.7 AE9.5 6
5.7 6AE9.5
AE = 3.6 g|.‘r
CXmhaU 2 : eoOmarb AmH¥$VrV XY II BC.
AX = p-3, BX =2p-2 Am{UAY 1= .CY 4 Va P H$mT>m.
CH$b :
{Xbobo : ABC ‘ܶo XY || BC
AX AYXB YC ( WoëgMm à‘o¶)
A
E
9.5
cm.
D
CB
5.7
cm.
6cm
.
?
A B
C
X
Y
p-3 2p-2
4
1
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278 UNIT-11
3 12 2 4pp
4 (p-3) = 1(2p-2)
4p-12=2p-2
2p = 10
p = 5
CXmhaU 3. PQR, ‘ܶo S Am{U T ho XmoZ q~Xÿ AZwH«$‘o PQ Am{U PR da Ago AmhoV H$s PS = 4g|.‘r, SQ
= 3g|.‘r, PT = 6g|.‘r, TR = 4.5g|.‘r Am{U PST = 400. PQR H$mT>m.
CH$b :
PQR ‘ܶoPS 4=SQ 3PT 6 4TR 4.5 3
PS PTSQ TR
ST || QR
( WoëgÀ¶m à‘o¶mMm ì¶Ë¶mg)
PST = PQR = 400
CXmhaU 4: ABC ‘ܶo g‘ wO Mm¡H$moZ PQRB hm Am§Va{b{IV H$obobm Amho. H$s B hm EH$ ˶mMm H$moZ
hmoB©b. P,Q Am{U R ho AZwH«$‘o AB, AC Am{U BC da q~Xÿ AmhoV. Oa AB = 12 g|.‘r. Am{U BC = 6
g|.‘r Va PQRB g‘ wO Mm¡H$moZmÀ¶m ~mOy H$mT>m.
{dYmZ H$maU
CH$b : ABC, PQ || BC g‘ wO Mm¡H$moZm‘ܶo g§‘wI ~mOy g‘m§Va AgVmV.
AP PQAB BC
$WoëgMm Cn{gÕm§V
P
T
3cm
S
RQ
6 cm4cm
400
4.5 cm?
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Similar Triangles 279
1212 6
x x
12x = 72 – 6x
18x = 72
x = 4 $g|‘r.
$g‘ wO Mm¡H$moZmMr à˶oH$ ~mOy 4 g|.‘r Amho.
CXmhaU 5. {XdgmÀ¶m EH$m {ZpíMV doir 6 ’y$Q> C§MrÀ¶m ‘mUgmMr gmdbr 8 ’y$Q> bm§~ nS>Vo. ˶mM doir 45’y$Q> C§MrÀ¶m B‘maVrMr gmdbr {H$Vr bm§~rMr Agob?
CH$b :
B‘maVrÀ¶m gmdbrMr bm§~rx Amho Ago ‘mZy
Á¶mAWu DE || AC, DBE ABC.
åhUOoM
‘mUgmMr C§Mr ‘mUgmÀ¶m nS>boë¶m gmdbrMr bm§~r
B‘maVrMr C§Mr B‘maVrÀ¶m nS>boë¶m gmdbrMr bm§~r
’y$Q>’y$Q>
’y$Q>6 845 x
’y$Q>8 45 60
6x
B‘maVrÀ¶m nS>boë¶m gmdbrMr bm§~r 60 ’y$Q> Amho.
CXmhaU 6 : PQR ‘ܶo 2PM = 3 PN Am{U 2PQ = 3PR
{gÕ H$am MQRN hm g‘b§~ Mm¡H$moZ Amho.
{gÕVm : (i)2PM 3PN2PQ 3PR
[ J¥hrV]PM PNPQ PR
||MN QR [ ‘y.à.à‘o¶mMmì¶Ë¶mg]
A
xP Q
B R
x
x
x
C
A
CB
D6ft
Ex
8ft
45ft
=
M N
P
Q R
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280 UNIT-11
(ii) Á¶m AWu QP Am{U RP ,hr 'P' ‘ܶo N>oXVmV, ˶m AWu
QP hr RP bm g‘m§Va AgUma Zm§hrV.
MQRN hm g‘b§~ Mm¡H$moZ Amho.
CXmhaU 7: {gÕ H$am H$s g‘b§~ Mm¡H$moZm‘ܶo Ag‘m§Va ~mOy§Mo ‘ܶ OmoS>Umar
aofm (i) g‘m§Va ~mOyZm g‘m§Va AgVo - Am{U
(ii) g‘m§Va ~mOy§À¶m ~oaOoÀ¶m {Zå‘r AgVo.
J¥hrV : ABCD g‘b§~ Mm¡H$moZm‘ܶo(i) AD || BC
(ii) AX = XB(iii) DY = YC
gmܶ : (i) XY II AD
qH$dm XY IIBC
(ii)1
XY (AD BC)2
= +
aMZm : 1. BA Am{U CD Aem dmT>dm H$s ˶m Z ‘ܶo {‘iVrb
2. A Am{U C OmoS>m XY bm P ‘ܶo N>oXVo.
{gÕVm : nm¶ar 1: ZBC ‘ܶo
ADII BC [ J¥hrV]
ZA ZDAB DC
= [ ‘y.à.à‘o¶ ]
ZA ZD2AX 2DY
= [ X Am{U Y ho AB Am{U DC Mo
‘ܶq~Xÿ AmhoV.]
ZA ZDAX DY
=
XY || AD ---(i) [ ‘y.à.à‘o¶mMm ì¶Ë¶mg]
nm¶ar 2: ABC ‘ܶo
1. AX = XB [ J¥hrV]
2. XP || BC [ {gÕ]
AP = PC [ ‘ܶ-q~Xÿ à‘o¶mMm ì¶Ë¶mg]
XP = ½ BC [ ‘ܶ-q~Xÿ à‘o¶]
Z
A
B C
DP YX
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Similar Triangles 281
||| ly In ADC, PY = ½AD
{‘idyZ AmnUmg {‘iVo XP + PY = ½BC + ½AD
XY = ½ (BC + AD) --- (ii)
hr g‘ñ¶m n¶m©¶r aMZm H$ê$Z XoIrb gmoS>{dVm ¶oVo.
CXmhaUmW© AC OmoS>ʶmEodOr DE II AB H$mT>m. Vr XY bm P ‘ܶo N>oXVo.
AmVm, JQ> H$ê$Z MMm© H$am Am{U {gÕVm {bhm.
ñdmܶm¶ 11.2
A WoëgÀ¶m à‘o¶mda AmYmarV g§»¶mË‘H$ CXmhaUo.
1.~mOyÀ¶m AmH¥$VrMm Aä¶mg H$am.
‘yb yV à‘mUmÀ¶m à‘o¶mda Am{U
˶mÀ¶m Cn{gÕm§Vmer g§~§{YV JwUmoÎmao
a, b, c Am{U d À¶m ñdê$nmV {bhm.
2.~mOyÀ¶m AmH¥$Vr‘ܶ o DE||AB, AD = 7g|.‘r., CD = 5g|.‘r. Am{U BC
= 18g|.‘r. BE Am{U CE H$mT>m.
3. ABC ‘ܶo ~mOy AB Am{U AC da AZwH«$‘ o D Am{U E Ago q~Xÿ AmhoVH$s DE||BC hmoB©b.
(i) Oa AD = 6g|.‘r, DB = 9g|.‘r, Am{U AE = 8g|.‘r, Va AC H$mT>m.
(ii) Oa AD = 8g|.‘r, AB = 12g|.‘r, AE = 12g|.‘r, Va CE. H$mT>m.
(iii) Oa AD = 4x-3, BD = 3x-1, AE = 8x-7, CE =5x-3 Va x Mr qH$‘V H$mT>m.
4. PQR ‘ܶo PQ Am{U PR ~mOyda AZwH«$‘o E Am{U F q~Xÿ AmhoV. Imbrb à˶oH$ KQ>ZogmR>r EF||QR
nS>VmiyZ nhm.
A
B CE
DX YP
Z
P Q
R
X
Y
a b
c
d
C
ED
BA
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282 UNIT-11
(i) PE = 3.9g|.‘r, EQ = 3g|.‘r, PF = 3.6g|.‘r, FR = 2.4 g|.‘r.
(ii) PE = 4g|.‘r, QE = 4.5g|.‘r, PF = 8g|.‘r, FR = 9g|.‘r.
(iii) PQ = 1.28g|.‘r, PR = 2.56g|.‘r, PE = 0.18g|.‘r,
PF = 0.36g|.‘r.
5.eoOmarb AmH¥$Vr‘ܶ o AC||BD Am{U CE||DF.
Oa OA = 12 g|.‘r, AB = 9 g|.‘r, OC = 8 g|.‘r Am{U EF =
4.5 g|.‘r Va OE H$mT>m.
6.AmH¥$Vr‘ܶo PC||QK Am{U BC||HK. Oa
AQ = 6g|.‘r, QH = 4g|.‘r, HP = 5g|.‘r Am{U KC = 18g|.‘r,
Va AK Am{U PB H$mT>m.
7.{XdgmÀ¶m EH$m {ZpíMV doir EH$m PmS>mMr gmdbr 12.5 ’y$Q> bm§~ nS>Vo. Oa
PmS>mMr C§Mr 5 ’y$Q> Agob Va ˶mM doir 20 ’y$Q> bm§~ gmdbr
nmS>Umè¶m PmS>mMr C§Mr {H$Vr Agob?
8. Cä¶m q^Vrbm EH$ {eS>r Q>oH$bobr AgyZ q^VrnmgyZ 6 ’y$Q> A§Vamda {eS>rMo Xþgao Q>moH$ O{‘Zrda Amho.
O{‘Zrdarb EH$ ‘mUyg {eS>rda XmoZ V¥{VAm§e ^mJ MT>Vmo Va ˶mMo {eS>rnmgyZMo AmVmMo A§Va H$mT>m.
B WoëgÀ¶m à‘o¶mMr àm¶mo{JH$ Cn¶mo{JVm :
1. ABC À¶m AmV x hm H$moUVmhr q~Xÿ Amho XA, XB Am{U XC
OmoS>m. AX d 'E' hm H$moUVmhr q~Xÿ Amho. Oa EF II AB, FG II BC Va
{gÕ H$am H$s ||EG AC . (gyMZm : ‘y.à.à‘o¶ Am{U ‘ybVËd).
O
CA
DB
E
F
A
KQ
CB
H
P
A
B C
E
F G x
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Similar Triangles 283
2. ABC ‘ܶo, B = C, AB Am{U AC da D Am{U E Ago q~Xÿ
AmhoV H$s BD CE {gÕ H$am DE II BC.
3 ABC, ‘ܶo, PQ || BC Am{U BD || DC,
{gÕ H$am PE || EQ
(gyMZm : ABC ‘ܶo AD ‘ܶJm BC bm g‘m§Va AgUmè¶m aofobmXþ^mJVo).
4. AmH¥$VrV PR || BC Am{U QR || BD
{gÕ H$am, PQ || CD.
5. ABC ‘ܶo DE || BC Am{U CD || EF {gÕ H$am
AD2 = AF × AB
{ÌH$m oUm §À¶m g‘ê$nVogmR>rÀ¶m H$gm oQ >r
{ÌH$moUm§Mr EH$ê$nVm R>a{dʶmgmR>r Amnë¶mH$S>o {ZpíMV H$gmoQ>r AmhoV ho AmR>dm. AemM àH$mao
{ÌH$moUm§Mr g‘ê$nVm Ca{dʶmgmR>r H$moUVr H$gmoQ>r Agob? XmoÝhr {ÌH$moUm§À¶m g§JV KQ>H$m§À¶m ghm OmoS>çm
VnmgʶmMr Amdí¶H$Vm Amho H$m? XmoZ {ÌH$moUm§À¶m g‘ê$nVogmR>rÀ¶m H$gmoQ>rMm Aä¶mg H$ê$. ¶m H$gmoQ>tMm
H¥$Vr H$ê$Z emoY bmdy.
XmoZ {ÌH$moUmgmR>r H$moZ-H$moZ (AA) g‘ê$nVm H$gmoQ>r
Amnë¶mbm ‘m{hV Amho H$s Oa EH$m {ÌH$moUmMo XmoZ H$moZ Xþgè¶m {ÌH$moUmÀ¶m XmoZ g§JV H$moZm~amo~a
AgVrb Va {ÌH$moUmÀ¶m H$moZm§À¶m ~oaOoÀ¶m JwUY‘m©dê$Z ˶m§Mm {Vgam H$moZ XoIrb g‘mZ AgVmo. åhUyZ AAA
A
B C
D E
A
B CD
EP Q
A B
C
D
R
P
Q
A
B C
D E
F
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284 UNIT-11
g‘ê$nVm H$gmoQ>r Aem àH$mao gm§JVm ¶oVo. ""Oa EH$m {ÌH$moUmMo XmoZ H$moZ Xþgè¶m {ÌH$moUmÀ¶m XmoZ g§JV
H$moZm~amo~a AgVrb Va XmoZ {ÌH$moU g‘ê$n AgVmV''. ¶mMm C„oI XmoZ {ÌH$moUmMr g‘ê$nVm H$gmoQ>r Agm
H$aVm ¶oB©b.
ho ñnï>nUo Ago gm§JVm ¶oVo. "XmoZ {ÌH$moUm‘ܶo Oa g§JV H$moZ g‘mZ AgVrb Va ˶m§À¶m g§JV ~mOy
à‘mUmV AgVmV Am{U åhUyZ XmoZ {ÌH$moU g‘ê$n AgVmV".
qH$dm
Oa XmoZ {ÌH$moU g‘H$moZ AgVrb Va ˶m§À¶m g§JV ~mOy à‘mUmV AgVmV.
AmVm ho {dYmZ VH©$ewÕ nÕVrZo {gÕ H$ê$.
à‘o¶ (H$moZ-H$moZ g‘ê$nVm H$gmoQ>r)
"Oa XmoZ {ÌH$moU g‘H$moZ AgVrb Va ˶m§À¶m g§JV ~mOy à‘mUmV AgVmV".A
B C
G H
D
E F
J¥hrV : ABC Am{U DEF ‘ܶo
(i) BAC = EDF
(ii) ABC = DEF
gmܶ : AB BC CADE EF FD
aMZm : AB Am{U AC da 'G' Am{U 'H' q~XÿÀ¶m Aem IwUm H$am H$s
(i) AG = DE Am{U (ii) AH = DF . G Am{U H OmoS>m.
{gÕVm : {dYmZ H$maU
AGH Am{U DEF ‘ܶo
AG = DE [ aMZm ]
GAH = EDF [ J¥hrV]
AH = DF [ aMZm]
AGH DEF [ SAS J¥hrVH$ ]
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Similar Triangles 285
AGH = DEF [ CPCT]
na§Vw ABC = DEF [ J¥hrV]
AGH = ABC [ ‘ybVËd-1]
GH || BC [ Oa g§JV H$moZ g‘mZ AgVrb Va
aofm g‘m§Va AgVmV.]AB BC CAAG GH HA [ WoëgÀ¶m à‘o¶mMm Cn{gÕm§V]
åhUyZAB BC CADE EF FD
[ AGH DEF]
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU ABC ‘ܶo, AL, BM Am{U CN ho {eamob§~ 'O' ‘ܶo {‘iVmV.
{gÕ H$am (i) AMB ~ ANC (2)AN BL CM. . = 1BN CL AM
CH$b :
J¥hrV ({Xbobo) : ABC ‘ܶo AL, BM Am{U
CN ho {eamob§~ AmhoV.
gmܶ : (i) AMB ~ ANC
(ii)AN BL CM. . 1BN CL AM
{gÕVm : ‘ܶo AMB Am{U ANC
AMB ANC 90 ( J¥hrV)
BAM NAC ( g‘mB©H$ H$moZ)
AMB ~ ANC ( AA H$gmoQ>r)
˶mMà‘mUo BLA ~ BNC
Am{U BMC ~ ALC
O
A
B C
NM
L
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286 UNIT-11
AMB ~ ANCAN ACAM AB
BLA ~ BNCBL ABBN BC
BMC ~ ALCCM BCCL AC
AN BL CM AC AB BCAM BN CL AB BC AC
AN BL CM 1BN LC AM
qH$dm AN × BL × CM = BN × LC × AM
CXmhaU 2. ABCD g‘b§~ Mm¡H$moZm‘ܶo (i) AB || DC (ii) AED ~ BEC Va {gÕ H$am H$s AD=BC
J¥hrV : ABCD g‘b§~ Mm¡H$moZm‘ܶo
(i) AB||DC(ii) AED ~ BEC
gmܶ : AD=BC
{gÕVm : EDC Am{U EBA Mr VwbZm H$ê$Z
EDC = EBA [ || DC Am{U ì¶wËH«$‘ H$moZ ]
ECD = EAB
EDC ~ EBA g‘H$moZ {ÌH$moU ]
ED ECEB EA
[ H$mo.H$mo.]
ED EBEC EA
nU AED BEC [ J¥hrV ]
ED EA ADEC EB BC
[ H$mo.H$mo.]
EB EAEA EB [ ‘wiVËd]
EA2 = EB2
EA = EB
A B
CD
E
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Similar Triangles 287
EA AD 1EB BC
AD = BC
ho OmUyZ ¿¶m
"{ÌH$moUmÀ¶m H$moU˶mhr XmoZ ~mOy§Mm g‘mdoe AgUma Am¶V hm {ÌH$moUmÀ¶m
{Vgè¶m ~mOydarb {eamob§~ Am{U n[aì¶mgmMm (circum
diameter) g‘mdoe AgUmè¶m Am¶Vm ~amo~a AgVmo." ho {gÕ
H$am.
J¥hrV : ABC ‘ܶo AX BC
O hm ABC Mm n[a‘ܶ Amho.
AE hm ì¶mg Amho.
gmܶ : AB.AC = AX.AE
aMZm : E Am{U C OmoS>m.
{gÕVm : AXB Am{U AEC ¶m§Mr VwbZm H$am
AXB ACE 90
ABX AEC [ AY© dVw©iI§S>mVrb H$moZ H$mQ>H$moZ AgVmo.]
AXB ||| ACE [ EH$mM dVw©i I§S>mVrb H$moZ]AX ABAE AC
[ g‘H$moZ {ÌH$moU ]
AB.AC = AX.AE [H$mo.H$mo.H$gmoQ>r]
ñdmܶm¶ 11.3
A A A g‘ê$nVm H$gmoQ>rda AmYm[aV Cnà‘o¶
{Xboë¶m AmH¥$Vr‘ܶo AE || DB, BC = 7 go.‘r BD=5 go.‘r
DC = 4 go.‘r Oa CE=12 go.‘r Va AE Am{U AC H$mT>m.
O
A
B C
E
X
go§.‘r
go§.‘r
go§.‘r
go§.‘r
12
A BC
D
E
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288 UNIT-11
2. XYZ ‘ܶo P hm XY darb H$moUVmhr EH$ q~Xÿ Amho Am{U
PQ XZ Oa XP = 4 g|‘r, XY=16 g|‘r, Am{U
XZ =24 g|‘r, Va XQ H$mT>m.
3. 90 g|.‘r C§Mr AgUmar ‘wbJr 1.2 ‘r/go doJmZo {Xì¶mÀ¶m
Im§ã¶mÀ¶m VimnmgyZ Xÿa Mmbbr Amho. Oa {Xdm O{‘ZrnmgyZ
3.6 ‘r. da Amho, 4 goH§$XmZ§Va gmdbrMr bm§~r H$mT>m.
B A A g‘ê$nVm H$gmoQ>rda AmYm[aV Cnà‘o¶
1. BAC Am{U BDC ¶m XmoZ H$mQ>H$moZ {ÌH$moUm‘ܶo g‘mB©H$
H$U© BC Amho. ~mOy AC Am{U BD ho 'P' ‘ܶo N>oXVmV.
Va {gÕ H$am H$s AP. PC = DP. PB
2. PQR Am{U TUS ‘ܶo
QPR = UTS = 900 Am{U
PR||TS $Va
{gÕ H$am PQR ~ TUS
3. Mm¡H$moZmMo H$U© EH$‘oH$mZm à‘mUmV {d^mJVmV Va Vmo Mm¡H$moZ g‘b§~ Mm¡H$moZ Amho ho {gÕ H$am.
4.||gm ABCD Mm H$U© BD, hm AE bm 'F' ‘ܶo
N>oXVmo.
'E' hm BC da H$moUVmhr q~Xÿ Amho.
{gÕ H$am DE.EF = FB. FA
5. eoOmaÀ¶m AmH ¥ $VrV ABC 90 Am{U
AMP 90
{gÕ H$am.
(i) ABC AMP
X
Z
QP
Y
A
B C
D
P
P
Q RS
T
U
A B
CD
EF
A B
C
P
M
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Similar Triangles 289
(ii)CA BCPA MP
6. g‘b§~ Mm¡H$moZ ABCD ‘ܶo
||AB DC
||EF AB Am{U =DC 2ABBE 3EC 4
{gÕ H$am H$s 7EF 10AB
XmoZ {ÌH$moUm§Mr (SSS) g‘ê$nVm H$gmoQ>r
Vwåhr ‘mJÀ¶m à‘o¶m‘ܶo nm{hbo Amho H$s Oa EH$m {ÌH$moUmMo VrZ H$moZ (AAA) Xþgè¶m {ÌH$moUmÀ¶m VrZ
g§JV H$moZm~amo~a (AAA) AgVrb Va ˶m§À¶m g§JV ~mOy (SSS) à‘mUmV AgVmV.
AmVm ¶m {dYmZmMm ì¶Ë¶mg ñnï>nUo gm§Jy
"Oa EH$m {ÌH$moUmÀ¶m VrZ ~mOy (SSS) Xþgè¶m {ÌH$moUmÀ¶m VrZ g§JV ~mOy§À¶m (SSS) à‘mUmV
AgVrb, Va ˶m§Mo g§JV H$moZ (AAA) g‘mZ AgVmV".
XmoZ {ÌH$moUmgmR>r ~mOy-H$moZ-~mOy (SAS) g‘ê$nVm H$gmoQ>r
"Oa EH$m {ÌH$moUmÀ¶m XmoZ ~mOy Xþgè¶m {ÌH$moUmÀ¶m XmoZ ~mOy§er à‘mUmV AgVrb Am{U XmoZ ~mOy‘ܶo
AgUmam H$moZ g‘mZ Agob Va Vo XmoZ {ÌH$moU g‘H$moZ AgVmV Am{U åhUyZ g‘ê$n AgVmV."
ñdmܶm¶ 11.4
1. Imbrb H$moU˶m KQ>Zm‘ܶo {ÌH$moUm§À¶m OmoS>çm g‘ê$n AmhoV ?
àýmMo CÎma XoʶmgmR>r Vwåhr H$moUVr g‘ê$nVm H$gmoQ>r dmnabr Amho Vo {bhm Am{U g‘ê$n {ÌH$moUm§À¶m
OmoS>çm {MÝhm§À¶m ñdê$nmV {bhm.
AmH¥$Vr1
A
B C
D
E F
60°
40° 40°
60°
A
B C
D
E F15 cm5 cm
6.9
cm2.
3c
m
124 cc mm
AmH¥$Vr 2
CD
EF G
A B
CD
EF G
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290 UNIT-11
AmH¥$Vr 3
W X
YZ
77
4 4O
AmH¥$Vr 4
H J5
46
D
E F
3
2
AmH¥$Vr 5
H
M L
A12.5
5
10 4
3
T
AmH¥$Vr 6
X
Y Z
80°2.5
3
T
U V6
5
80°
à‘o¶ : H$mQ>H$moZ {ÌH$moUm‘ܶo H$mQ>H$moZ {eamoq~XÿVyZ H$Um©da H$mT>bobm b§~ H$mQ>H$moZ {ÌH$moUmg XmoZ ‘yi
{ÌH$moUmer g‘ê$n AgUmè¶m {ÌH$moUmV {d^mJVmo.
J¥hrV : ABC, ‘ܶo (i) ABC = 90°.
(ii) BD AC.
gmܶ : ADB BDC ABC
{dYmZ H$maU
{gÕVm : ADB Am{U ABC
Mr VwbZm H$ê$Z
(i) ADB = ABC = 90° J¥hrV
(ii) BAD = CAB g‘mB©H$ H$moZ
A
B
D
C
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Similar Triangles 291
(iii) ABD = ACB {ÌkH$moUmÀ¶m {VÝhr H$moZm§Mr
~oarO 180° AgVo.
ADB ABC (1) g‘H$moZ {ÌH$moU
BDC Am{U ABC er VwbZm H$am.
(i) BDC = ABC = 90° J¥hrV
(ii) BCD = ACB g‘mB©H$ H$moZ
(iii) DBC = BAC {ÌkH$moUmÀ¶m {VÝhr H$moZm§Mr
~oarO 180° AgVo.
BDC ABC (2) g‘H$moZ {ÌH$moZ
AmVm Amåhr ADB BDC ABC
Cn{gÕm§V
à¶ËZ H$am : darb VrZ Cn{gÕm§VmgmR>r ˶m§Mo ì¶Ë¶mg ApñVËdmV AgyZ Vo g˶ AmhoV. à˶oH$mMr {gÕVm
JQ>m‘ܶo MMm© H$am Am{U ñdV§ÌnUo {bhm.
A
B
D
C
Cn{gÕm§V 1
ADB~ BDC [ g‘H$moZ]
AD DB ABAB BC AC
[ H$moH$mo H$gmoQ>r]
AB2 = AC.AD
JwUmoÎma ‘ܶ (G.M)Mr ì¶m»¶m AmR>dm.darb g‘rH$aUmdê$Z Amåhr Ago gm§Jy H$sAC Am{U AD Mm JwUmoÎma ‘ܶ AB Amho.
Cn{gÕm§V 2
BDC ~ ABC [ g‘H$moZ]
BD DC BCAB BC AC
[ H$moH$mo H$gmoQ>r]
BC2 = AC.DC
JwUmoÎma ‘ܶmÀ¶m ì¶m»¶oZwgma Amåhr Agogm§Jy H$s AC$Am{U DC Mm JwUmoÎma ‘ܶBC $Amho.
Cn{gÕm§V 3
ADB~ BDC [ g‘H$moZ]
AD DB ABBD DC BC [ H$moH$mo H$gmoQ>r]
BD2 = AD.DC
nwÝhm JwUmoÎma ‘ܶ (G.M)À¶m ì¶m»¶odê$ZAmåhr Ago gm§JVmo H$s BD hm AD.DC
Mm JwUmoÎma ‘ܶ Amho.
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292 UNIT-11
CXmhaU 1:- ABC ‘ܶo, BAC 90° AD hm {eamob§~. Oa
AB = 2 5, BD = 4 . Va BC Am{U AC H$mT>m.
$CH$b : AB2 = BC.BD [ Cn{gÕm§V]
22 5 BC.4
20BC
45 = BC
CD = BC – BD = 5 – 4 = 1
AC2 = BC.CD AC2 = 5 × 1 AC = 5
CXmhaU 2: ABC, ‘ܶo ABC 90° , Am{U BM hm {eamob§~ AmhoAm{U
Oa AM = 16MC Va {gÕ H$am AB = 4 BC
CH$b : AB2 = AC.AM [ Cn{gÕm§V]
AB2 = AC. 16 MC AB = 4 AC. MC
BC2 = AC.MC [ Cn{gÕm§V]
BC = AC. MC
na§Vw AB = 4 AC. MC
AB = 4 BC AC. MC BC
ñdmܶm¶ 11.5
1. ABC, ‘ܶo ABC = 90° BD AC
(a) BD = 8g|.‘r, AD = 4g|.‘r Va CD H$mT>m.
(b) AB = 5.7g|.‘r, BD = 3.8g|.‘r CD = 5.4g|.‘r Va BC H$mT>m.
(c) AB = 75g|.‘r, BC = 1‘r, AC = 1.25‘r Va BD H$mT>m.
2. ABC ‘ܶo BAC = 90° AD BC
BD = 4g|.‘r, DC = 5g|.‘r, Va x Am{U y H$mT>m.
3. PQR ‘ܶo PQR =90° QS PR
PQ = a, QR = b, RP = c Am{U QS = p, Va pc = ab ho XmIdm.
4. PQR ‘ܶo PQR =90° QD PR
PD = 4DR, Va PQ = 2QR ho {gÕ H$am.
A C
D
B
?
?
4
2 5
CM
B A
AD
B C
y
5 CB D4
x
A
DR
Q P
Q
p
P
bR
Sac
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Similar Triangles 293
5. ABC ‘ܶ ABC = 90° BM AC
(a) BM = x + 2, AM = x + 7, CM = x Va x H$mT>m.
(b) AM = 8x 2, MC = 2x 2 Va BM Am{U AB H$mT>m.
g‘ê$n {ÌH$moUm§Mo joÌ’$i
AmVmn¶ªV Amåhr g‘ê$n {ÌH$moUm§À¶m H$moZ Am{U ~mOy§À¶m ~m~VrV XmoZ ‘yb yV JwUY‘mªMm Aä¶mg Ho$bm
Amho. AmVm Vwåhr g‘ê$n {ÌH$moUm§À¶m joÌ’$imÀ¶m g§~§Ym{df¶r OmUyZ Koʶmg ’$ma CËgwH$ Agmb.
g§~§Y g‘OyZ KoʶmgmR>r Imbrb H¥$Vr H$am. g‘Om Imbrb à‘mUo ‘mno Agbobo g‘ê$n {ÌH$moU ABC
Am{U DEF AmhoV.
go§.‘rgo§.‘r
go§.‘r
go§.‘r
go§.‘r
go§.‘rgo§.‘r
go§.‘r
A
B C6
3.8
5
3.4
M50°40°
D
E F
1.9
2.5
31.
7
40° 50°
N
ABC Am{U DEF ‘ܶo
BAC EDF 90
ABC DEF 40
BCA EFD 50
ABC DEF
AB 5 2DE 2.5
BC 6 2EF 3
CA 3.8 2FD 1.9
AB BC CA 2DE EF FD
AmVm ˶m§À¶m joÌ’$im§À¶m JwUmoÎmamMm {dMma H$ê$.
BC
M
A
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294 UNIT-11
g‘Om AM BC Am{U DN EF.
AM = 3.4 g|.‘r., DN = 1.7 g|.‘r.
4noj
noj
12
12
ABC 63
3.41.7
AB BC CADE EF EDDEF
2 2 2
¶mMm AW© Agm H$s ABC Mo joÌ’$i DEF À¶m joÌ’$imÀ¶m Mma nQ> Amho.
XmoZ g‘ê$n H$mQ>H$moZ {ÌH$moUm§gmR>r Am{U XmoZ g‘ê$n {dembH$moZ {ÌH$moUm§gmR>r hr H¥$Vr nwÝhm H$am. Vw‘MoAZw‘mZ H$m¶ AmhoV? JQ>m‘ܶo MMm© H$am.
¶mMo Amåhr Imbrbà‘mUo gm‘mݶ {dYmZ H$ê$."g‘ê$n {ÌH$moUm§Mo joÌ’$i ˶m§À¶m g§JV ~mOydarb dJmªÀ¶m à‘mUmV AgVo."
à‘o¶ : "g‘ê$n {ÌH$moUm§Mo joÌ’$i ˶m§À¶m g§JV ~mOydarb dJmªÀ¶m à‘mUmV AgVo."A
B C
D
E FML
J¥hrV : ABC DEF
AB BC ACDE EF DF
gmܶ :Mo jo̒$i
Mo joÌ’$i
2
2ABC BCDEF EF
aMZm : AL BC Am{U DM EF H$mT>m.
{gÕVm : {dYmZ H$maU
ALB Am{U DME ¶m§Mr VwbZm H$am.
ABL = DEM [ J¥hrV]
ALB = DME = 900 [ aMZm]
ALB DME [ AA - H$gmoQ>r]
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Similar Triangles 295
AL ABDM DE
na§VwBC AB=EF DE [ J¥hrV]
AL BCDM EF
[ g§H«$‘U JwUY‘©]
Mo joÌ’$i
Mo joÌ’$i
2
2
1
1ABC B
EC ALF DMDEF
Mo joÌ’$i
Mo joÌ’$i
12
12
ABC BC AL BC ALDEF EF DM EF DM
AmVmMo joÌ’$i
Mo joÌ’$i( ABC) BC AL( DEF) EF DM
=BC ALEF DM
=BC BCEF EF
AL BCDM EF
=2
2
BCEF
Q>rn
AB BC AC= =DE EF DF ¶m J¥hrVH$mdê$Z
Mo joÌ’$iMo joÌ’$i
2 2 2
2 2 2ABC AB BC AC= = =DEF DE EF DF
ñnï>rH$aUmË‘H$ CXmhaUo
1. ABC ‘ܶo, XY || BC Am{U XY {ÌH$moUmg g‘mZ joÌ’$i AgUmè¶m XmoZ ^mJmV {d^mJVm§ Va .
BXAB H$mT>m.
J¥hrV : ABC ‘ܶo
A
B C
X Y
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296 UNIT-11
(i) XY || BC
(ii) ABC = 2 AXY
gmܶ :BXAB
{gÜXVm : ABC AXY [ XY || BC]
Mo joÌ’$i
Mo joÌ’$i
2
2
( ABC) AB( AXY) AX [ WoëgMm à‘eo¶]
2
2
2 AB1 AX
2 AB1 AX1 AX
AB2
1 AX1 1AB2
2 1 AB AXAB2
2 1 BXAB2
‘hËdmMo n[aUm‘ : 1. AX 1AB 2
2.XB 2 2AB 2
3.AX 1XB 2 1
2. "Oa XmoZ g‘ê$n {ÌH$moUm§Mo joÌ’$i g‘mZ Agob Va Vo EH$ê$n AgVmV." ho {gÕ H$am.
A
B C E
D
FSimilar triangles
g‘ê$n {ÌH$moU
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Similar Triangles 297
J¥hrV : ABC ~ DEF
Mo joÌ’$i ( ABC) = Mo joÌ’$i ( DEF)
gmܶ : ABC DEF
{gÕVm :Mo joÌ’$iMo joÌ’$i
2 2 2
2 2 2
( ABC) AB BC CA( DEF) DE EF FD [ à‘o¶]
2 2 2
2 2 2
AB BC CA1DE EF FD
[ J¥hrV dê$Z
joÌ’$i g‘mZ AgVo]
AB2 = DE2 AB = DEBC2 = EF2 BC = EFCA2 = FD2 CA = FD
ABC DEF [ SSS]
3. D, E Am{U F ho ABC À¶m ~mOy§Mo ‘ܶ AmhoV. P,Q Am{U R ho DEF À¶m ~mOy§Mo ‘ܶ q~Xÿ AmhoV‘ܶq~Xÿ§À¶m IwUm H$ê$Z ZdrZ {ÌH$moU ~Z{dʶmMr {H«$¶m AerM Mmby R>odm.V¶ma hmoUmè¶m {ÌH$moUm§À¶m joÌ’$im‘ܶo H$m¶ g§~§Y Amho? Vnmg H$am Am{U AZw‘mZ H$mT>m.Amåhr ¶mnyduM {gÕ Ho$bo Amho H$s,
ADF DBE CEF ABCA
B C
D
E
F
Q
P
R
Mo joÌ’$iMo joÌ’$i
2 2
22
4
ABC BC BC 4DEF DF BC
DEF =14
ABC
Mo joÌ’$iMo joÌ’$i
2 2
2 2ABC BC BC 16PQR QR BC
PQR =1
16 ABC
åhUyZ joÌ’$io hr1 11, ,4 16 .........
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298 UNIT-11
hr JwUmoÎma H«$‘mV (G.P) AgyZ r =14
OmUwZ ¿¶m ! (Know this)
g‘ê$n {ÌH$moUm§Mr joÌ’$io1. ˶m§À¶m g§JV ~mOydarb Mm¡agm§À¶m.2. ˶m§À¶m g§JV {eamob§~m§darb Mm¡agm§À¶m.3. ˶m§À¶m g§JV ‘ܶJmdarb Mm¡agm§À¶m.4. ˶m§À¶m g§JV n[a{ÌÁ¶m§darb Mm¡agm§À¶m.5. ˶m§À¶m g§JV H$moZ Xþ mOH$mdarb Mm¡agm§À¶m.6. ˶m§À¶m g§JV {ÌÁ¶m§darb Mm¡agm§À¶m
à‘mUmV AgVmV.
gyMZm : darb ghm {dYmZm§Mo ì¶Ë¶mg XoIrb bmJy nS>VmV.
ñdmܶm¶ 11.6
g‘ê$n {ÌH$moUmda AmYm[aV Cnà‘o¶.1. BC ¶m g‘mZ nm¶mda ABC Am{U BDC AmhoV.
{gÕ H$amMo joÌ’$iMo joÌ’$iABC AO
DODBC
2. ABC Am{U BDE ho XmoZ g‘ wO {ÌH$moU AmhoV.
BD = DC, Va ABC Am{U BDE À¶m joÌ’$im‘Yrb JwUmoÎmaH$mT>m.
3. XmoZ g‘{Û wO {ÌH$moUm§Mo {eamoH$moZ (vertical angles) g‘mZ AgyZ ˶m§À¶m joÌ’$im§Mo JwUmoÎma 9 : 16
Amho. ˶m§À¶m g§JV {eamob§~m§Mo JwUmoÎma H$mT>m.
4. XmoZ g‘ê$n {ÌH$moUm§Mo {eamob§~ AZwH«$‘o 3 g|.‘r Am{U 5 g|.‘r AmhoV. ˶m§À¶m joÌ’$im‘Yrb JwUmoÎma
H$mT>m.
5. g‘b§~ Mm¡H$moZ ABCD ‘ܶo
A
BC
D
O
A
B CD
E
60
60
6060
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Similar Triangles 299
AB || CD, AB = 2CD Am{U
( AOB) Mo joÌ’$i = 84 g|.‘r2, COD Mo joÌ’$i H$mT>m.
6. darb AmH¥$Vr‘ܶo Oa AB = 3CD Va AOB Am{U COD ¶m§À¶m joÌ’$im‘Yrb JwUmoÎma H$mT>m.
A B
CD
O
Similar Triangles
Similar Figures
Similar traingles
Criteria for similarityof triangles
A A Criteria Logical proof
Converse of A A criteria-SSS criteria
SAS Criteria
Theorem related toRight angled triangle
Areas of similartriangles Logical proof
Numerical problemsand riders
Corollary 1
Corollary 2
Corollary 3
Basic ProportionalityTheorem (BPT)
Converse of BPT
Numerical problemsand riders
g‘ê$n {ÌH$moU
g‘ê$n AmH¥$˶m
g‘ê$n {ÌH$moU
‘yb yV à‘mUmMm à‘o¶ (‘y.à.à) BPT
‘yb^yV à‘mUmÀ¶m‹ à‘o¶mÀ¶m ì¶Ë¶mg
Cn{gÕm§V 1
Cn{gÕm§V 2
Cn{gÕm§V 3
g§»¶mË‘H$ CXmhaUo Am{UCnà‘o¶H$mQ>H$moZ {ÌH$moUmer g§~§§§{YV
à‘o¶
VH©$ {gÕm§Vg‘ê$n {ÌH$moUm§MrjoÌnio
SAS H$gmoQ>r
AA H$gmoQ>r ì¶Ë¶mgSSS - H$gmoQ>r
AA H$gmoQ>r VH©$ {gÕm§V
{ÌH$moUm§À¶m g‘ê$nVoMrH$gmoQ>r
g§»¶mË‘H$ CXmhaUo Am{UCnà‘o¶
©
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300 UNIT-11
CÎmao
ñdmܶm¶ 11.2
A 2) BE = 10.5 g|.‘r, CE = 7.5 g|.‘r. 3) (i) 20 g|.‘r. (ii) 6 g|.‘r. (iii) x = 1
5) 6 g|.‘r. 6) AK = 12 g|.‘r, PB = 10 g|.‘r. 7) 8 ’y$Q> 8) 2 ’y$Q>
ñdmܶm¶ 11.3
A 1) 15 g|.‘r. 21g|.‘r. 2) 2.6 g|.‘r. ` 3) 1.6 ‘r.
ñdmܶm¶ 11.5
1) (a) 16 g|.‘r. (b) 6.6 g|.‘r. (c) 0.6 g|.‘r. 2) x =6 g|.‘r. y = 52 g|.‘r. 5) (a) 34
(b) 52 24 4x x
ñdmܶm¶ 11.6
2) 4:1 3) 3:4 4) 9:25 5) 21 g|.‘r2. 6) 9:1
********
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¶m KQ>H$m§‘wio Vw‘Mo ¶m‘ܶo gwb^rH$aU hmoVo
* nm¶W°Jmoag n«‘o¶.* nm¶W°JmoagÀ¶m à‘o¶mMm ì¶Ë¶mg* nm¶W°JmoagMr {ÌHo$* nm¶W°JmoagÀ¶m à‘o¶mMr {gÜXVm Am{U ˶mMm ì¶Ë¶mg.* nm¶W°Jmoag à‘o¶mda AmYmarV àíZ
Am{U Cnà‘o¶.
12
There is geometry in the humming ofthe strings, there is music in thespacing of spheres.
-Pythagoras
nm¶W°Jmoag à‘o¶Pythagorus Theorem
* nm`W°JmoagÀ`m à‘o¶mMo {dYmZ H$aUo
* VH©$ewÜX nÜXVrZo nm¶W°Jmoag à‘o¶ {gÜX H$aUo
* nm¶W°JmoagÀ¶m à‘o¶mÀ¶m ì¶Ë¶mgmMo ñnï>rH$aU.
* VH©$ewÜX nÜXVrZo nm¶W°Jmoag à‘o¶mMm ì¶Ë¶mg {gÜX
H$aUo.
* nm¶W°JmoagÀ¶m {ÌH$m§À¶m AWm©Mo ñnï>rH$aU.
* AZw‘m{ZH$ ¶w{º$dmX Am{U nm¶W°Jmoag à‘o¶ d Cn
à‘o¶mda AmYm[aV à‘o¶ Am{U ˶m§Mo ì¶Ë¶mg m§Mr {gÜXVm.
* nm¶W°Jmoag à‘o¶mda AmYm[aV dmñVd OrdZmdarb
CXmhaUm§Mo n¥W:H$aU H$aUo Am{U gmoS>{dUo.
nm¶W°Jmoag
(569-479 B.C, J«rg)
nm¶W°Jmoag WoëgMm {eî¶ hm H$Xm{MVH$mQ>H$moZ {ÌH$moUmdarb à‘o¶mMr Mm§Jbr‘m{hVr AgUmam, H$s Á¶mbm ˶mMo Zm§d{Xbo Amho. nXm§À¶m ‘m{hV Zgboë¶mì¶m»¶m ñnï> ì¶m»¶m, J¥hrVVËdo, VH©$ewÜXAZw‘mZ ¶m §À¶m ‘XVrZo ^ y{‘VrÀ¶mAä¶mgmMr VH©$ewÜX arVrZo àJVr H$aʶmg¶mZo ‘XV Ho$br. J{UV {dkmZ, g§JrV,Y‘© Am{U VËdkmZ, ¶m joÌmVrb ˶mMogm‘϶© AmOXoIrb MQ>H$Z bjmV ¶oVo.
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Pythagoras Theorem 302
Amåhr ¶mnydu {eH$bobo H$mQ>H$moZ {ÌH$moUmMo H$m§hr JwUY‘© AmR>dy.1. H$mQ>H$moZmÀ¶m {déÜX AgUmè¶m ~mOybm H$U© åhUVmV.2. H$mQ>H$moZ {ÌH$moUm‘ܶo, H$U© hr gdm©V bm§~ ~mOy AgVo.3. g‘{Û wO H$mQ>H$moZ {ÌH$moUm‘ܶo à˶oH$ bKwH$moZ 450 AgVmo.4.H$mQ>H$moZ {ÌH$moUmMo joÌ’$i ho H$mQ>H$moZ H$aUmè¶m ~mOy§À¶m
JwUmH$mamÀ¶ {Zå‘o AgVo.5.H$mQ>H$moZ {eamoq~XÿVyZ H$Um©da b§~ H$mT>ë¶mg Vmo {ÌH$moUmbm XmoZ g‘én
{ÌH$moUm‘ܶo {d^mJVmo Oo {Xboë¶m H$mQ>H$moZ {ÌH$moUmbm g‘én AgVmV.AmVm,Amåhr H$mQ>H$moZ{ÌH$moUm§À¶m ~m~VrV AmUIr EH$ A{Ve¶ ‘Zmoa§OH$ JwUY‘m©Mm Aä¶mg H$é.
JwUY‘© g‘OyZ KoʶmgmR>r, Imbrb H¥$Vr H$am.* AB = 4 g|.‘r. BC = 3 g|.‘r., AC = 5
g|.‘r. AgUmam ABC, aMm.* [ZarjU H$am H$s, ABC ~amo~a 90° AgVmo.* {VÝhr ~mOyda Mm¡ag aMm Am{U ˶m§Mo à˶oH$s 1
g|.‘r. ~mOy AgUmè¶m Mm¡agm‘ܶo {d^mJ H$am.AmVm {VÝhr ~mOyda AgUmè¶m bhmZ Mm¡agm§Mrg§»¶m ‘moOm. ˶m 9,16 Am{U 25 AmhoV. OaAmåhr9 Am{U 16 {‘i{dbo Va Amåhmbm 25{_iVo.{4g|.‘r., 6 g|.‘r. Am{U 10 g|.‘r.}, {5 g|.‘r.,12 g|.‘r, 13 g|.‘r} B˶mXr, ~mOy AgUmè¶m H$mQ>H$moZ{ÌH$moUm§gmR>r hr H¥$Vr nwÝhm H$am. ¶mdéZAmåhr H$m¶AZw‘mZ H$mT>Vmo? AmåhrAgm AZw‘mZ H$mT>Vmo H$s,""H$mQ>H$m oZ {ÌH$moUm‘ܶo, H$Um©darb Mm¡ag hm BVa XmoZ ~mOydarb Mm¡agm§À¶m ~oaOoBVH$mAgVm o''¶m {dYmZm‘wio H$mQ>H$moZ {ÌH$moUmÀ¶m ~mOydarb joÌ’$im‘ܶo
AgUmam g§~§Y {‘iVmo Á¶mbm nm¶W°Jmoagà‘o¶ åhUVmV, gw‘mao 500BC À¶m Xaå¶mZ hmoD$Z Joboë¶m J«rH$ J{UVVk nm¶W°JmoagÀ¶m Zm§dmdéZ ¶mbm nm¶W°Jmoag à‘o¶ AgoZm§d nS>bo. ¶m à‘o¶mMm Cn¶moJ J{UVmÀ¶m AZoH$ emIm‘ܶo Ho$bm AgyZ ˶mZr AZoH$ J{UVVkm§Mo bj AmH${f©V H$éZ KoVbo Am{U AmOAmnë¶mH$S>o ¶mgmR>r eoH$S>mo {d{dY nwamdo AmhoV. nm¶W°Jmoag à‘o¶mMo{dYmZ àm¶mo{JH$[a˶m Xþgè¶m ‘mJm©Zo {gÜX H$aVm ¶oVo. ho hoÝar no[aJb(1830) ¶m§Zr {Xbo. åhUyZ ¶mbm no[aJb {dÀN>oXZ Ago åhUVmV.
Imbr {Xboë¶m H¥$VrMm Aä¶mg H$am Am{U Vr JQ>m‘ܶo H$am.* AmH¥$VrV XmI{dë¶mà‘mUo nwÇ>>çmdaC ‘ܶo H$mQ>H$moZ H$aUmam
ABC, aMm.
3 cm
3 cm
3cm
3cm
4cm
4
4 cm
4 cm
cm
5 cm
m
5 cm 5cm
5c
A
B C
BC
P
EF
A
DG
5
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Pythagoras Theorem 303
A
B C
D
* AB, BC Am{U CA da Mm¡ag H$mT>m. ¶m Mm¡agm‘ܶo, AmH¥$VrVXmI{dë¶mà‘mUo Am{U Imbr {Xboë¶m nm¶è¶m à‘mUo aMZm H$am.
* H$mQ>H$moZ H$aUmè¶m ‘moR>çm BC ~mOydarb Mm¡agm‘ܶo P ‘ܶq~Xÿ {ZpíMV H$am.(Mm¡agmMo H$U© OmoSy>Zho {‘i{dVm ¶oVo)
* P ‘YyZ DE || AB Am{U FG DE .H$mT>m.* V¶ma hmoUmè¶m Mm¡H$moZm§Zm 1,2,3 Am{U 4, Ago H«$‘m§H$ Úm Am{U AC darb Mm¡agmbm 5 H«$‘m§H$ Úm
( AmH¥$VrMo {ZarjU H$am)* Mm¡H$moZ 1,2,3,4, Am{U 5.H$mnm.* H$U© AB.da H$mT>boë¶m Mm¡agmda H$mnboë¶m AmH¥$˶m Owidm (AmH¥$VrMo {ZarjU H$am)
H$mQ>H$m oZ {ÌH$m oUmÀ¶m ~mOy§À¶m dJm ªÀ¶m joÌ’$im{df¶r Amåhr H$m¶ {ZîH$f© H$mT>Vmo?
nm¶W°Jmoag à‘o¶H$mQ>H$moZ {ÌH$moUm‘ܶo, H$Um©darb Mm¡ag hm BVa XmoZ ~mOydarb Mm¡agm§À¶m ~oaOoBVH$m AgVmo.
J¥hrV : ABC ‘ܶo, ABC = 90°gmܶ : AB2 + BC2 = CA2
aMZm : BD AC. H$mT>m{gÜXVm : {dYmZ H$m aU
ABC Am{U ADB,Mr VwbZm H$amABC ADB 90 ( J¥hrV Am{U aMZm )
BAD g‘mB©H$
ABC ADB ( g‘H$moZ {ÌH$moU)
ABAD
=ACAB
( A A g‘énVm H$gmoQ>r )
AB2 = AC.AD .....(1)
ABC Am{U BDC, ¶m§Mr VwbZm H$amABC = BDC=900 ( J¥hrV Am{U aMZm )
ACB g‘mB©H$ Amho.
ABC BDC [ g_H$moZ {ÌH$moU]
BC ACDC BC
[ g‘énVm H$gmoQ>r] ( A A g‘énVm H$gmoQ>r )
BC2 = AC.DC .....(2) (1) Am{U (2) {‘idyZ Amåhmbm {‘iVo.
AB2 + BC2 = (AC. AD) + (AC. DC)AB2 + BC2 = AC (AD + DC)AB2 + BC2 = AC. AC = AC2 [ AD + DC = AC) AB2+ BC2 = AC2
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Pythagoras Theorem 304
‘m{hV Amho!~m¡ÜXm¶Z ¶m àmMrZ ^maVr¶ J{UVVkmZo 800 BC À¶m Xaå¶mZ V¶maHo$bobr gwwëd gyÌo ho 춺$ H$aVmV H$s Am¶VmMm H$U© Ë`mÀ` bm§~r Am{Uê§$XrMr doJir joÌ\$io ~Z{dVmV.
d2 = l2 + b2
¶m H$maUmgmR>r, hm à‘o¶ ""~moYm¶Z à‘o¶'' Agmhr C„oIbm OmVmo.
‘m{hV Amho AmO Amnë¶mH$S>o nm¶W°Jmoag à‘o¶mgmR>r {d{dY nwamdo AmhoV. Ago åhQ>bo OmVo H$s VoWo 300hÿZA{YH$ nwamdo AgyZ ˶mn¡H$s H$m§hr {ÌH$moU{‘Vr, gh {ZX}eH$ ^y{‘Vr, gXre B˶mXrda AmYm[aV AgyZ {gÜXHo$bo AmhoV.
˶mn¡H$s H$m§hr {‘i{dʶmMm à¶ËZ H$a Am{U JQ>m‘ܶo MMm© H$am.
ñnï>rH$aUmË‘H$ CXmhaUo
nm¶W°Jmoag à‘o¶mda AmYm[aV g§»¶mË‘H$ g‘ñ¶mCXmhaU 1:
H$mQ>H$moZ ABC‘ܶo, , AC = 17go.‘r. Am{U AB = 8go.‘r., BC H$mT>m.CH$b : ABC ‘ܶo, B= 90° {Xbo Amho
AC2 = AB2 + BC2 nm¶W°Jmoag à‘o¶]BC2 = AC2 - AB2
BC2 = 172 - 82
BC2 = 289 - 64 = 225BC = 15 g|.‘r.
CXmhaU 2 :ABC‘ܶo, ABC = 450, AM BC, AM = 4g|.‘r. Am{U BC = 7g|.‘ r. AC Mr bm §~ r
H$mT >m.CH$b : AMB‘ܶo,
AMBhm g‘{Û^wO H$mQ>H$moZ {ÌH$moU MA = MB = 4g|.‘r.MC = BC – MB = 7 – 4 = 3go§.‘r MC = 3cm
AMC‘ܶo, AC2= AM2 + MC2 [ nm¶W°Jmoag à‘o¶]AC2 = 42 + 32
AC2 = 16 + 9AC2 = 25AC= 5 g|.‘r.
b b
l
l
d
?
A
B M C
4cm
7cm
45°
go§.‘rgo§.‘
r
A
B C
178
?
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Pythagoras Theorem 305
CXmhaU 3 :
WXYZ ¶m Am¶Vm‘ܶo, XY + YZ = 17g|.‘r.Am{UXZ + YW = 26 go§.‘r. Am`VmMr bm §~r Am{U ê§$XrH$T> m.
CH$b : XZ + YW = 26 g|.‘r.
d1 + d2 = 26 g|.‘r.
2d = 26 g|.‘r. [ d1 = d2]
d = 13 g|.‘r.
XZ = YW = 13g|.‘r.
g‘Om bm§~r = XY = x g|.‘r._mZy é§Xr = XW = (17 – x)g|.‘r.
WXY ‘ܶo, WX2 + XY2 = WY2 [ nm¶W°Jmoag à‘o¶]
(17 – x)2 + x2 = 132
(289 – 34x + x2) + x2 = 169
(2x2 – 34x + 120 = 0) 2
x2 – 17x + 60 = 0
x2 – 12x – 5x + 60 = 0
x(x – 12) –5(x – 12) = 0
(x – 12)(x – 5) = 0
x – 12 = 0 or x – 5 = 0
x = 12 qH$dm x = 5
bm§~r = 12 g|.‘r., é§Xr = 5 g|.‘r.
CXmhaU 4 :6‘r C§MrÀ¶m Im §~mÀ¶m nm¶mnmgyZ 8‘r. A§Vamda AgUmam EH$ H$sQ>H$ Im§~mÀ¶m {XeoZ o
hihiy gaH$Vm o. H$m §hr A§Va gaH$ë¶mZ§Va ˶mMo {Xì¶mÀ¶m Im §~mÀ¶m ‘m϶mnmgyZMo A§Va ho VogaH$boë¶m A§VamBVHo$ AgVo Va Vo H$sQ>H$ {Xì¶mÀ¶m Im§~mÀ¶m nm¶mnmgyZ {H$Vr A§Vamda Amho ?[^mñH$amMm¶m ªÀ¶m brbmdVr]CH$b : H$sQ>H$ Am{U {Xì¶mÀ¶m Im§~mÀ¶m nm¶m‘Yrb A§Va = BD = 8 ‘r.{Xì¶mÀ¶m Im§~mMr C§Mr = AB = 6 ‘r.H$m§§hr A§Va gaH$ë¶mZ§Va, g‘Om H$sQ>H$ C, ¶oWo Amho.
g‘Om AC = CD = x ‘r. BC = (8 - x) ‘r.
X
W Z
Y
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Pythagoras Theorem 306
ABC ‘ܶo, B 90 AC2 = AB2+BC2 ( nm¶W°Jmoag à‘o¶ )
x2 = 62 + ( 8- x)2
2x = 36 + 64 - 16x + 2x
16x = 100
x =100 6.2516
BC = 8- x
BC = (8-6.25) = 1.75 mH$sQ>H$ {Xì¶mÀ¶m Im§~mÀ¶m nm¶Ï¶mnmgyZ 1.75 ‘r. Xÿa Amho.Q>rn : Amåhr BC = X, ‘mZë¶mg CD = AC = (8 – x)
nm`W°Jmoag à_o`mdarb Cnà_o`.CXmhaU 5: {Xboë¶m AmH¥$Vr‘ܶo, AD BC, {gÜX H$am H$s AB2 + CD2 = BD2 + AC2
CH$b : ADC ‘ܶo, ADC 90Ð = °
AC2 = AD2 + CD2 (nm¶W°Jmoag à‘o¶mdê$Z ) .......(1)
ADB ‘ܶo, ADB 90Ð = ° AB2 = AD2 + BD2 ( nm¶W°Jmoag à‘o¶) .......(2)
( nm¶W°Jmoag à‘o¶)
(2) ‘YyZ (1), dOm H$éZ Amåhmbm {‘iVo,
AB2 – AC2 = AD 2 + BD2 - AD 2 - CD2
AB2 – AC2 = BD2 - CD2
AB2 + CD2 = BD2 + AC2
CXmhaU 6 :ABD‘ܶo, BD da C hm Agm q~Xÿ Amho H$s, BC : CD = 1 : 2 Am{U ABC hm g‘^wO
{ÌH$moU Amho Va {gÜX H$am H$s AD2 = 7AC2.CH$b. J¥hrV : ABD ‘ܶo, BC : CD = 1 : 2
ABC ‘ܶo, AB = BC = CA
gmܶ : AD2 = 7AC2
aMZm: AE BC H$mT>m.
{gÜXVm: ABC ‘ܶo
BE = EC =2a
Am{U
A
B
6 =x
=
8-x xC D
A
B
C
D
.
A
B C DE
a a
2a60°60°
32
a
2a
2a
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Pythagoras Theorem 307
AE =3
2a
ADE, ‘ܶo, AED 90 [ aMZm]
AD2 = AE2 + ED2 [ nm¶W°Jmoag à_o ]
AD2 =2 23 2
2 2a aa
AD2 =223 5
4 2a a
AD2 =2 23 25
4 4a a
AD2 =2 23 25
4a a
AD2 =228
4a
AD2 = 7a2
AD2 = 7 AC2
ñdmܶm¶ 12.1
A nm¶W°Jmoag à‘o¶mdarb g§»¶mË‘H$ CXmhaUo1. H$mQ>H$moZ {ÌH$moUmÀ¶m H$mQ>H$moZ H$aUmè¶m ~mOy 5 g|.‘r. Am{U 12 g|.‘r. AmhoV. {ÌH$moUmMm H$U© H$mT>m.2. 12 g|.‘r. ~mOy Agboë¶m Mm¡agmÀ¶m H$Um©Mr bm§~r H$mT>m.3. Am¶VmH¥$Vr H«$sS>m§JUmÀ¶m H$Um©Mr bm§~r 125 _r.Am{U EH$m ~mOwMr bm§~r 75 _r. Amho Xwgè`m ~mOwMr
bm§~r H$mT>m.
4. LAW‘ܶo, LAW 90Ð = ° , LNA 90Ð = °
Am{U LW = 26 g|.‘r.,LN = 6g|.‘r.
Am{U AN = 8 g|.‘r. WA Mr bm§~r H$mT>m.
5. 6 ‘rQ>a é§Xr Agboë¶m XadmOmbm
2 ‘rQ>a C§MrMr H$‘mZ Amho. H$‘mZrMr {ÌÁ¶m H$mT>m.
W A
L
26 cm N8cm
6cm
h = 2m
6m
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Pythagoras Theorem 308
6. 9 ’y$Q> C§MrÀ¶m Im§~mdarb ‘moa, Im§~mnmgyZ 27 ’y$Q> A§Vamdarb gmnmbm ~KyZ, H$s Omo Im§~mÀ¶m VimerAgUmè¶m ~rimH$S>o ¶oV Amho ˶mbm nH$S>ʶmgmR>r CÈ>mU H$aVmo Oa XmoKm§Mm doJ g‘mZ Agë¶mgIm§~mnmgyZ {H$Vr A§Vamda XmoKo EH$Ì ¶oVrb?
B nm¶W°JmoagÀ`m à_o¶mdma AmYmarV Cnà_ o`.
1. MGN ‘ܶo, MP GN. Oa MG = a EH$H$, MN = b EH$H$, GP =c
EH$H$ Am{U PN = d EH$H$, Va
{gÜX H$am (a + b)(a – b) = (c + d)(c – d).
2. ABC‘ܶo, ABC = 900, BD AC. Oa AB = 'c' EH$H$,BC = 'a' EH$H$, BD = 'p' EH$H$ , CA = 'b' EH$H$.
{gÜX H$am 2 2 2
1 1 1a c p .
3. g‘ wO {ÌH$moUmMr C§Mr Am{U joÌ’$imMo gyÌ aMm.nm¶W°Jm oagMr {ÌHo$
Vwåhr H$mQ>H$moZ {ÌH$moUmÀ¶m VrZ ~mOy§À¶m ‘mnZm‘ܶo EH$ {deof nÜXVrMm g§~§Y Amhoho {eH$bm AmhmV.
Oa VrZ Aem, g§»¶m, H$s Á¶m H$mQ>H$moZ {ÌH$moUmÀ¶m {VÝhr ~mOy§Mr ‘mno Agboë¶m YZg§»¶m AgVrb Va ˶mZm nm¶W°JmoagMr {ÌHo$ åhUVmV.
˶mn¡H$s H$m§htMr ¶mXr Imbrb V³Ë¶m‘ܶo {Xbr Amho ˶m§Mm Aä¶mg H$am.A B
3, 4, 5 6, 8, 105, 12, 13 15, 36, 397, 24, 25 14, 48, 5011, 60, 61 44, 240, 244
A ñV§ mVrb à˶oH$ nm¶W°JmoagÀ¶m {ÌH$mMr VwbZm B ñV§ mVrb g§JV {ÌH$m~amo~a H$am.Amåhr Agm {ZîH$f© H$mT>Vmo H$s, Oa (x, y, z) ho nm¶W°JmoagMo {ÌH$ Agob Va (kx, ky, kz) ho XoIrb nm¶W°JmoagMo{ÌH$ Amho OoWo k N.
OmUyZ ¿¶m!
Imbrb gm‘mݶ gyÌ dmnéZ nm¶W°JmoagMr {ÌHo$ H$mT>Vm ¶oVmV.
Z¡g{J©H$ g§»¶ogmR>r : 2n, (n2 – 1), (n2 + 1) ¶oWo 'n' hr g‘ qH$dm {df‘ AgVo.
{df‘ Z¡g{J©H$ g§»¶m§gmR>r : n, 21 ( 1),2
n 21 ( 1),2
n ¶oWo n {df‘ AgyZ
OoWo n N.
darb gm‘mݶ gyÌmdéZ, 'n' bm qH$‘V XodyZ ‘moR>çm g§»¶oZo nm¶W°JmoagMr {ÌHo$ CËnÞ H$aVm ¶oVmV.
M
G NP
a
d
b
c
a
bpc
A
B C
D
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Pythagoras Theorem 309
nm¶W°Jmoag à‘o¶mMm ì¶Ë¶mg (Converse of Pythagorus Theorem)
AmVm AmnU nm¶W°Jmoag à‘o¶mMm ì¶Ë¶mg {eHy$. ¶m gmR>r, XmoZ CXmhaUm§Mm {dMma H$am.
AQ> Aer Amho : ""Oa {ÌH$moUmÀ¶m gdm©V ‘moR>çm ~mOydarb Mm¡ag BVa XmoZ ~mOydarb Mm¡agm§À¶m
~oaOoBVH$m Agob Va ˶m Xm oZ ~mOy‘Yrb H$moZ H$mQ>H$moZ AgVmo.
hm nm¶W°Jmoag à‘o¶mMm ì¶Ë¶mg Amho. ¶mMm gd© àW‘ ¶wp³bS>Zo C„oI Ho$bm Am{U {gÜX Ho$bm.
AmVm nm¶W°Jmoag à‘o¶mMm ì¶Ë¶mg VH©$ewÜX nÜXVrZo {gÜX H$é.
CXmhaU 2
P
Q R5 cm
4cm
4.3 cm
• g‘Om PQR hm QR = 5go§.‘r., PQ = 4g|.‘r.Am{U PR = 4.3 g|.‘r.AgUma Xwgam {ÌH$moU Amho
• {VÝhr ~mOydarb Mm¡agm§Mr H$ënZm H$am Am{U˶m§Mo joÌ’$i H$mT>m.
• ¶oWo gdm©V bm§~ ~mOy QR Amho Am{U ˶mMrbm§~r 5 g|.‘r. Amho.QR ¶m gdm©V ‘moR>çm~mOydarb Mm¡agmMo joÌ’$i 25 Mm¡. g|.‘r. Amho.
• BVa XmoZ ~mOy PQ Am{U PR darb (16 + 18.49)
Mm¡.g|.‘r.= 34.49 Mm¡. g|.‘r. Agob Or gdm©Vbm§~ ~mOy QR darb Mm¡agmÀ¶m joÌ’$imBVH$s Zmhr.
• AmVm QPRÐ ‘moOm, Omo gdm©V bm§~ ~mOyQR, bm {déÜX Amho Vwåhmbm Ago {XgyZ ¶oB©bH$s QPR 90° Mm Zmhr.
• åhUyZ, PQR hm H$mQ>H$moZ {ÌH$moU Zmhr.
CXmhaU 1
A
B C5 cm
4 cm
3cm
• g‘Om ABC hm BC = 5 g|.‘r. AB =4go§.‘r Am{U AC =3 go§.‘r AgUmam {ÌH$moU Amho.• {VÝhr ~mOydarb Mm¡agm§Mr H$ënZm H$am Am{U
˶m§Mo joÌ’$i H$mT>m.• ¶oWo gdm©V bm§~ ~mOy BC Am{U ˶mMr bm§~r 5
g|.‘r. Amho BC ¶m gdm©V ‘moR>çm ~mOydarbMm¡agmMo joÌ’$i 25 Mm¡. g|.‘r. Amho
• BVa XmoZ ~mOy AB Am{U AC darb Mm¡agm§Mr~oarO (16 + 9) Mm¡.g|.‘r. Agob Vr XoIrb 25Mm¡, go._r.Amho.
• AmVm BACÐ ‘moOm, Omo gdm©V bm§~ ~mOy BC
bm {déÜX Amho. Vwåhmbm ABCÐ = 90°
{‘iob.• åhUyZ, ABC hm A {eamoq~Xyer H$mQ>H$moZ H$aUma
H$mQ>H$moZ {ÌH$moZ Amho• åhUyZ {ÌH$moU H$mQ>H$moZ AgÊ`mgmR>r H$moUVr
_yb yV AQ> Amho darb CXmhaUmVrb XmoZ{ÌH$moUm§À`m ~mOydarb joÌ\$im§Mr VwbZm H$amAm{U Amdí`H$ AQ> g_OyZ KoÊ`mMm à`ËZH$am.
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Pythagoras Theorem 310
nm¶W°JmoagÀ¶m à‘o¶mMm ì¶Ë¶mg"Oa {ÌH$moUmÀ¶m gdm©V ‘moR>çm ~mOydarb Mm¡ag hm BVa XmoZ ~mOydarb Mm¡agm§À¶m ~oaOo BVH$m Agob. Va ˶mXmoZ ~mOy‘Yrb H$moZ H$mQ>H$moZ AgVmo".
A
B CD
J¥hrV : ABC ‘ܶo, AC2 = AB2 + BC2
gmܶ : ABC = 90°Ð
aMZm : B ‘ܶo AB b§~ H$mT>m ˶mda 'D' q~Xÿ Agm {ZdS>m H$s DB = BC. 'A'Am{U D OmoS>m.
{dYmZ H$m aU
{gÜXVm : ABD‘ܶo,
ABD = 90° ( aMZm)
AD2 = AB2 + BD2 (nm¶W°Jmoag à‘o¶)
na§Vw ABC ‘ܶo,
AC2 = AB2 + BC2 ( J¥hrV)
AD2 = AC2
AD = AC
ABD Am{U ABC ¶m§Mr VwbZm H$am.
AD = AC ( {gÜX)
BD = BC ( aMZm)
AB hr g‘mB©H$
ABD ABC ( SSS)
ABD = ABC (PCT)
na§Vw ABD + ABC = 180° ( aofr¶ OmoS>r)
ABD = ABC = 90°
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Pythagoras Theorem 311
ho OmUyZ ¿¶m : {ÌH$moUmMm {VÝhr ~mOyÀ¶m Mm¡agmdarb g§~§YmMm Aä¶mg H$am.
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1 : Imbrb ‘mno H$mQ>H$moZ {ÌH$moUmÀ¶m ~mOy Xe©{dVmV H$m¶ ho nS>VmiyZ nhm. (a) 6, 8, 10
CH$b. : 6, 8, 10 ¶m ~mOy AmhoV.
Ago ‘mZy H$s ~mOydarb Mm¡agm§À¶m joÌ’$im§Mr ~oarO : 62, 82, 102
i.e., 36, 64, 100
Amåhr Ago {ZarajU H$aVmo H$s, {ÌH$moUmÀ¶m gdm©V ‘moR>çm ~mOydarb Mm¡ag hm BVa XmoZ ~mOydarbMm¡agm§À¶m ~oaOoBVH$m Amho. : 36 + 64 = 100 62 + 82 = 102
nm¶W°Jmoag à‘o¶mÀ¶m ì¶Ë¶mgmdéZ, ˶m XmoZ bhmZ ~mOy‘ܶo H$mQ>H$moZ AgbmM nm{hOo.
{ZîH$f© : 6, 8 Am{U 10 ~mOy H$mQ>H$moZ {ÌH$moU ~Z{dVmV Á¶m‘ܶo H$U© 10 EH$H$ Am{U 6 Am{U 8EH$H$ Agboë¶m ~mOy‘Yrb H$moZ H$mQ>H$moZ AgVmo.
Q>rn: {Xboë¶m ~mOy§À¶m ‘mnmgmR>r à˶jmV ÌH$moUmMr aMZm Z H$aVm, nm¶W°Jmoag à‘o¶mMm ì¶Ë¶mg dmnéZAmVm Ago gm§JUo e³¶ Amho H$s, ˶m ~mOy H$mQ>H$moZ {ÌH$moUmÀ¶m AmhoV ho Xe©{dbo OmVo.
(b)4, 5, 6
~mOy : 4, 5, 6~mOydarb Mm¡agm§Mo joÌ’$i åhUOoM :42, 52, 62
åhUOo, : 16, 25, 36XmoZ bhmZ ~mOydarb Mm¡agm§À¶m joÌ’$im§Mr ~oarO
: 16 + 25 = 41
42 + 52 62
A
B C a
bc
ABC ‘ܶo, ABCABC = 90°AC2 = AB2 + BC2
b2 = c2 + a2
Oa b2 = c2 + a2
Va ABC 90°=
A
B C
bc
a*
ABC ‘ܶo,ABCABC < 90°
AC2< AB2 + BC2 ì¶Ë¶mgb2 < c2 + a2
Oa b2 < c2 + a2
Va ABC < 90°Ð
*
A
B C a
bc
ABC ‘ܶo,ABCABC < 90°AC2 > AB2 + BC2
b2 > c2 + a2
Oa b2 > c2 + a2
Va ABC 90°
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Pythagoras Theorem 312
Amåhr {ZarjU H$aVmo H$s {ÌH$moUmÀ¶m gdm©V ‘moR>çm ~mOydarb Mm¡ag hm BVa XmoZ ~mOydarb Mm¡agm§À¶m~oaOoBVH$m Zmhr.
nm¶W°Jmoag à‘o¶mÀ¶m ì¶Ë¶mgmdéZ, ¶m XmoZ ~mOy‘ܶo hmoUmam H$moZ H$mQ>H$moZ Zmhr.
åhUyZ, 4, 5, Am{U 6 ¶m H$mQ>H$moZ {ÌH$moUmÀ¶m ~mOy hmoUma ZmhrV..
CXmhaU 2 : Mm¡H$moZ ABCD, ABC 90 Am{U
AD2 = (AB2 + BC2 + CD2). Va {gÜX H$am : H$s ACD 90
A
B C
D
{gÜXVm : ABC‘ܶo, ABC < 90°Ð ABC 90= ° [ J¥hrV]
AC2 = AB2 + BC2 [ nm¶W°Jmoag à‘o¶]
na§Vw AD2 = (AB2 + BC2)+CD2 [ J¥hrV]
AD2 = AC2 + CD2 [ J¥hrVmdéZ AB2 + BC2 = AC2]
ACDÐ = 90° [ nm¶W°Jmoag à‘o¶mMm ì¶Ë¶mg]
ñdmܶm¶ 12.2
1. nS>VmiyZ nhm H$s Imbrb ‘mno H$mQ>H$moZ {ÌH$moUmÀ¶m ~mOy Xe©{dVmV.
(i) 1, 2, 3 (ii) 2, 3, 5
(iii) 36 12 6, , (iv)m2 – n2, 2mn, m2 + n2
2. ABC‘ܶo, a + b = 18 EH$H$, b + c = 25 EH$H$ Am{U c + a = 17EH$H$ Amho. ABC hm H$moU˶m àH$maMm {ÌH$moU Amho ? H$maUo Úm.
3. ABC ‘ܶo, CD AB, CA = 2AD Am{U BD = 3AD,
{gÜX H$am H$s BCA 90
4. 'A' q~XÿnmgyZ QR Mo H$‘rVH$‘r A§Va 12 g|.‘r.
Amho. 'A' nmgyZ 'Q' Am{U 'R' ho AZwH«$‘o 15 g|.‘r.
Am{U 20 g|.‘r AgyZ AP ~mOyÀ¶m {déÜX AmhoV. {gÜX H$am
QAR 90Ð = °
A
B CA
Q P R
15 c
m
20 cm
12c m
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Pythagoras Theorem 313
5. g‘[Û wO ABC ‘ܶo,
(i) AB = AC (ii) BC = 18 go§.‘r.
(iii) AD BC (iv) AD = 12 g|.‘r.
(v)BC hr 'E' n¶ªV dmT>{dbr.
(vi) AE = 20 g|.‘r.Va
{gÜX H$am H$s BAE 90Ð = °
6. Mm¡H$moZ ABCD ‘ܶo
ADC 90Ð = ° , AB = 9g|.‘r., BC = AD = 6 g|.‘r.
Am{U CD = 3g|.‘r.Va, {gÜX H$am H$s ACB 90Ð =
7. ABCD hm Am¶V Amho. 'P' hm ~mhoaÀ¶m ~mOyg H$moUVmhrq~Xÿ Agm Amho H$s
PA2 + PC2 = BA2 + BD2. Va {gÜX H$am H$s APC 90Ð = °
A
B CD E18 cm
20 cm
12cm
A
B C
D
P
B
CD
9 cm
3 cm
6cm
6 cm
nm¶W°Jmoag à‘o¶
nm¶W°Jmoag à‘o¶ OmVrà{Vkm nm¶W°Jmoag à‘o¶mMm ì¶Ë¶mg nm¶W°JmoagMr{ÌHo$
VH$m©Ë‘H$ {gÕVm {gÕm§V
ñdmܶm¶ 11.11. 13 g§o.‘r 2. 12 2 g§o.‘r 3. 100 ‘r 4. 24 g§o.‘r
5. 3. 25 g§o.‘r 6. 12 ’y$Q>
********
CÎmao
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Vwåhmbm ¶m KQ>H$m‘wio ¶m§Mo gwb^rH$aU hmoVo
* À¶m ~m~VrV (g§X^m©V) H$mQ>H$moZ {ÌH$moUmMr {déÕ,
gb¾ Am{U H$U© AmoiIUo.
* H$mQ>H$moZ {ÌH$moUmÀ¶m ~mOy§er g§~§{YV ghm JwUmoÎmam§Mr
ì¶m»¶m H$aUo.
* {ÌH$moU{‘VrMr ghm JwUmoÎmao AmoiIUo.
* {Xboë¶m H$mQ>H$m oZ {ÌH$moUmÀ¶m, {ÌH$moU{‘VrÀ¶m
JwU§moÎmam§Mr qH$‘V H$mT>Uo.
* 0°, 30°, 45°, 60° Am{U 90° ¶m H$m§hr AmXe©
H$moZm§À¶m, {ÌH$moU{‘VrÀ¶m H$moZm§À¶m qH$‘Vr H$mT>Uo.
* {Xboë¶m {ÌH$moU{‘VrÀ¶m JwUmoÎmamMm H$moQ>rH$moZ H$mT>Uo.
* sin2 + cos2 = 1 gyÌ aMU o
* {Xboë¶m KQ>ZoVrb Cƒ nmVirVrb H$moZ Am{U {Zƒ
nmVirVrb H$moZ AmoiIUo.
* C§Mr Am{U A§Va ¶m§À¶mer g§~§{YV CXmhaUo gmoS>{dUo.
13 Trigonometry
* H$mQ>H$moZ {ÌH$moUmÀ¶m ~mOy
* H$mQ>H$moZ {ÌH$moUmÀ¶m ~mOy §Mr ghmJwUmoÎmao
* {ÌH$moU{‘VrMr AmoiI
* AmXe© H$moZm§À¶m, {ÌH$moU{‘VrÀ¶mJwUmoÎmamÀ¶m qH$‘Vr.
* {ÌH$moU{‘Vr¶ g‘rH$aUo
* C§Mr Am{U A§Vamdarb g‘ñ¶m
{hßn°aH$g
Xþgao eV‘mZ BC ‘Yrb J«rH$ J{UV
Vk {hßn°aH$g ¶mZm {ÌH$moU{‘VrMm
{Z‘m©Vm Ago g‘Obo OmVo.
{ÌH$moU{‘Vr eãXmMm AW© {ÌH$moUmMo
‘mnZ ¶mMo lo¶ ~mgWmobm o‘Z
{n{Q>ñH$g (1561-1613) ¶mZm
{‘iVo.
There is perhaps nothing which so occupies themiddle position of mathematics as trigonometry.
-J.F. Herbart
{ÌH$moU{‘Vr
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Trigonometry 315
Vwåhmbm AZoH$ doim AmíM¶© dmQ>bo Agob H$s J{UVr {hoeo~mZo àM§S> (‘moR>çm) C§Mr Am{U A§Va H$go
H$mT>bo OmVo. Amnë¶m g^modVmbMr H$m§hr {R>H$mUo Imbr {Xbr AmhoV, OoWo Aem {heo~mMr JaO Amho.
Aem gd© g‘ê$n KQ>Zm‘ܶo, C§Mr Am{U A§Va J{UVr V§ÌmMm Cn¶moJ H$ê$Z H$mT>Vm ¶oVmV, Á¶m§Mm Aä¶mg
J{UVmÀ¶m Á¶m emIoV Ho$bm OmVmo ˶mbm "{ÌH$moU{‘Vr" åhUVmV. {ÌH$moU{‘Vr hm eãX Tri (VrZ) gon(~mOy) Am{U metron (‘mnZ) ¶m J«rH$ eãXm§nmgyZ {‘i{dbm Amho.
åhUyZ {ÌH$moU{‘Vr åhUOo VrZ ~mOy ‘moOUo qH$dm {ÌH$moUmÀ¶m VrZ ~mOy ‘moOUo hm {ÌH$moUmÀ¶m ~mOy
Am{U H$moZm‘Yrb g§~§YmMm Aä¶mg Amho.
åhUyZ {ÌH$moU{‘Vr hr {ÌH$moUm{df¶r gd© H$m§hr Amho.
‘§{XamMr C§Mr Hw$Vw~{‘ZmaMr C§Mr
ZXrÀ¶m nmÌmMr ê$§Xr ‘Zmoam Am{U B‘maV ¶m‘Yrb A§Va
{na°{‘S>Mr C§Mrnd©VmMr C§Mr
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316 UNIT-13
P
Q R75° 35°
{ÌH$moU{‘Vrdarb ¶mnydu ‘m{hV Agboë¶m H$m‘mMr Zm|X B{Oá Am{U ~°{~bm°Z ‘ܶo hmoVr. àmMrZH$mimVrb J«rH$ IJmobemók {ÌH$moU{‘VrMm Cn¶moJ M§ÐmMo n¥ÏdrnmgyZMo A§Va H$mT>ʶmg H$arV AgV.
AmO XoIrb {ÌH$moU{‘Vrdarb gd© gmYmaU H$ënZm§da AmYmarV Am¡Úmo{JH$ H$bm{dkmZmÀ¶m Ñï>rZo nwT>oAgboë¶m nÕVr ^m¡{VH$ {dkmZ, {dÚwV gma»¶m doJdoJù¶m A{^¶m§{ÌH$s emIm, O{‘ZrMr ‘moOUr, {eënemó,Zm¡H$mZ¶Zemó, IJmobemó Am{U gm‘mݶ {dkmZ ¶m‘ܶo A˶§V Cn¶wº$ AgVmV.
{ÌH$moU{‘Vrdarb gd© g§H$ënZm H$mQ>H$moZ {ÌH$moUmda AmYm[aV AmhoV. H$mQ>H$moZ {ÌH$moUmÀ¶m ~mOy§Mrbm§~r Am{U H$moZm§Mo ‘mn ¶m§À¶mer g§~§{YV AmhoV. H$m§hr {R>H$mUr OoWo {ÌH$moUm§Mo kmZ H$er ‘hËdmMr ^y{‘H$m~OmdVo ho Imbr XmI{dbo Amho.
Á¶m AWu {ÌH$moU{‘Vrbm H$mQ>H$moZ {ÌH$moUmÀ¶m H$moZ Am{U ~mOy~amo~a ~aoM H$mhr H$amd¶mMo Amho, VoìhmàW‘ Amdí¶H$ ‘ybVËdo AmR>dy.
g‘Om H$mQ>H$moZ {ÌH$moU Amho. ~mOy Am{U ˶m§À¶m Zmdm§Mo {Z[ajU H$am.
nm¶W°JmoagÀ¶m à‘o¶mV {Xì¶mà‘mUo H$mQ>H$moZ {ÌH$moUmVrb~mOy§À¶m g§~§Ym{df¶r Vwåhr ¶mnydu {eH$bm AmhmV. AmVm AmnUAer H$m§hr CXmhaUo KoD$ H$s OooWo {ÌH$moUmÀ¶m ~mOy qH$dm H$moZm§Mm{hemo~ Ho$bm Amho.
CXmhaU 1 : ABC ‘ܶo Oa B = 900, AC = 5 g|.‘r, Am{U AB = 3g|.‘r Va BC Mr bm§~r {H$Vr?AC2 = AB2 + BC2 (nm¶W°JmoagÀ¶m à‘o¶mdê$Z)BC2 = AC2 – AB2
= 52 – 32 = 25 – 9 = 16
BC = 16 = 4 g|.‘r
CXmhaU 2 : PQR ‘ܶo P Mo ‘mn {H$Vr?P + Q + R = 180° (H$moZm§À¶m ~oaOoMm JwUY‘©)
P = 180° – ( Q + R)= 180° – (75° + 35°) = 180° – 110° = 70°
P = 700
A
B C
HypotenuseLegs or armsof right angleH$mQ>H$moZ {ÌH$moUmMonm¶ qH$dm ~mhÿ
H$U©
5 cm
3cm
B C
A
g|.‘rg|.‘r
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Trigonometry 317
AmVm Imbrb CXmhaUm§Mo {ZarjU H$am.
CXmhaU 3 : DEF ‘ܶo DE H$mT>m. CXmhaU 4 : XYZ ‘ܶo X H$mT>m.D
E F9 cm
4 cm
X 10 cm
7 cm
Y
80°
Z
nm¶W°JmoagMm à‘o¶ qH$dm H$moZm§À¶m ~oaOoMm JwUY‘© dmnê$Z Amåhmbm ~mOyMr bm§~r qH$dm H$moZmMo ‘mnH$mT>Vm ¶oB©b H$m?
Vw‘Mo dJ©{‘Ì Am{U {ejH$m§~amo~a dJm©V MMm© H$am.
ho CKS> Amho H$s nm¶W°JmoagMm à‘o¶ qH$dm {ÌH$moUmÀ¶m H$moZm§À¶m ~oaOoMm JwUY‘© dmnê$Z Amåhr darbCXmhaUo gmoS>dy eH$V Zm§hr. Aer CXmhaUo H$er gmoS>{dVmV?
{ÌH$moU{‘Vr dmnê$Z ~mOy Am{U H$moZ H$mT>Uo e³¶ Amho.
{ÌH$moU{‘Vr åhUOo {ÌH$moU gmoS>{dUo Am{U gmoS>{dUo åhUOo {ÌH$moUmÀ¶m ~mOy Am{U H$moZ H$mT>Uo.
{ÌH$moU{‘VrMr ‘yb^yVo (Basics of Trigonometry)AmVm AmnU {ÌH$moU{‘VrÀ¶m ‘yb yVm{df¶r {eHy$. {ÌH$moU{‘VrMr ‘yb yVo
hm ’$º$ H$mQ>H$moZ {ÌH$moUm§er g§~§{YV AmhoV.
EH$ H$moZ 90° AgyZ ˶mÀ¶m {dê$Õ AgUmar ~mOy H$U© AgUmè¶mABC Mm {dMma H$am.
Ago g‘Om H$s H$mQ>H$moZ gmoSy>Z BVa H$moZmZm Amåhr IwUm Ho$ë¶m Amåhr EH$Va BAC qH$dm ACBAem IwUm H$aVmo, H$s Oo Zoh‘r bKwH$moZ AgVmV. IyU Ho$bobm H$moZ ' ' Zo Xe©{dbm OmVmo. (J«rH$ eãX, WrQ>mAgm dmMVmV)
Voìhm H$moZmer g§~§{YV AgUmè¶m ~mOyZm H$m¶ åhUVmV?
Imbrb AmH¥$˶m§Mo {ZarjU H$am Am{U ~mOyZm Zm§do H$er {Xbr AmhoV ¶mMm Aä¶mg H$am.A
B C
Hypotenuse
Adja
cent
Opposite
A
B C
Hypotenuse
Opp
osite
Adjacent
À¶m {dê$Õ AgUmè¶m ~mOybm {dê$Õ ~mOy Am{U Xþgè¶m ~mOybm gb¾ ~mOy åhUVmV.
Oa A= Va BC hr {dê$Õ ~mOy Am{U AB hr gb¾ ~mOy Amho.
Oa C= Va AB hr {dê$Õ ~mOy Am{U BC hr gb¾ ~mOy Amho.
' ' H$moZmMo ‘mn "A§e" {H§$dm "H$moZ ‘moOʶmMo EH$H$" ¶mZo Xe©{dbo OmVo.
A
B C
Hypotenuse
g|.‘rg|.‘r
g|.‘r g|.‘r
H$U©
H$U©
gb¾
{dê$Õ
{dê$Õ gb¾
H$U©
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318 UNIT-13
6
4
3
2
ho OmUm:
1 EH$H$ bm§~rÀ¶m H§$gmZo 1 EH$H$ {ÌÁ¶oÀ¶m dVw©imV H|$Ðmer A§mVarV Ho$bobm H$moZ
‘moOʶmMo EH$H$ 1C Zoo Xe©{dVmV 1C = 1800
¶oWo H$m§hr CXmhaUo AmhoV.
A§e H$moZ ‘moOʶmMo EH$H$
30°
45°
60°
90°
180°
360°
àH$aU 10 ‘ܶo Amåhr g‘ê$n {ÌH$moUmÀ¶m AAA H$gmoQ>r{df¶r Aä¶mg Ho$bm Amho. ¶mMm Cn¶moJ H$ê$ZAmåhr {ÌH$moU{‘VrMr ‘yb yVo {dH${gV H$ê$.
Imbrb CXmhaUm§Mm Aä¶mg H$am.
ABC Am{U DEF ho g‘H$moZ {ÌH$moU AmhoV. åhUyZ ˶m§À¶m g§JV ~mOy à‘mUmV AmhoV.
5cm
2cm
4cm
A
B C
2.5cm1cm
2cm
D
E F
ABC ~ DEF, ABDE = BC CA
EF FD=
AmVm EH$m doir H$moU˶mhr XmoZ JwUmoÎmam§Mm {dMma H$am.
ABDE =
BCEF
hr JwUmoÎmao Aerhr {b{hVm ¶oVmV.
11
1
1800
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Trigonometry 319
ABBC =
DEEF [Oaif than
a c a bb d c d
é ù= =ê úë ûVaif than
a c a bb d c d
é ù= =ê úë û]
{Xboë¶m AmH¥$˶m‘ܶo
ABBC = 2cm 1
4cm 2= Am{U
DE 1EF 2
=ABBC = DE 1
EF 2=
¶mMmM AW© ABC, ‘ܶo BC hr AB À¶m XþßnQ> Am{U EF hr DE À¶m XþßnQ> Amho.
Amåhr Agm AZw‘mZ H$mTy> H$s ABC À¶m ~mOy AB Am{U BC er AgUmam H$moUVmhr g§~§Y
DEF À¶m g§JV ~mOy DE Am{U EF er gmaImM AgVmo. Oa Vo XmoÝhr {ÌH$moU g‘ê$n AgVrb VaABBC = 2cm 1
4cm 2= Am{U
DE 1EF 2
=ABBC = DE 1
EF 2=
hm {ZîH$f© Xþgè¶m g§JV ~mOy§À¶m OmoS>çm§À¶m ~m~VrV {dñVmarV H$ê$.
åhUyZABBC =
DE 1EF 2
= =BCCA =
EF 1FD 2 =
22.5
CAAB =
FD 2.5DE 1
=
g‘Om, H$mQ>H$moZ {ÌH$moUm§À¶m ~m~VrV ¶m ¶moOZoMm {dñVma H$ê$. H$mQ>H$moZ {ÌH$moUm‘ܶo Aem XmoZ {deofKQ>Zm AmhoV.
KQ>Zm (i): 45° – 45°– 90° H$mQ>H$moZ {ÌH$moU qH$dm g‘{Û^wO H$mQ>H$moZ {ÌH$moU
g‘Om XmoZ g‘H$moZ g‘{Û wO H$mQ>H$moZ {ÌH$moU AmhoV.ABC ~ DEF
ABBC = DE 1
EF 1= H$mQ>H$moZ H$aUmè¶m
~mOy g‘mZ AgVmV.
BCCA
= EFFD =
12 H$U© hm ~mOy§À¶m
12 nQ> AgVmo.
ACAB = FD 2
DE 1= H$U© hm ~mOy§À¶m 2 nQ> AgVmo.
KQ>Zm (ii): 30°, 60°, 90° qH$dm H$mQ>H$moZ {ÌH$moU
g‘Om {Xboë¶m ‘mnm§Mo ABC Am{U DEF AmhoV.
A
B C
D
E F2
2 4
1
32 3
A
B C
D
E F
1 2 3 6
3 33
ABC ~ DEF ABC ~ DEF
F2
22 2
45°
45°
A
B C1
1 245°
45°
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320 UNIT-13
ABBC = DE
3EF
=ABBC =
DE 1EF 3
=
AB hr Zoh‘r BC À¶m 3 nQ> AgVo. BC hm Zoh‘r AB À¶m 3 nQ> AgVmo.BCCA =
EF 1FD 2
=BCCA = EF 3
FD 2=
CA (H$U©) Zoh‘r BC À¶m XþßnQ> AgVmo. CA (H$U©) BC À¶m XþßnQ> AgyZ ˶mbm 3 Zo ^mJVm oCA FD 2AB DE 3
= = CA FD 2AB DE 1
= =
CA (H$U©) hm Zoh‘r AB À¶m XþßnQ> CA (H$U©) Zoh‘r AB À¶m XþßnQ> AgVmo
AgyZ ˶mbm 3 Zo ^mJVmodarb CXmhaUmdê$Z Amåhr Agm {ZîH$f© H$mT>Vmo H$s
"H$mQ>H$moZ {ÌH$moUm‘ܶo, {Xboë¶m bKwH$moZmgmR>r H$moU˶mhr XmoZ ~mOy‘Yrb JwUmoÎma Zoh‘r pñWa AgVo."åhUyZ ¶mnwT>o JwUmoÎma {b{hʶmgmR>r XmoZ g‘ê$n H$mQ>H$moZ {ÌH$moUmEodOr EH$mM H$mQ>H$moZ {ÌH$moZmMm
{dMma H$ê$.{ÌH$moU{‘VrMr JwUmoÎmao : (Trignometric ratios)
g‘Om EH$ H$mQ>H$moZ {ÌH$moU Amho Ago ‘mZy Am{U ˶m§À¶m bKwH$moZm§À¶m g§X^m©V ˶m§À¶m ~mOy§Mr e³¶{VVH$s JwUmoÎma {bhÿ.
AB AB BC, ,
AC BC ACAC BC AC
, ,AB AB BC
{ÌH$moUmbm VrZ ~mOy AmhoV. JwUmoÎma (fraction) {b{hVmZm A§e VrZ àH$ma Am{U N>oX XmoZ àH$ma{b{hVm ¶oVmo. XmoÝhr {‘iyZ 3 × 2 = 6 àH$mao {b{hVm ¶oVo. åhUyZ {ÌH$moUmÀ¶m ~mOy dmnê$Z Amnë¶mH$S>o ghmdJdoJir JwUmoÎma AmhoV.
{ÌH$moU{‘Vr‘ܶo, à˶oH$ ghm JwUmoÎmamZm Zm§d {Xbo Amho.ghm ‘yb^yV {ÌH$moU{‘VrMr JwUmoÎma o {eH$ʶmgmR>r Imbrb V³Ë¶mMm Aä¶mg H$am.
JwUmoÎma JwUmoÎmamMo {ÌH$moU{‘VrVrb Zm§d g§{já ê$nABAC = {dê$Õ
H$U©H$moZmMm gmB©Z gmB©Z (sin
gb½ZH$U©
BCAC = H$moZmMm H$mogmB©Z H$m°g (cos
gb½Z{dê$ÕB
BA
C = H$moZmMm Q>°ZO|Q> Q>°Z (tanH$U©{dê$Õ
ABAC = H$moZmMm H$mogoH§$Q> H$mogoH$ (cosec
BCAC = gb½Z
H$U© H$moZmMm goH§$Q> goH$ (sec
gb½Z{dê$ÕB
BA
C = H$moZmMm H$moQ>°ZO|Q> H$m°Q> (cot
A
B C
Opp
osit
e Hypotenuse
Adjacent
{dê$Õ
gb¾
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Trigonometry 321
¶m ghm {ÌH$moU{‘VrÀ¶m JwUmoÎmamVrb g§~§Y hm "H$mQ>H$moZ {ÌH$moUm‘ܶo Oa bKwH$moZ {Xbm Agob VaH$moU˶mhr XmoZ ~mOy‘Yrb JwUmoÎma H$mT>Vm ¶oVo. CbQ> AWr©, Oa XmoZ ~mOy‘Yrb JwUmoÎma {Xbo Agob Va, H$moZH$mT>Vm ¶oVmo. "AAA g‘ê$nVm H$gmoQ>r‘wio ho gd© e³¶ Amho".
ho ‘m{hV H$ê$Z ¿¶m : gmB©Z (Sine) ¶m H$ënZoMm Cn¶moJ àW‘ Am¶©^Å> (500AD) ¶m§À¶m Am¶© Q>r¶m‘ ¶m H$m‘m‘ܶo 500 AD ‘ܶo {XgyZ Ambm. na§VwAm¶©^Å>Zo AY©-OrdogmR>r AYu Á¶m eãXmMm Cn¶moJ Ho$bm, Aä¶mg H«$‘mVg§{jáê$nmV Vmo Á¶m qH$dm Ordm Agm {b{hVmV. Am¶© Å>r¶m‘Mo Aao{~H$ ‘ܶoê$nm§Va H$aVmZm Ordm eãX VgmM am{hbm. nwT>o ˶mMo "gm¶Zg' ‘ܶo ê$nm§Va Pmbo,¶mMm b°{Q>Z‘ܶo dH«$ Agm AW© hmoVmo. ES>‘§S> Jw§Q>a (1581-1626) ¶mIJmobemómÀ¶m B§J«Or àmܶmnH$mZo gm¶Zg eãX gmB©Z(Sine) ¶m g§{já ê$nm§VaH$ê$Z àW‘ dmnabm. H$mogmB©Z Am{U "Q>°ZO|Q>' eãXm§Mm CJ‘ Iyn Ceram Pmbm.H$moQ>rH$moZmMm gmB©Z ‘moOʶmMr JaO ^mgë¶mda H$mogmB©ZMo H$m¶© gwê$ Pmbo. Am¶© Å>Zo ¶mbm H$moQ>rÁ¶m AgoåhQ>bo. ES>‘§S> Jw§Q>a ~amo~a H$mogm¶ZgMm CJ‘ Pmbm. 1674 ‘ܶo ga OmoZg ‘ya ¶m Xþgè¶m B§p½be J{UVVkmZo "H$m°g''cos' ¶m g§{já {MÝhmMm àW‘ Cn¶moJ Ho$bm.
Q>rn :1. H$moZmÀ¶m gmB©ZMo g§{já ê$n gmB©Z (sine Ago Amho, ¶mMm AW© ¶m bKwH$moZmÀ¶m g§X^m©V
{dê$ÜX ~mOy Am{U H$U© ¶m§Mo JwUmoÎma. ¶mbm gmB©Z Am{U ¶m§Mm JwUmH$ma Ago ‘mZVm ¶oV Zm§hr .
BVa {ÌH$moU{‘VrÀ¶m JwUmoÎmam§À¶m ~m~VrV XoIrb AgoM AgVo.
sine Ago Amho H$s-˶mbm {H$§‘V Amho.
sine ho H$mhr Zmhr - ¶mbm H$mhr AW© Zmhr.
gmB©Z Ago H$m§hrVar Amho H$s Á¶mbm qH$‘V Amho. ’$º$ gmB©Zbm H$m§hrM AW© ZgVmo.
2. {ÌH$moU{‘VrMr JwUmÎmao {ÌH$moUmÀ¶m AmH$mamda Adb§~yZ ZgyZ Vr ’$º$ ¶m bKwH$moZmÀ¶m qH$‘Vrda
Adb§~yZ AgVmV.
¶oWo {Xboë¶m {ÌH$moUm§À¶m g§X^m©V
AmnU AmUIr H$m§hr CXmhaUo KoD$Z {ÌH$moU{‘VrMr JwUmoÎmao {bhÿ.
A
B C
A
B C
A
B C30° 30° 30°
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322 UNIT-13
RQ
P
3
4
5
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1: g‘Om H$mQ>H$moZ {ÌH$moU ABC ‘ܶo 90ABCÐ = °
CH$b : ¶oWo CAB hm bKwH$moZ Amho. H$moZ A À¶m g§X^m©V ~mOy§À¶m pñWVrMo {Z[ajU H$am.
- BC hr H$moZ A Mr {dê$Õ ~mOy Amho.
- AB hr H$moZ A À¶m g§X^m©V g§b¾ ~mOy Amho.
- AC hm H$mQ>H$moZ {ÌH$moU ABC Mm H$U© Amho.
H$mQ>H$moZ {ÌH$moU ABC Mm H$moZ AÀ¶m {ÌH$moU{‘VrMm JwUmoÎmam§Mr ì¶m»¶m Imbrbà‘mUo Amho.
H$mQ>H$moZ {ÌH$moU ABC Mm H$moZ AÀ¶m {ÌH$moU{‘VrMm JwUmoÎmam§Mr ì¶m»¶m Imbrbà‘mUo Amho.
Sin A =BCAC
=H$moZ Mr {dê$ÜX ~mOyA
H$U© H$U©BCA
AA=
H$moZ Mr g§b½Z ~mOy
Tan A =B
BC
A=
H$moZ Mr {dê$ÜX ~mOyA
H$moZ Mr g§b½Z ~mOyA Cosec A = AH$moZ Mr {dê$ÜX ~mOy C
H$U©B
CA=
Sec A =H$U©
H$moZ Mr g§b½Z ~mOy BC
AA=
A CH$moZ Mr g§b½Z ~mOy
H$moZ Mr {dê$ÜX ~mOyB
BA
C=A
A
AmVm AmnU H$mQ>H$moZ {ÌH$moUm‘Yrb C bKwH$moZmgmR>r {ÌH$moU{‘VrÀ¶m JwUmoÎmamMr ì¶m»¶m ñnï> H$ê$
90ABCÐ = °
{ZarjU H$am H$s H$moZ A À¶m OmJr H$moZ 'C' ‘mZë¶mg ~mOy§Mr pñWVr ~XbVo.
Sin C =ABAC Cos C =
BCAC Tan C =
ABBC
Cosec = ACAB
Sec C =ACBC Cot C =
BCAB
CXmhaU 2: PQR gmR>r {ÌH$moU{‘VrMr JwUmoÎmao {bhm.
CH$b : AmH¥$Vr‘ܶo,
H$U© = 5 EH$H$, {dê$Õ = 3 EH$H$, g§b¾ = 4 EH$H$.
sin =H$U©
35
={dê$ÜX cosecH$U©{dê$ÜX
53
=
cos =H$U©
g§b½Z 45
= sec =gb½ZH$U© 5
4=
tan =gb½Z{dê$ÜX 3
4= cot =
gb½Z{dê$ÜX
43
=
A
B C
Hypotenuse
OppositeSide
Adj
acen
t sid
e
{dê$Õ ~mOy
gb¾
~mOy
{dê$Õ ~mOy
H$U©A
B C g§b½Z ~mOy{dê$ÜX
~mOy
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Trigonometry 323
XmhaU 3: XYZ gmR>r {ÌH$moU{‘VrMr JwUmoÎmao {bhm.
CH$b : {Xbobo XY = 15, YZ = 8, XZ = ?
XZ2 = XY2 + YZ2 (>nm¶W°Jmoag à‘o¶mdê$Z)= 152 + 82 = 225 + 64 = 289
XZ = 289 = 17.
sin =1517 cos =
817 tan =
158
cosec = 1715
sec =178 cot = 8
15
CXmhaU 4: sin A = 45 , A hm bKwH$moZ Amho.
2 tan A + 3 sec A + 4 sec A . cosec A Mr qH$‘V H$mT>m.
CH$b : {Xbobo sin A =H$U©
{dê$ÜX 45
=
ABC ‘ܶo AC2= AB2 + BC2 (nm¶W°Jmoag à‘o¶mdê$Z) BA2 = AC2 – AB2 = 52 – 42 = 25 – 16 = 9
BA = 9 = 3
åhUyZ tan A= gb½Z{dê$ÜX 4
3= sec A =
gb½ZH$U© 5
3= cosec A =
H$U©{dê$ÜX
54
=
2 tan A + 3 sec A + 4 sec A . cosec A ‘ܶo qH$‘Vr KmbyZ
= 3 3 3 44 5 5 52 3 4) ) ) )( ( ( (+ +
= 8 255
3 3+ + = 8 15 25 48
163 3
+ += =
2 tan A + 3 sec A + 4 sec A. cosec A = 16
ì¶ñV g§~§Y (ì¶wËH«$‘ g§~§Y) (Reciprocal Relation)g‘Om PQR ‘ܶo PQR = 900
Amåhmbm ‘m{hV Amho sin P =H$U©
{dê$ÜX QRPR
=
ZY
X
15
8
AB
C
4 5
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324 UNIT-13
2 1
1 12 12 2
2 1
1 12 12 2
2 1
1 12 12 2
sin P, Mm ì¶ñV H$mT>m åhUOoM 1 1 PRQRsinP QRPR
= =
na§VwH$U©{dê$ÜX
PRcosec P
QR= =
qH$dm1 1
sinP cosec P =cosec P sinP
=
åhUyZ sin P Am{U cosec P EH$‘oH$mZm ì¶ñV AmhoV.
¶mà‘mUo Amåhr BVa {ÌH$moU{‘VrÀ¶m JwUmoÎmam‘Yrb g§~§Y 춺$ H$ê$ eH$Vmo.
cos P =gb½Z
H$U©PQPR
= gb½ZH$U©1 1 PR
secPPQcosP PQPR
= = = =
1 1cosP or sec P
secP cosP\ = =
tan P =gb½Z
{dê$ÜXPQ
QR=
gb½Z
{dê$ÜX
1 1 PQcotP
PQtanP QRPR1 1tanP or cotP
cotP tanP
ì¶ñV g§~§YmMr ¶mXr Imbr {Xbr Amho.
sin A = 1cosec A
cos A = 1sec A
tan A = 1cot A
cosec A = 1sin A
sec A = 1cos A
cot A = 1tan A
AmR>dU H$am.
Imbr XmI{dë¶mà‘mUo eãXm§À¶m AmÚmjamZr ~ZUmè¶m eãXm§Mr AmR>dU H$ê$Z {ÌH$moU{‘VrMoJ wUm oÎma ghOnUo AmR>dVmV.
SOH CAH TOA
S O H Sin {déÕ OppositeH$U© Hypotenuse
C A H Cos g§b¾ Adjacent H$U© Hypotenuse
T O A Tan {dê$Õ Opposite g§b¾ Adjacent
darb VrZ JwUmoÎmam§À¶m ì¶ñVm‘wio AZwH«$‘o cosec , Sec Am{U cot {‘iVo.
RQ
P
Ad j
Opp.
HypH$U©
g§b¾
{déÕ
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Trigonometry 325
{ÌH$moU{‘VrÀ¶m JwUmoÎmam‘Yrb g§~§Y : (Relation between the trigonometric ratios) :
g‘Om ABC ‘ܶo B 90
gb½Z{dê$ÜX
BCsinA BCAC tanAABcos A AB
AC
sin Atan Acos A
1 1 cos Acot A = sinAtan A sinA
cos A
cos Acot Asin A
{Xboë¶m JwUmoÎmamÀ¶m nXmV {ÌH$moU{‘VrMr JwUmoÎmao 춺$ H$aUo :
AmVm Vwåhr {ÌH$moU{‘VrÀ¶m ghm JwUmoÎmam{df¶r n[a{MV AmhmV. Aem n[apñWVr‘ܶo EH$ ‘hËdmMmàý CX^dVmo.
Oa Amåhmbm H$moUVohr EH$ JwUmoÎma ‘m{hV Agob Va Amåhr Xþgar JwUmoÎmaoH$mTy> eH$Vmo?
g‘Om ABC. Sin A = BC K 1AC 3K 3
AmVm BVa {ÌH$moU{‘VrÀ¶m JwUmoÎmam§À¶m qH$‘Vr H$mTy>.
Oa sin A =13
, ¶mMm AW©BC 1AC 3
¶mMm AW© ~mOy BC Am{U AC Mr bm§~r 1 : 3 JwUmoÎmamV Amho.åhUyZ Oa BC ~amo~a K Agob Va AC ~amo~a 3K AgVo, OoWo K hr H$moUVrhr YZ g§»¶m AgVo.
BVa JwUmoÎmao {ZpíMV H$aʶmgmR>r Amåhmbm AB ¶m {Vgè¶m ~mOyÀ¶m bm§~rMr JaO Amho.
ABC ‘ܶo ABC = 900
AB2 = AC2 – BC2
= (3K)2 – K2 = 9K2 – K2 = 8K2 = 22 2K
AB = 22 2 2 2K K
cos A = AB 2 2K 2 2AC 3K 3
Am{U tan A =BC K 1AB 2 2K 2 2
cosec A = AC 3K3
BC KAm{U sec A =
AC 3K 3AB 2 2K 2 2
cot A = AB 2 2K2 2
BC K
CB
A
Hypotenuse
Opposite side
Adj
acen
tg§b
¾ ~m
Oy
H$U©
{déÕ ~mOy
A B
C
K3K
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326 UNIT-13
ñnï>rH$aUmËa‘H$ CXmhaUo
CXmhaU 1: Oa sin = 5.
13BVa gd© {ÌH$moU{‘VrÀ¶m JwUmoÎmam §À¶m qH$‘Vr {bhm.
CH$b :sin =Opp 5Hyp 13
ABC ‘ܶo, B 90 , C
AC2 = AB2 + BC2 (nm¶W°JmoagÀ¶m à‘o¶mdê$Z)BC2 = AC2 – AB2 = 132 – 52 = 169 – 25 = 144
BC = 144 = 12
cos =gb½Z
H$U©
1213 tan = gb½Z
{dê$ÜX125
cosec =H$U©{dê$ÜX
135
sec =gb½Z
H$U© 1312
cot =gb½Z{dê$ÜX
125
CXmhaU 2: Oa cos = 2425 Va {ÌH$moU{‘VrÀ¶m JwUmoÎmam§À¶m qH$‘Vr H$mT>m.
CH$b : ABC ‘ܶo B 90 , C
AB2 = AC2 – BC2 (nm¶W°JmoagÀ¶m à‘o¶mdê$Z)
x2 = 252 – 242 = 625 – 576 = 49
x = 49 = 7 AB = 7
AmVm Amåhr Imbrbà‘mUo {ÌH$moU{‘VrMr JwUmoÎmao {bhÿ eH$Vmo.
sin =H$U©
{dê$ÜX 725
cos =gb½ZH$U©
2425 tan =
gb½Z{dê$ÜX 7
24
cosec =H$U©
{dê$ÜX
257 sec =
gb½ZH$U© 25
24 cot =
gb½Z
{dê$ÜX
247
CXmhaU 3 : ABC ‘ܶo, AD BC Am{U BAD =
Oa AC= 20 g|.‘r, CD = 16 g|.‘r, Am{U BD = 5 g|.‘r, Va sin + cos Mr qH$‘V HmT>m.
CH$b : ADC ‘ܶo, ADC = 900
AD2 + DC2 = AC2
AD2 +162 = 202
CB
A
5 13
x
XB
A
25
24
x
H$U©
{dê$ÜX
257
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Trigonometry 327
AD2 = 202 162 = 400 256 =144
AD = 144 = 12 g|.‘r
AmVm ADB ‘ܶo, ADB = 900
AD2 + BD2 = 122 + 52 = AB2 = 144 + 25 = 169
AB = 169 = 13 g|.‘r
Sin BD 5 AD 12and cos
AB 13 AB 13
Sin 5 12 17cos13 13 13
CXmhaU 4 : {gÕ H$am H$s cos . cosec = cot
CH$b : g‘Om {Xboë¶m g‘rH$aUmMr S>mdr ~mOy (LHS)
cos . cosec = cos .1
sin1cosec
sin
=cossin
= cotcos
cotsin
= RHS cos . cosec = cot
CXmhaU 5: H$mQ>H$moZ {ÌH$moU ABC ‘ܶo, B hm H$mQ>H$moZ Amho.
Oa tan A=1, Va 2 sin A cos A =1 ho nS>VmiyZ nmhm.
CH$b : ABC ‘ܶo, ABC=900 tan A =BCAB
Á¶mAWu tan A = 1 ({Xbobo) BCAB
= 1 BC = AB
g‘Om AB = BC = k, OoW o k hr g‘g§»¶m Amho.
AmVm AC2 = AB2 +BC2 AC = 2 2AB +BC = 2 2k +k
AC = K 2
Sin A =BC K 1AC K 2 2 , Cos A =
AB K 1AC K 2 2
2 Sin A CosA =1 12 12 2
2 Sin A CosA = 1
A
5 cm 16 cm
20 cm
B CD
CB
A
H$U©
{dê$ÜX
257
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328 UNIT-13
(i) (ii) (iii)
CXmhaU 6: ABCD hm Agm g‘^wO {ÌH$moU Amho H$s Á¶mMm H$U© AC hm ~mOy CD er
H$m oZ H $ aV m o, O oW o cos = 23
. Oa PD=4 g |.‘ r Va g‘^ yO Mm ¡H $ m oZ mMr ~mO y Am{U H $U © H$ mT > m .
CH$b : Amnë¶mbm ‘m{hV Amho H$s g‘ wO Mm¡H$moZmMo H$U© EH$‘oH$m§Zm H$mQ>H$moZmV Xþ mJVmV.
DP = PB Am{U AP = PC
DPC ‘ܶo, DPC = 900 Cos =PC 2CD 3
PC = 2k Am{U CD = 3K
na§Vw, CD2 = PD2 +CP2 (3k)2 = 42+ (2k)2
9k2 = 16 + 4k2
5k2 = 16 qH$dm k2 =165
k =45
CD = 3k = 3 × 45 =
125 g|.‘r Am{U PC = 2k = 2 × 4
5 =85 g|.‘r
BD = 2PD = 2×4 = 8 g|.‘r Am{U AC = 2PC = 2 × 85 =
165 g|.‘r
g‘ wO Mm¡H$moZmMr à˶oH$ ~mOy =12
5 g|.‘r, H$U© BD = 8 g|.‘r Am{U H$U© AC =16
5 g|.‘r.
ñdmܶm¶ 13.1
I. Imbrb CXmhaU sin Am{U cos H$mT>m.
25
7
24 25
20
15 26
24
10
II. Imbrb qH$‘Vr H$mT>m.
1. Oa sin x =35
, cosec x =
2. Oa cos x =2425 , sec x =
3. Oa tan x =724 cot x =
D
A
P
B
C
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Trigonometry 329
4. Oa cosec x = 1525 , sin x =
5. Oa sin A =35
Am{U cos A =45
Va, tan A =
6. Oa cot A =8
15Am{U sin A =
1517
Va, cos A =
III. gmoS>dm :
1. tan A =34
, {Xbo AgVm sin A Am{U cos A Mr qH§$‘V H$mT>m.
2. cot =2021 , {Xbo AgVm cos Am{U cosec emoYm.
3. tan A = 724, {Xbo AgVm H$moZ A À¶m {ÌH$moU{‘VrMr BVa JwUmoÎmao H$mT>m.
4. Oa 2 sin = 3 , Va, cos , tan Am{U cot + cosec H$mT>m.
5. Oa 3 tan =1, Va, sin , cos Am{U cot H$mT>m.
6. Oa sec x = 2, Va sin x, tan x Am{U cot x Am{U cot x + cosec x H$mT>m.
7. Oa 4 sin A - 3 cos A = 0, Va sin A, cos A Am{U sec A, cosec A H$mT>m.
8. Oa 13 sin A = 5 Am{U A hm bKwH$moZ Agob Va5sin A 2cos A
tan A Mr qH$‘V H$mT>m.
9. Oa cos = 513
Am{U hm bKwH$moZ Agob Va5 tan 12cot5 tan 12cot Mr qH$‘V H$mT>m.
10. Oa 13 cos 5 = 0, Vasin cossin cos
H$mT>m.
à‘m{UV H$moZm§À¶m {ÌH$moU{‘VrMr JwUmoÎmao [Trigonometric ratios of Standard angles]
¶m àH$aUm‘ܶo AmVmn¶ªV Amåhr H$mQ>H$moZ {ÌH$moUmÀ¶m bKwH$moZm§À¶m {ÌH$moU{‘VrÀ¶m JwUmoÎmam{df¶rMMm© Ho$br. {ÌH$moUm‘ܶo 90° Mm H$mQ>H$moZ Am{U 90° nojm bhmZ AgUmam bKwH$moZ AgVmo. bKwH$moZmMo ‘mn90° nojm bhmZ Am{U 0° nojm ‘moR>o Ago H$moUVohr AgVo. na§Vw AZoH$Xm Amåhr 30°, 45° Am{U 60° hoà‘m{UV H$moZ aMZogmR>r dmnaVmo. g‘Om AmVm ¶m H$moZm§À¶m Am{U 0° gmR>r XoIrb {ÌH$moU{‘VrMr JwUmoÎma H$mTy>.
(1) 45° À¶m {ÌH$moU{‘VrMr JwUmoÎmao
g‘Om {ÌH$moU ABC g‘{Û wO H$mQ>H$moZ {ÌH$moU Amho.
OoWo B 90 . Oa Amåhr C 45 , KoVbm Va A XoIrb 45° AgVmo.
AB = BC ( g‘mZ H$moZmg‘moarb {dê$Õ ~mOy)
g‘Om AB = BC = 1 EH$H$ CB
A
45°
2
1
1
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330 UNIT-13
A
B CD
30°
60°
2
22
1 1
90°
3
A
B CD
30°
60°
AC2 = AB2 + BC2 (nm¶W°JmoagÀ¶m à‘o¶mdê$Z)AC2 = 12 + 12 = 1 + 1 = 2
AC = 2 EH$H$
AmVm H$moZ C À¶m g§X^m©V åhUOoM C 45 , {ÌH$moU{‘VrMr JwUmoÎmao
sin 45° =AB 1AC 2 cos 45° =
BC 1AC 2 tan 45° =
AB 11
BC 1
cosec 45° =AC 2
2AB 1
sec 45° =AC 2
2BC 1
cot 45° =BC 1
1AB 1
2) 30° Am{U 60° À¶m {ÌH$moU{‘VrMr JwUmoÎmao
Oar {ÌH$moU{‘VrÀ¶m JwUmoÎmam§Mm Aä¶mg ’$º$ H$mQ>H$moZ {ÌH$moUm§À¶m g§X^m©V(~m~VrV) Ho$bm OmVmo Var H$moU˶mhr àH$maÀ¶m {ÌH$moUm‘ܶo {eamob§~ H$mTy>Z ˶mMrCn¶mo{OVm H$aVm ¶oVo. ¶m H$ënZoMm Cn¶moJ 30° Am{U 60° À¶m {ÌH$moU{‘VrMr JwUmoÎmaoH$mT>ʶmg hmoVmo.
g‘Om {ÌH$moU ABC g‘ wO Amho.Á¶m AWu gd© H$moZ g‘mZ AgVmV, Amåhmbm {‘iVo A B C 60åhUyZ AB = BC = CAg‘Om A ‘YyZ BC da AD b§~ H$mT>bm
ABD ACD (EH$ê$nVoM RHS J¥hrVH$) BD = DC
BAD = CAD
Á¶m AWu BAC 60 , Amåhmbm {‘iVo, BAD = CAD = 300
AmVm, {ZarjU H$am H$s, ABD hm H$mQ>H$moZ {ÌH$moU Á¶m‘ܶo
ADB 90 , BAD 30 Am{U ABD 60
g‘Om nwÝhm EH$Xm ABC g‘ wO {ÌH$moU
{ÌH$moU{‘VrMr JwUmoÎmao H$mT>ʶmgmR>r {ÌH$moU ABC À¶m ~mOy§Mr bm§~rAmåhmbm ‘m{hV AgUo JaOoMo Amho.
g‘Om, AB = BC = CA = 2 EH$H$ ‘mZy
ABD ‘ܶo, AB = 2 EH$H$, BD = 1 EH$H$
Á¶mAWu ADB 90 , nm¶W°JmoagÀ¶m à‘o¶mdê$Z,AB2 = AD2 + BD2
22 = AD2 + 12
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Trigonometry 331
AD2 = 4 – 1 = 3 AD = 3
i) 300 À¶m {ÌH$m oU{‘VrMr JwUm oÎmao
sin 30° =H$U©
{dê$ÜX BD 1AB 2
cos 30° =gb½Z
H$U©
AD 3AB 2
tan 30° =H$U©
{dê$ÜX BD 1AD 3
cosec 30° =H$U©{dê$ÜX
AB 2BD sec30°=
gb½Z
H$U© AB 2AD 3
cot30°=gb½Z
{dê$ÜXAD 3BD
ii) 600 À¶m {ÌH$moU{‘VrMr JwUmoÎmao
sin 60° =AD 3AB 2
cos 60° =BD 1AB 2 tan 60° =
AD 33
BD 1
cosec 60° =AB 2AD 3 sec 60° =
AB 2 2BD 1
cot 60° =BD 1AB 3
iii) 0° Am{U 90° À¶m {ÌH$moU{‘VrMr JwUmoÎmao
g‘Om H$mQ>H$moZ {ÌH$moU ABC, Á¶m ‘ܶo ABC 90 H$ënZm H$am
bKwH$moZ A, Oa eyݶ hmoB©n¶ªV bhmZ Ho$bm Va ˶mÀ¶m {ÌH$moU{‘VrÀ¶m JwUmoÎmamMo
H$m¶ hmoB©b.
{ZarjU H$am, AC Am{U AB À¶m bm§~rMo H$m¶ hmoVo?
Og Ogm, A bhmZ Am{U bhmZ hmoVmo Voìhm BC ~mOyMr bm§~r H$‘r hmoVo. Ogm C q~Xÿ B q~XÿÀ¶m
Odi ¶oVmo. AC hr AB bm V§VmoV§V OwiVo.
• Ooìhm A , 0° À¶m AJXr Odi ¶oVmo Voìhm BC Mr bm§~r eyݶmÀ¶m AJXr Odi ¶oVo.
sin A =BCAC
eyݶmÀ¶m AJXr Odi.
• Ooìhm A , 0° hmoVmo Voìhm AC Mr bm§~r Odi-Odi AB BVH$s hmoVo.
cos A =ABAC
1 ˦m AJXr Odi.
g‘Om Ooìhm A 0 Va sin A Am{U cos A Mm AW© ñnï> H$ê$.
A B
C
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332 UNIT-13
Amåhr Ago ñnï> H$aVmo H$s sin 0° = 0 Am{U cos 0° = 1
AmVm {ÌH$moU{‘VrMr BVa JwUmoÎmao g‘OyZ KoD$.
tan 0° =sin0 0
0cos 0 1
cot 0° =1 1
tan0 0¶m qH$‘VrMr ñnï> ì¶m»¶m Zmhr.
(^mJmH$ma ho eyݶmZo ñnï> H$aVm ¶oV Zmhr)sec 0° =
1 11
cos0 1 cosec 0° =
1 1sin0 0
¶m qH$‘VrMr ñnï> ì¶m»¶m Zmhr.
AmVm H$ënZm H$am H$s A dmT>dyZ Am{U 90° n¶ªV dmT>dyZ {ÌH$moU{‘VrÀ¶m qH$‘VrMo H$m¶ hmoVo?
Og Ogm A ‘moR>m ‘moR>m hmoVmo, C bhmZ Am{U bhmZ hmoVmo Voìhm AB ~mOyMr bm§~r H$‘r hmoVo.
Ogm A q~Xÿ B q~XÿÀ¶m Odi ¶oVmo Am{U eodQ>r Ooìhm A , 90° À¶m AJXr Odi ¶oVmo,
C , 0° À¶m AJXr Odi ¶oVmo Voìhm AC Odi-Odi BC BVH$m hmoVmo.
• Ooìhm A , 90° À¶m AJXr Odi AgVmo Voìhm AC, BC bm V§VmoV§V OwiVo.
sin A =BCAC
1 ˦m AJXr Odi.
• Ooìhm A , 90° À¶m AJXr Odi AgVmo AB Mr bm§~r OdiOdi 0 BVH$s H$‘r hmoVo.
cos A =ABAC
0 ˦m AJXr Odi.
Amåhr Ago ñnï> H$aVmo H$s, sin 90° = 1 Am{U cos 90° = 0
AmVm {ÌH$moU{‘VrMr BVa JwUmoÎmao g‘OyZ KoD$.
tan 90° =sin90 1cos 90 0
¶m qH$‘VrMr ñnï> ì¶m»¶m hmoV Zmhr.
cot 90° =cos 90 0sin90 1
0
sec 90° =1 1
cos 90 0¶m qH$‘VrMr ñnï> ì¶m»¶m hmoV Zmhr.
cosec 90° =1 1 1
sin90 1
AmVm AmnU 0°, 30°, 45°, 60° Am{U 90° À¶m {ÌH$moU{‘VrÀ¶m JwUmoÎmam§Mm Vº$m(H$moï>H$) H$ê$.
¶m H$moï>H$mMm Cn¶moJ CXmhaUo gmoS>{dʶmgmR>r V¶ma g§X^© åhUyZ hmoVmo.
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Trigonometry 333
AmR>dm
¶oWo à‘m{UV H$moZm§gmR>r sin À¶m qH$‘VtMo gmono H$moï>H$ ~Z{dʶmMr H¥$Vr {Xbr Amho.
nm¶ar 1 : 0 Vo 4 n¶ªV g§»¶m {bhm 0 1 2 3 4
nm¶ar 2 : à˶oH$ g§»¶obm 4 Zo ^mJm04
14
24
34
44
nm¶ar 3 : ˶m§Mo dJ©‘yi ¿¶m 014
12
34 1
012
12
32
1
¶m qH$‘Vr sin gmR>r AmhoV 00 300 450 600 900
nm¶ar 4 : qH$‘Vr CbQ> H«$‘mV {bhm 132
12
12 0
¶m qH$‘Vr cos gmR>r AmhoV 00 300 450 600 900
nm¶ar 5 : Amnë¶mbm ‘m{hV Amho tancosSin 0
1
1232
12
12
3212
10
013 1 3 ND
nm¶ar 6 : à‘m{UV H$moZm§gmR>r sin cos Am{U tan ¶m§Mo ì¶ñV ¿¶m. Amåhmbm AZwH«$‘ocosec Sec Am{U cot ¶m§À¶m qH$‘Vr {‘iVmV.
0 30 45 60 90
31 1sin 0 12 223 1 1cos 1 02 22
1tan 0 1 33
2cosec 2 2 13
2sec 1 2 23
1cot 3 1 03
ND
ND
ND
ND
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334 UNIT-13
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1 : Imbrb qH$‘Vr H$mT>m.
(i) tan2 60° + 2 tan2 45°
AmnUmbm ‘m{hV Amho tan 600 = 3 Am{U tan 450 = 1
tan2 60° + 2 tan2 45 = 2 23 2.(1) = 3 + 2 = 5
(ii) Cosec 60° – sec 45° + cot 30°
Amnë¶mH$S>o Amh o cosec 60 ° =23 , sec 45° = 2 Am{U cot 30° = 3
g‘Om cosec 60° – sec 45° + cot 30° =2
2 33 =
2 6 3 5 63 3
(iii) sin2 4 + cos2 4 – tan2 3
1sin sin45
4 2,
1cos cos 45
4 2Am{U tan tan60 3
3
=2 21 1 3
2 2
2
=1 1 32 2 = 1 – 3 = –2
(iv)22
cos0.sin .cos .sec2 6 4tan cot3 3
H$moï>H$mdê$Z cos 0 = 1
sin 2 = sin 90° = 1 sec sec 45 24
tan tan60 33
3cos cos 306 2
1cot cot60
3 3
qH$‘Vr dmnê$Z
2231 1 . 2 31 1 22 4
1 3 133 3
=3 3 3 32 4 8
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Trigonometry 335
CXmhaU 2: Oa 2 cos = 1 Am{U hm bKwH$moZ Amho, Voìhm Mr qH$‘V {H$Vr?
CH$b : 2 cos ho J¥hrV cos12
Amnë¶mbm ‘m{hV Amho cos12 cos cos
CXmhaU 3 : Oa tan Am{U hm bKwH$moZ Agob Va sin 3 Am{U cos2 À¶m qH$‘Vr H$mT>m.
CH$b : tan ho J¥hrV tan 13
Amåhmbm ‘m{hV Amho tan 30 0 = 13tan
2 Am{U 3 Sin 3 Sin 900 = 1
Cos 2 = cos 600 =12
CXmhaU 4 : Oa A = 600, B = 300 Va {gÕ H$am.
cos (A + B) = cosA. cosB - SinA, sinBCH$b : LHS = Cos (A+B) = Cos (600 + 300 = cos 900 = 0 RHS = CosA. CosB- SinA. Sin B = Cos 600 , cos 300 - Sin 600 , Sin 300
=1 3 3 12 2 2 2
=3 34 4
= 0
LHS = RHS
ñdmܶm¶ 13.2
I. Imbrb àým§Mr CÎmao Úm :
(1) 00 nmgyZ 900 n¶ªVÀ¶m H$moU˶m H$moZm§Mr {ÌH$mU{‘VrMr JwUmoÎmao 0 ~amo~a AgVrb?
(2) 00 nmgyZ 900 n¶ªVÀ¶m H$moU˶m H$moZm§Mr {ÌH$moU{‘VrMr JwUmoÎmao 1 ~amo~a AgVrb?
(3) 00 nmgyZ 900 n¶ªVÀ¶m H$moU˶m H$moZm§Mr {ÌH$moU{‘VrMr JwUmoÎmao 12 ~amo~a AgVrb?
(4) 00 nmgyZ 900 n¶ªVÀ¶m H$moU˶m H$moZm§À¶m {ÌH$moU{‘VrÀ¶m JwUmoÎmam§Mr ì¶m»¶m H$aVm ¶oV Zmhr?
(5) 00 nmgyZ 900 n¶ªVÀ¶m H$moU˶m H$moZm§§Mr {ÌH$moU{‘VrMr JwUmoÎmao g‘mZ AgVmV?
II. H$mT>m, Oa 0 900 Am{U
(i) 2 cos (ii) 3 tan = 1 (iii) 2 sin 3
(iv) 5 sin (v) 2 tan
III. Imbrb qH$‘Vr H$mT>m.
(i) Sin 300 cos 600 - tan2 45 0
(ii) Sin 600 cos 300 + cos 600 sin 300
(iii) cos 600 cos 300 - Sin 600 sin 300
(iv) 2 sin2 300 - 3 cos2 300 + tan 600 + 3 sin2 900
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336 UNIT-13
CB
A
(v) 4 sin2 600 + 3 tan2 300 - 8 sin 450 . cos 450
(vi)0
0 0
cos 45Sec 30 + cosec 30
(vii)2 2
2 2
4 Sin 60° - cos 45°tan 30° + sin 0°
(viii) Sin 300 + tan 450 - Cosec 600 (ix) 5 cos2 600 + 4 sec2 300 - tan2 450
Sec 300 +Cos 600 + cot 450 Sin2 300 + cos2 300
(x) 5 Sin2 300 + cos2 450 - 4 tan2 300
2Sin 300 +Cos 300 + tan 450
IV. Imbrb g‘mZVm {gÕ H$am.(i) Sin 300, Cos 600 + cos 300. Sin600 = Sin 900
(ii) 2cos2 300-1 = 1-2 Sin2 300 = cos 600
(iii) Oa Va 4 cos2 - 3 cos 00 = cos 3 ho {gÕ H$am.
(iv) Oa = 1800 Am{U A =6
{gÕ H$am( 1- cosA) (1+ cosA) 1(1-SinA) (1+SinA) 3
(v) Oa B = 150, {gÕ H$am 4 sin 2B, cos4B. Sin6B= 1
(vi) Oa A= 600 Am{U B = 300, Va {gÕ H$am H$s tan (A - B) =tan A - tan B
1 + tan A. tan B{ÌH$moU{‘VtMr g‘mZVm (Trigonometric identities) :
~rOJ{UVm‘ܶo ñ‘aU H$am Vwåhr gyÌo (identities) Aä¶mgbobr AmhoV.
CXmhaUmW©, (a + b)2 = a2 + 2ab + b2 hr EH$ g‘mZVm Amho. a d b ¶m MbnXm§À¶m H$moU˶mhr
qH$‘VrgmR>r ho g‘rH$aU g˶ Amho. ˶mMà‘mUo H$moZmÀ¶m {ÌH$moU{‘VrÀ¶m JwUmoÎmamMm g‘mdoe AgUmao g‘rH$aU
åhUOoM "{ÌH$moU{‘VrMr g‘mZVm", Oa g‘mdoe AgUmè¶m H$moU˶mhr H$moZm§À¶m qH$‘VrgmR>r g˶ Agob Va.
AmVm Amåhr {ÌH$moU{‘VrÀ¶m ˶mM g‘mZVm {‘idy.
g‘Om ABC hm H$mQ>H$moZ {ÌH$moU Amho, Á¶m‘ܶo B 90
nm¶W°JmoagÀ¶m à‘o¶mdê$Z, Amåhmbm {‘iVo AB2 + BC2 = AC2
g‘rH$aUmÀ¶m à˶oH$ nXmg AC2 Zo ^mJyZ Amåhmbm {‘iVo.
2 2
2 2
AB BCAC AC
=2
2
ACAC
2 2AB BCAC AC
=2AC
AC
(cos A)2 + (sin A)2 = 1
sin2 A + cos2 A = 1 ............ (i)
0 A 90 ¶m gma»¶m H$moZ A À¶m gd© qH$‘VrgmR>r ho g‘rH$aU g˶ Amho.
ho g‘rH$aU (1) hr {ÌH$moU{‘VrMr ‘yb yV g‘mZVm Amho.
‘yb yV g‘mZVodê$Z AmVm AmUIr XmoZ {ÌH$moU{‘VtÀ¶m g‘mZVm {‘idy.
sin2 A + cos2 A = 1 ............ (i)
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Trigonometry 337
(i) bm sin2 A Zo ^mJyZ Amåhmbm {‘iVo2 2
2 2 2
sin A cos A 1sin A sin A sin A
2 2sin A cos A 1sin A sin A sinA
1 + (cot A)2 = (cosec A)2
2 21 cot A cosec A ...............(ii)
0° < A 90° ¶m gma»¶m H$moZ A H$moU˶mhr qH$‘VrgmR>r {ÌH$moU{‘VrMr g‘mZVm (ii) hr g˶ AgVo.A 0 gmR>r cot A Am{U cosec A Mr ì¶m»¶m hmoV Zmhr.
(i) bm cos2 A Zo ^mJyZ Amåhmbm {‘iVo.2 2
2 2 2
sin A cos A 1cos A cos A cos A
2 2
2 2 2
sin A cos A 1cos A cos A cos A
(tan A)2 + 1 = (sec A)2
2 2tan A 1 sec A ......(iii)
0 A 90 ¶m gma»¶m H$moZ A À¶m H$moU˶mhr qH$‘VrgmR>r {ÌH$moU{‘VrMr g‘mZVm (iii) hr g˶
AgVo. A 90 gmR>r, tan A Am{U sec A Mr ì¶m»¶m hmoV ZmhrV.
{ÌH$moU{‘VrÀ¶m g‘mZVm (i), (ii) Am{U (iii) ¶mZm ‘yb yV g§~§Y åhUVmV.(1) sin2 A + cos2A = 1(2)tan2 A + 1 = sec2 A(3) 1 + cot2 A = cosec2 A¶m g‘mZVm nwÝhm Imbrbà‘mUo Aemhr {b{hVm ¶oVrb.
sin2 A + cos2A = 1 sin2 A = 1 – cos2 A; qH$dm cos2 A = 1 – sin2A
tan2 A + 1 = sec2 A tan2 A = sec2 A – 1; qH$dm sec2 A – tan2 A = 1
1 + cot2 A = cosec2 A cot2 A = cosec2 A -1; qH$dm cosec2 A – cot2 A = 1
à˶oH$ {ÌH$moU{‘VrMo JwUmoÎma Xþgè¶m {ÌH$moU{‘VrÀ¶m JwUmoÎmamÀ¶m g§X^m©V 춺$ H$aʶmgmR>r ¶m g‘mZVm§MmAmnU Cn¶moJ H$ê$ eH$Vmo. åhUOoM ¶mn¡H$s EImXo JwUmoÎma ‘m{hV Agob Va BVa {ÌH$moU{‘VrÀ¶m JwUmoÎmamMrqH$‘V Amåhr H$mTy> eH$Vmo.
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1: cos . cosec = cot ho {gÕ H$am
CH$b : LHS cos . cosec
= 1cos .sin
1cosecsin
Amnë¶m gmo¶rgmR>r (sin A)2 hosin2A Ago {b{hVmV Am{U gmB©Zñ¹o$Aa A Ago dmMVmV.
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338 UNIT-13
cossin
= cot = RHS
n¶m©¶r nÕV Amåhmbm ‘m{hV Amho H$s COì¶m ~mOy (RHS) ‘ܶo cot =cossin
S>mì¶m ~mOybm Amnë¶mH$S>o cos Amho na§Vw1
cos .sin
Zmhr ˶mEodOr cosec Amho.
åhUyZ1cos .
sin ho cosec Ago {bhrVmV.
cos cosec cos 1cos .
sin= cot
CXmhaU 2 : tan A. sin A + cos A = sec A ho XmIdm.
CH$b : g‘Om LHS = tan A . sin A + cos A
= sin A.sin A cos A
cos Asin A
tanAcos A
)
=2sin A
cos Acos A
=2 2sin A cos A
cos A ( sin2A+cos2 A=1)
= 1cos A
= sec A = RHS
CXmhaU 3 : (sin + cos )2 + (sin – cos )2 Mr qH§$‘V H$mT>m.
CH$b : (sin + cos )2 + (sin - cos )2
=sin2 + cos2 + 2sin cos + sin2 + cos2 – 2sin cos
= 2[sin2 + cos2 ] = 2(1) = 2 sin2 + cos2 ]
CXmhaU 4 : cos2 = 2
11 tan
ho {gÕ H$am.
CH$b : LHS = cos2 = 2 2
1 1sec 1 tan
= RHS
Xþgar nÕV RHS= 22 2
1 1 cos1 tan sec
= LHS
CXmhaU 5 : (1 - sin2A) (1 + tan2A) = 1 ho XmIdm.
CH$b : g‘Om LHS = (1 – sin2A) (1 + tan2 A) = cos2 A . sec2 A [ 1 – sin2 A = cos2 A Am{U 1 + tan2 A=sec2 A
= cos2A . 2
1cos A
= 1 = RHS
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Trigonometry 339
ñdmܶm¶ 13.3
I) Imbrb CXmhaUo {gÕ H$am.
1. (1-sin2 ). sec2 = 1 2. (1+tan2 ). cos2 = 1
3. (1+tan2 )(1-sin (1+sin = 1 4. {gÕ H$am H$s1 cos 2 cosec
1 cosSin
Sin
5. 21 sin(sec tan )
1 sin6. cos sin
1 tan 1 cotA A
A A= sin A + cosA
7.2
22
1 tan 1 2sin1 tan
A AA
8. (sin + cos )2 = 1 + 2 sin .cos
9 . sin A. cos A. tan A + cos A. sin A . cot A = 1
10 {gÜX H$am H$s 2
tan sin sec1 cossin
A A AAA
11. tan2 A - sin2 A = tan2A. sin2 A
12. cos2 A - sin2 A = 2 cos2A - 1
H$moQ>rH$moZm§Mr {ÌH$moU{‘VrMr JwUmoÎmao : (Trigonometric Ratios of Complementary angles)
AmnU H$moQ>rH$moZm§~Ôb ¶mnyduM n[a{MV AmhmoV.
AmR>dU H$am, Oa XmoZ H$moZm§Mr ~oarO 90° Agë¶mg Vo H$moQ>rH$moZ AmhoV Ago åhUVmV.
EH$‘oH$m§Mo H$moQ>rH$mooZ AgUmè¶m XmoZ H$moZm§Mm g‘mdoe Agboë¶m {ÌH$moU{‘VrMr JwUmoÎmao Amåhr H$er 춺$ H$ê$
eH$Vmo?
g‘Om ABC ‘ܶo ABC 90 . ABC ‘Yrb H$moQ>rH$moZm§Mr OmoS>r
AmoiIm. Á¶m AWu B 90 , A C 90
A Am{U C ho H$moQ>rH$moZ AmhoV.
H$moU˶mhr H$mQ>H$moZ {ÌH$moU‘ܶo, H$mQ>H$moZ gmoSy>Z BVa XmoZ bKwH$moZ Zoh‘r H$moQ>rH$moZm§Mr
OmoS>r ~Z{dVmV.
AmVm Aem H$moQ>rH$moZm§gmR>r {ÌH$moU{‘VrÀ¶m JwUmoÎmam§Mr ì¶m»¶m ñnï> H$ê$.
Á¶m AWu A C 90 A 90 C qH$dm C 90 A
[Amnë¶m gmo¶rgmR>r ho H$moQ>rH$moZ (90° – C) qH$dm (90° – A) Ago {b{hVmV.]
A Am{U (90° – A) gmR>rMr {ÌH$moU{‘VrMr JwUmoÎmao Imbrb V³Ë¶m‘ܶo {Xbr AmhoV ˶m§Mo {ZarjU H$am.
CB
A
A
90-A0
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340 UNIT-13
H$moZ A $gmR>r {ÌH$moU{‘VrMr JwUmoÎmao $H$moZ (90° – A) gmR>r {ÌH$moU{‘Vr JwUmoÎmao
sin A =BCAC
sin (90° – A) =ABAC
cos A =ABAC
cos (90° – A) =BCAC
tan A =BCAB
tan (90° – A) =ABBC
cot A =ABBC
cot (90° – A) =BCAB
sec A =ACAB
sec (90° – A) =ACBC
cosec A =ACBC
cosec (90° – A) =ACAB
$H$moZ A Am{U ˶mÀ¶m H$moQ>rH$moZmÀ¶m JwUmoÎmam§Mr VwbZm H$am. Amåhmbm Ago AmT>iVo.
sin (90° – A) = cos A = ABAC
cosec (90° – A) = sec A = ACAB
cos (90° – A) = sin A = BCAC
sec (90° – A) = cosec A = ACBC
tan (90° – A) = cot A = ABBC
cot (90° – A) = tan A = BCAB
Amåhr Agm {ZîH$f© H$mT>Vmo H$s,sin (90° – A) = cos A cosec (90° – A) = sec Acos (90° – A) = sin A sec (90° – A) = cosec Atan (90° – A) = cot A cot (90° – A) = tan A
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1: $qH$‘V H$mT>m0
0
sin65cos 25
CH$b : Amåhmbm ‘m{hV Amho
cos 250 = sin (900-250) = sin 650
0
0
sin65cos 25 =
0
0
cos 25cos 25 =1
$CXmhaU 2: Oa tan 2A = cot (A 180), OoW o 2A hm bKwH$moZ Amho, Va A Mr qH$‘V H$mT>m.
CH$b : Á¶mAWu tan 2 A = cot (900 2A) Amåhmbm {‘iVo cot (900 2A) = cot (A 180)
900 2A = A 180
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Trigonometry 341
3A = 1080 A =0108
3= 360 A = 360
$CXmhaU 3: {gÕ H$am : [cosec (90 – ) – sin (90 – ) [cosec – sin ].[tan + cot ] = 1
CH$b : LHS = [sec – cos ] [cosec – sin ] [tan + cot ]
=1 1 sin coscos sin
cos sin cos sin
=2 21 cos 1 sin 1. .
cos sin cos .sin
=2sin
cos
2cos.
sin1
.cos sin = 1 = RHS
$CXmhaU 4:sin(90 ) cos1 sin 1 cos(90 ) = 2 sec ho {gÕ H$am
CH$b : LHS =sin(90 ) cos1 sin 1 cos(90 )
= cos cos1 sin 1 sin
= 2
cos (1 sin ) cos (1 sin )1 sin
= cos cos sin cos cos sin21 sin
= 2cos 2 2seccos cos
= 2 sec =RHS
ñdmܶm¶ 13.4
1. qH$‘Vr H$mT>m.
(i)0
0
tan65cot 25 (ii)
0
0
sin18cos 72 (iii) cos 480 sin 420
(iv) cosec 310 sec 590 (v) cot 340 tan 560(vi)0 0
0 0
sin36 sin54cos54 cos 36
(vii) sec700 sin200 cos 700 cosec 200 (viii) cos2 130 sin2 770
2. {gÕ H$am
(i) sin 350 sin 550 - cos 350 cos 550 = 0(ii) tan 100 tan 150 tan 750 tan 800 = 1
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342 UNIT-13
(iii) cos 380 cos 520 - sin 380 sin 520 = 03. Oa sin 5 = cos 4 , OoW o 5 Am{U 4 ho bKwH$moZ AmhoV, Va Mr qH$‘V H$mT>m.
4. Oa sec 4A = cosec (A-200), OoWo 4A hm bKwH$moZ Amho Va A Mr qH$‘V H$mT>m.
C§Mr Am{U A§Va (Heights and Distances)
Amåhr ‘moOnÅ>r qH$dm bm§~r ‘moOʶmÀ¶m ’$sVrZo H$m§hr dñVy§Mr C§Mr CXmhaUmW© ‘wbJm, nwVim, PmS>B˶mXr ‘moOʶmg n[a{MV AmhmoV. Aem àH$maÀ¶m ‘moOʶmbm à˶j ‘mnZ åhUVmV.
{Z˶ X¡Z§{XZ OrdZmV Aer H$m§hr {R>H$mUo (n[apñWVr) AgVmV H$s OoWo à˶j ‘mnZ H$ê$Z C§Mr H$mT>Vm¶oV Zmhr. CXmhaUmW© C§M B‘maVrMr C§Mr, ‘Zmoè¶mMr C§Mr, PmS> Xÿa AgUmam nd©V ZXrMr é§Xr B˶mXr.
Aer ‘mnZo Aà˶j ‘mnZ nÕVrZo H$ê$Z ˶m§Mo ‘moO‘mn H$mT>Vm ¶oVo.
bm§~r qH$dm C§MrMo Aà˶j ‘mnZ H$aʶmÀ¶m EH$m CÎm‘ nÕVr‘ܶo JwUmoÎmam§Mm g‘mdoe AgVmo. {Z˶OrdZmVrb KQ>Zoer g§~§{YV g‘ñ¶m gmoS>{dʶmgmR>r {ÌH$moU{‘Vr‘ܶo {dñV¥V Cn¶mo{OVm AmhoV.
C§Mr Am{U A§Va H$mT>Uo hr {ÌH$moU{‘VrMr ‘w»¶ Cn¶mo{OVm Amho. {ÌH$moU{‘VrÀ¶m JwUmoÎmam§Mm Cn¶moJ~m§YH$m‘mMr ¶moOZm, Ajm§e Am{U aoIm§emÀ¶m g§X^m©V ~oQ>mMo ñWmZ {ZpíMV H$aʶmg XoIrb hmoVmo.
AmVm Aem H$m§hr nXm§Mm AW© ñnï> H$ê$ H$s Á¶m§Mm Cn¶moJ C§Mr Am{U A§Va H$mT>ʶmg dma§dma hmoVmo.
Ñï>rMr aofm (Line of Sight)Imbrb AmH¥$˶m§Mo {ZarjU H$am.
¶oWo gm‘mdbobo A§Va IynM ‘moR>o Amho Am{U åhUyZ Ñî¶ åhUOoM dñVydarb EH$m q~XÿMo {ZarjU qH$dmdñVy hmM q~Xÿ Amho Ago JhrV Yamdo.
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Trigonometry 343
{ZarjH$mÀ¶m S>moù¶mnmgyZ dñVydarb q~Xÿn¶ªV H$mT>bobr aofm åhUOoM Ñï>rMr aofm
Ñï>r aofm hr O{‘ZrÀ¶m nmVirbm g‘m§Va AgUmar {j{VO g‘m§Va aofm.
na§Vw Zoh‘rM Ñï>r aofm hr {j{VO g‘m§Va aofm AgVoM Ago Zmhr.
Imbrb AmH¥$˶m‘ܶo {ZarjUmÀ¶m q~XÿMo {Z[ajU H$am.
AmH¥$Vr (i) ‘ܶo EH$ ‘wbJm ‘mZd§XZm XoʶmgmR>r P|S>çmMo {ZarjU H$aVmo. P|S>m {j{VO g‘m§Va nmVirÀ¶m
da Amho Am{U ‘wbmZo dñVy nmhʶmgmR>r S>moHo$ da Ho$bo Amho. ¶m H¥$Vr‘ܶo S>moio, Ñï>raofm Am{U {j{VO g‘m§Va
aofm ¶m‘ܶo V¶ma Pmboë¶m H$moZm‘ܶo hmbVmV. ¶m H$moZmbm Cƒ nmVirVrb H$moZ (angle of elevation)åhUVmV.
AmH¥$Vr (ii) §‘ܶo EH$ ‘wbJm EH$m hmoS>rMo {Z[ajU H$aVmo H$s Or {j[VO g‘m§Va nmVirÀ¶m Imbr Amho.
¶mgmR>r ‘wbJm Amnbo S>moHo$ (S>moio) dñVy nhmʶmg Imbr H$aVmo ¶m H¥$Vr‘ܶo XoIrb S>moio, Ñï>raofm Am{U g‘m§Va
aofm ¶m‘ܶo V¶ma Pmboë¶m H$moZm‘ܶo hmbVmV. ¶m H$moZmbm [Zƒ nmVirVrb H$moZ (angle of depres-sion) åhUVmV.
darb CXmhaUmdê$Z Amåhr Agm {ZîH$f© H$mT>Vmo H$s
q~XÿMo {ZarjU H$aVm ¶oUmam Cƒ nmVirVrb H$moZ hm Ñï>raofoZo {j{VO g‘m§Va aofoÀ¶m da AgUmè¶m q~XÿMo
{ZarjU H$aʶmgmR>r Ho$bobm H$moZ Amho. Cƒ nmVirVrb H$moZ {j{VOmnmgyZ daÀ¶m ~mOyg ‘moOVmV.
q~XÿMo {ZarjU H$aVm ¶oUmam [Zƒ nmVirVrb H$moZ hm Ñï>raofoZo {j{VO g‘m§Va aofoÀ¶m Imbr AgUmè¶m
q~XÿMo {Z[ajU H$aʶmgmR>r Ho$bobm H$moZ Amho. Amnë¶m S>moù¶mdarb H$moZ {j{VOmnmgyZ Imbrb ~mOyg
‘moOVmV.
Q>rn :
* Cƒ nmVirVrb H$moZ Am{U {Zƒ nmVirVrb H$moZ ho Zoh‘r {j{VOmer ‘moObo OmVmV.
* {ZarjH$mZo nm{hbobm dñVyMm Cƒ nmVirVrb H$moZ hm dñVynmgyZ {XgUmè¶m {ZarjH$mÀ¶m Zrƒ nmVirVrb
H$moZm BVH$mM AgVmo.* {ZarjH$mMr C§Mr Oa {Xbr Zgob Va {ZarjH$ hm q~Xÿ åhUyZ KoVbobm AgVmo.
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344 UNIT-13
CB
A
50‘ r300
50‘ r
5 0‘ r
RQ
P
ho ‘m{hV Amho : O{‘ZrMr ‘moOUr H$aUmè¶m bmoH$mZr {ÌH$moU{‘VrMm Cn¶moJ AZoH$eVH$mnmgyZ Ho$bm Amho. EH$mo{Ugmì¶m eVH$m‘Yrb {~«Q>re ^maVr¶m§Mm "J«oQ> {Q>¾m°‘o{Q>H$gìh}' hm EH$ Agm ‘moR>çm ‘moOUrMm àH$ën hmoVm H$s ˶mgmR>r AmS>do d C o H$moZ‘moOʶmgmR>r AmVmn¶ªV gdm©V ‘moR>r Aer XmoZ ‘moOUr ¶§Ìo ~m§YʶmV Ambr hmoVr.1852 ‘Yrb gd}jUmÀ¶m doir OJmVrb gdm©V C§M nd©VmMm emoY bmJbm hmoVm. 1856‘ܶo ¶m {eIambm ga Om°O© EìhaoñQ> Ago Zm§d XoʶmV Ambo H$s Á¶mZo A{V àM§S> Aem‘moOUr ¶§ÌmMm àW‘ Cn¶moJ Ho$bm Am{U gmon{dbobr H$m‘{Jar Ho$br (~mOyÀ¶m AmH¥$Vr ‘ܶo nhm) AmS>do Am{UC o H$moZ ‘moOʶmMo ‘moOUrXmam§Mo ¶§Ì AmVm S>ohamSy>Z ‘Yrb gìh} Am°’$ B§{S>¶m ¶m dñVyg§J«hmb¶m‘ܶo àX{e©VHo$bo Amho.
ho gd}jUmMo Ago CnH$aU Amho H$s Á¶mMm Cn¶moJ {ZarjH$mMm S>moim Am{U dñVy ¶m‘Yrb H$moZmMo ‘mnZH$aʶmg Ho$bm OmVmo. ho {ÌH$moU{‘VrÀ¶m VËdmda Adb§~yZ Amho Am{U H$moZmMo dmMZ Jmob {’$aUmè¶mXþ{~©Urdarb ^mnZ nÅ>rda Ho$bo OmVo.
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1: O{‘Zrda EH$ ‘Zmoam b§~ê$nmV C^m Amho. ‘Zmoè¶mÀ¶m nm¶mnmgyZ 50 ‘r bm§~ Agboë¶m O{‘ZrdarbEH$m q~XÿnmgyZ ‘Zmoè¶mÀ¶m nm¶mnmgyZ AgUmam Cƒ nmVirVrb H$moZ 30° Amho. ‘Zmoè¶mMr C§Mr H$mT>m.
CH$b : {Xboë¶m ‘m{hVrÀ¶m g§X^m©V AmH¥$Vr H$mT>m. g‘Om AB hr ‘Zmoè¶mMr C§Mr (h)Am{U BC ho ‘Zmoam Am{U {ZarjH$mMm q~Xÿ ¶m‘Yrb A§Va Amho.
ABC ‘ܶo, ACB = 300
tan 30° = ABBC = h
501 h
503= h =
503 ‘r.
CXmhaU 2: ‘Zmoè¶mda 50 ‘r C§Mrda EH$ dñVy AgyZ {ZarjH$ Am{U ‘Zmoè¶mMm nm¶m¶m‘Yrb A§Va 50 ‘r Agë¶mg Cƒ nmVirVrb H$moZ H$mT>m.
CH$b : g‘Om PQ hr dñVyMr C§Mr = 50 ‘r.
QR ho {ZarjH$ Am{U ‘Zmoè¶mÀ¶m nm¶m‘Yrb A§Va = 50 ‘r. PQR ‘ܶo PQR = 900
tan =PQ 50
1QR 50
tan = 1 = tan 450 ( tan 45° = 1)‘r.tan = tan 450 = 45°
Cƒ nmVirVrb H$moZ 45° Amho.
CXmhaU 3: 50 3 ‘r. C§M Agboë¶m B‘maVrÀ¶m ‘m϶mnmgyZ O{‘Zrdarb H$maMm ZrÀM nmVirVrb H$moZ 60°Agë¶mMo {XgyZ ¶oVo. H$maMo B‘maVrnmgyZ AgUmao A§Va H$mT>m.
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Trigonometry 345
CH$b: g‘Om B‘maVrMr C§Mr PQ Zo Xe©{dbr OmVo, PQ = 50 3 ‘r. QR ho B‘maV Am{U H$ma ¶m‘YrbA§Va Amho.
ZrÀMnmVirVrb H$moZ 600 Amho.
Á¶m AWu, PM || QR, åhUyZ MPR PRQ ( ì¶wËH«$‘ H$moZ)
MPR 60 PRQ 60
PQR ‘ܶo, PQR 90 , PRQ 60
tan 60° =PQ 50 3QR QR
3 =50 3QR QR =
50 3
3 = 50
H$ma hr B‘maVrnmgyZ 50 ‘r A§Vamda Amho.
CXmhaU 4 : EH$m eoVO{‘ZrÀ¶m à˶oH$ ~mOyg EH$ Aem 50 ‘r. Am{U 40 ‘r. C§MrÀ¶m XmoZ ndZ M³³¶m
AmhoV. EH$ 춺$s ‘Zmoè¶m‘Yrb EH$m q~XÿnmgyZ ndZ M¸$sÀ¶m ‘m϶m§Mo {ZarjU H$aVoo. XmoÝhr KQ>Zm‘ܶo Cƒ
nmVirVrb H$moZ 450 Agë¶mMo {XgyZ ¶oVo. ndZM¸$s‘ܶo AgUmao A§Va H$mT>m.
CH$b : CXmhaU ì¶d{ñWV dmMyZ ‘m{hVrMo ê$nm§Va AW©nyU© AmH¥$VrV H$am.
A
B
C
DP
g‘Om ‘Zmoè¶mMr C§Mr AB = 50 ‘r. Amho.
CD hr Xþgè¶m ‘Zmoè¶mMr C§Mr = 40 ‘r.
{ZarjU 'P' ¶oWo Amho Am{U Cƒ nmVirVrb H$moZ APB CPP 45
BD = BP + PD ho BD ‘Yrb A§Va Amho.
ABP ‘ܶo, tan =ABBP
tan 45° =50BP
P
Q R
M = 60°
60°?
50 3
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346 UNIT-13
1 =50BP ( tan 45° = 1)
BP = 50 m
CPD ‘ܶo, tan =CDPD
tan 45° =40PD ( tan 45° = 1)
1 =40PD PD = 40 ‘r.
BD = BP + PD = 50 + 40 = 90 ‘r.
eoVmÀ¶m XmoÝhr ~mOyg AgUmè¶m ndZM¸$s‘Yrb A§Va 90 ‘r. Amho.
ñdmܶm¶ 13.5
I. Imbrb CXmhaUmVrb 'x' Mr qH$‘V H$mT>m :
(i)x
60 ‘t45°
(ii)
x
90
60°
R
P Q
(iii)x
30°100
K
ML
(iv)
x
100
45°
X
Y Z
(v)75
75
D
F Ex
II. 1. gy¶m©Mr g‘wÐgnmQ>rnmgyZ C§Mr ({j{VOmer Agbobm H$moZ) 300 AgVmZm EH$m C§M ‘Zmoè¶mMr
gmdbr 300 ‘r bm§~ nS>Vo. Va ‘Zmoè¶mMr C§Mr H$mT>m.
2. 50 3 ‘rQ>a C§MrÀ¶m B‘maVrÀ¶m ‘m϶mdê$Z O{‘Zrdarb dñVyÀ¶m {Zƒ nmVirVrb H$moZmMo ‘mn
45° Agë¶mMo AmT>iVo. Va dñVyMo B‘maVrnmgyZMo A§Va H$mT>m.
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Trigonometry 347
3. EH$ PmS> dmè¶mZo VwQ>Vo Am{U O{‘Zrbm H$mQ>H$moZ {ÌH$moU H$aVo Oa ‘moS>bobm ^mJ O{‘Zrer 60°
H$moZ H$aVmo Am{U PmS>mMm ‘mWm AmVm ˶mÀ¶m nm¶mnmgyZ 20 ‘r. da Amho. Va PmS> {H$Vr C§MrMo
hmoVo?
4. {j{VOm darb O{‘ZrÀ¶m EH$m q~XÿnmgyZ ÜdOñV§ mÀ¶m (flagpost) ‘m϶mdarb Cƒ nmVirVrb
H$moZ 30° Agë¶mMo {XgyZ ¶oVo. ñV§ mÀ¶m {XeoZo 6 ‘r. MmbV Joë¶mda nmVirVrb H$moZ 15° Zo
dmT>Vmo Va ÜdOñV§ mMr C§Mr H$mT>m.
5.EH$m B‘maVrÀ¶m ‘mWm Am{U Vi ¶mnmgyZ EH$m C§M H$S>çmMo Cƒ nmVirVrb H$moZ AZwH«$‘o 45° Am{U
60° AmhoV. Oa B‘maVrMr C§Mr 24 ‘rQ>a Agob Va H$S>çmMr C§Mr H$mT>m.
6.16 ‘rQ>a C§M B‘maVrÀ¶m ‘m϶mdê$Z EH$m Q>oH$S>rÀ¶m ‘m϶mdarb Cƒ nmVirVrb H$moZ 60° Am{U
Q>oH$S>rÀ¶m nm¶mer AgUmam {ZÀM nmVirVrb H$moZ hm 30° Amho. Va Q>oH$S>rMr C§Mr H$mT>m.
7.Oa 150 g|.‘r C§MrMm {ZarjH$ gmdbrÀ¶m Q>moH$mH$S>o nmhVmo Omo nm¶mnmgyZ 150 3 go.‘r. Amho. Va
{Zƒ nmVirVrb H$moZ H$mT>m.
8.O{‘ZrnmgyZ 50 ‘rQ>a da AgUmè¶m q~XÿnmgyZ T>JmMm Cƒ nmVirVrb H$moZ 30° Am{U ˶mÀ¶m
à{Vq~~mMm Zrƒ nmVirVrb H$moZ 60° Amho. O{‘ZrnmgyZ da AgUmè¶m T>JmMr C§Mr H$mT>m.
D
{ÌH$moU{‘Vr
{ÌH$moU{‘VrMr JwUmoÎmao {ÌH$moU{‘VrMr gyÌo C§Mr Am{U A§Va H$mT>Uo
sin cos tan sec cosec cot sin2A+cos2A=1 Cƒ nmVirVrb H$moZ
{ÌH$moU{‘VrÀ¶m JwUmoÎmamMm ì¶ñV 1+ co+2A=cosec2A
{ÌH$moU{‘VrÀ¶m JwUmoÎmamVrb g§~§Y tan2A+ 1= sec2A {Zƒ nmVirVrb H$moZ
{ÌH$moU{‘VrÀ¶m JwUmoÎmamMoà‘m{UV H$moZ 00, 300, 450, 600, 900 H$moQ>r H$moZm§À¶m {ÌH$moU{‘VrMo JwUmoÎma
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348 UNIT-13
CÎmao
ñdmܶm¶ 13.1
I. (i)2425
,725
(ii)35
,45
(iii)5
13,
1213
II. (i)53 (ii)
2524 (iii)
247 (iv) (v)
34 (vi)
817
III. (1)3 4,5 5
(2)20 29,29 21
(3)7 24 7, ,25 25 24
,257
,2524
,247
(4)12 , 3 , 3
(5)1 3
,10 10 , 3 (6) 3 ,
231
,13 , 3 (7)
3 4 5 5, , ,5 5 4 3
(8)1265
(9) (10)177
ñdmܶm¶ 13.2
II. (i) 45° (ii) 30° (iii) 60° (iv) 0º (v) 30°
III.(i)34
(ii) 1 (iii) 0 (iv)5 34
(v) 0 (vi)3
2 2 1 3
(vii)152 (viii)
33
33
44
(ix)6712 (x)
56 4 3
ñdmܶm¶ 13.4
1. (i) 1 (ii) 1 (iii) 0 (iv) 0 (v) 0 (vi) 0 (vii) 0 (viii) 0
3. = 10° 4. A = 22°
ñdmܶm¶ 13.5
I (i) 60 ‘r (ii) 30 3 EH$Ho$ (iii)100
3 EH$Ho$ (iv)100
2 EH$Ho$ (v)4
EH$Ho$
II (1) 100 3 ‘r (2) x = 50 3 ‘r (3) 20 3 2 ‘r (4)6
3 1 ‘r
(5)24243 1+( ) ‘t (6) 64 ‘r (7) 30º (8) 100 ‘r
*****
177
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¶m KQ>H$m‘wio Vwåhmbm ¶m§Mo gwb^rH$aU hmoVo.
* gh{ZX}eH$ Ajm§À¶m AWm©Mo ñnï>rH$aU.
* gh{ZX}eH$ Aj H$mT>Uo.
* gh{ZX}eH$ nmVir‘ܶo {Xboë¶m q~Xÿ§Mo ñWmZ {ZpíMVH$aUo.
* ax + by = c g‘rH$aUmMm AmboI gaiaofoZo Xe©{dbmOmVmo ho AmoiIUo.
* gaiaofoMm MT> ¶mMm AW© ñnï> H$aUo.
* {Xboë¶m aofoÀ¶m MT>mMm {heo~ H$aUo.
* aofoÀ¶m x- Am§VaN>oX Am{U y - Am§VaN>oX ¶m§À¶m AWm©Moñnï>rH$aU.
* gai aofoÀ¶m g‘rH$aUmMo MT> Am§VaN>oX ñdê$n {‘i{dUo.
* nmVirVrb XmoZ q~Xÿ‘Yrb A§VamMm {heo~ H$aUo.
* aofobm {Xboë¶m JwUmoÎmamV {d^mJUmè¶m gh{ZX}eH$ q~Xÿ§Mm{heo~ H$aUo.
* ‘yb^yV H$ënZm - gh{ZX}eH$ Aj,Ama§ q~Xÿ.
* q~XÿMo gh{ZX}eH$ {b{hUo.
* ax + by = c Mm AmboI(aofr¶ AmboI)
* gai aofoMm MT>.
* MT>-Am§VaN>oX ñdê$nmVrb gaiaofoMrg‘rH$aUo.
* nmVirVrb XmoZ q~Xÿ‘Yrb A§Va.
* nmVirVrb q~XÿMo CJ‘mnmgyZMo A§Va.
* I§S> gyÌ.
14
aoZ. {S>ñH$mQ>©g²[1596 - 1650]
hm ’«|$M V§ËdkmZr, J{UVVk Á¶mÀ¶m
'La geometrie' ¶m H$m‘mMm g‘mdoe
y{‘VrMm ~rOJ{UVm‘ܶo Agm dmna
Á¶m‘wio Ambm Amnë¶mH$S>o
"H$mQ>}{g¶Z' y{‘Vr Amho.
Mathematics is the only place where truth andbeauty mean the samething.
- Danica Mckellar
gh{ZX}eH$ ^y{‘VrCo-ordinate Geometry
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350 UNIT-14
Amåhr ghOnUo {ZarjU H$aVmo H$s Q>oH$S>rÀ¶m ‘m϶mn¶ªV nmohmoMUmaoañVo Zoh‘r diUmdiUmMo AgVmV. Q>oH$S>rÀ¶m ‘m϶mn¶ªV gai OmUmao añVoZgVmV. H$m?
darb àýmMo CÎma XoʶmgmR>r Amåhr Aä¶mgboë¶m Cn¶wº$ Am¶VmH¥$Vrgh{ZX}eH$ nÕVrÀ¶m H$ënZoMm {dMma H$ê$.
’«|$M VËdkmZr Am{U J{UVVk (aoZ S>oñH$mQ>©g²) (1546-1950) ¶mZo‘w»¶Ëd J{UVmMr emIm {dH$grV Ho$br åhUyZ Am¶VmH¥$Vr gh{ZX}eH$ nÕVrbm˶mMmdê$Z ""H$mV}{g¶Z nÕV'' Ago Zm§d nS>bo.
ho J{UVmÀ¶m Aem emIoH$S>o KoD$Z OmVo H$s Á¶mbm ""gh{ZX}eH$ y{‘Vr qH$dm n¥W…H$aUmË‘H$ ^y{‘VråhUVmV.
hr J{UVrMr Aer emIm Amho H$s Or y{‘Vrbm ~rOJ{UVmà‘mUodmJ{dVo.
AmVm g‘Om H$mV}{e¶Z nÕVrÀ¶m g§~§YmV AgUmao eãX AmR>dy.
* XmoZ b§~ aofmZm gh{ZX}eH$ Aj åhUVmV.
* {j{VO g‘m§Va (AmS>dr) aofm X'OX bm x- Aj åhUVmV.
* C^r aofm YOY' bm y- Aj åhUVmV.
* XmoÝhr Ajm§À¶m N>oXZq~Xÿbm Ama§ q~Xÿ 'O' åhUVmV.
gh{ZX}eH$ AjmZo nmVir Mma ^mJm‘ܶo {d^mJbr OmVo.
H$mV}{g¶Z (Cartesian) nmVirVrb q~Xÿ {df¶r.
i) ˶mÀ¶m y- AjmnmgyZÀ¶m b§~ A§Vambm q~XÿMo x- gh{ZX}eH$(ABSCISSA) åhUVmV.
ii) ˶mÀ¶m x- AjmnmgyZÀ¶m b§~ A§Vambm q~XÿMo y- gh{ZX}eH$(ORDINATE) åhUVmV.
i) 'p' q~XÿMo gh{ZX}eH$ p(x, y) Zo Xe©{dVmV.
ii) Ama§ q~XÿMo gh{ZX}eH$ (0, 0)ho AmhoV.
iii) x- Ajmdarb H$moU˶mhr q~XÿMo gh{ZX}eH$ (x, 0) ¶mñdê$nmV AgVmV.
iv) y- Ajmdarb H$moU˶mhr q~XÿMo gh{ZX}eH$ (0, y)
ñdê$nmV AgVmV.
‘m{hVr H$ê$Z ¿¶m.ABSCISSA d ORDINATEho b°Q>rZ eãX AmhoV.ABSCISSA åhUOo VwH$S>o Ho$bobo.ORDINATE åhUOo Vo H«$‘mV R>odUo.
OXI X
Y
YI
II-x, + y( )
III
-x, - y( )
MaUMaU
MaU MaU
I+x, + y( )
IV+x, - y( )
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Coordinate Geometry 351
ax + by = c ¶m ñdê$nmMr g‘rH$aUo AmboImZo Xe©{dUo.
aofr¶ g‘rH$aUm§À¶m AmboIm{df¶r Vwåhr n[a{MV AmhmV. Imbrb g‘rH$aUm§À¶m AmboIm§Mo {Z[ajUH$am.
(1)2x + y = 7
y = mx + c À¶m ñdê$nmV ê$nm§Va Ho$ë¶mg Amåhmbm
{‘iVo, y = 7 – 2x
0 1 2 37 5 3 1
xy
(2)3x + 2y = 5
ho g‘rH$aU y =5 3
2- x
Ago nwÝhm {bhm.
0 1 1 32.5 1 4 2
--
xy
darb CXmhaUmdê$Z Ago ñnï> hmoVo H$s ax + by = cñdê$nmVrb AmboI Zoh‘r gai aofm AgVo.
Q>rn … aofm AmboI aMʶmgmR>r XmoZ q~Xþ nwaogo AmhoV. AmUIr EH$ qH$dm XmoZ q~Xÿ VnmgʶmgmR>r qH$dm{ZpíMVrgmR>r KoVbo.
O
87654321
–1–2–3–4–5–6
1 2 3 4 5–1–2–3–4–5
(0, 7)
(1, 5)
(2, 3)
(3, 1)XI X
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–1–2–3
1 2 3–1–2–3
(3, –2)
(–1, 4)(0, 2.5)
(1, 1)XI X
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352 UNIT-14
gaiaofoMm CVma (Inclination of straight line)
2x + y = 7 Am{U 3x + 2y = 5 ¶m g‘rH$aUm§gmR>r {‘iUmè¶m AmboIm§Mo {ZarjU H$am.
AB Am{U CD ¶m gaiaofm x- Ajmer H$moZ V¶ma H$aVmV. hm H$moZ KS>çmimÀ¶m {XeoZo Am{U KS>çmimÀ¶m{déÕ {XeoZo Aem XmoÝhr {XemZr ‘moOVm ¶oVmo.
x- AjmÀ¶m YZ {Xeoer aofr¶ AmboImZo V¶ma Ho$boë¶m H$moZmbm ˶m aofoMr CVaU åhUVmV.hm H$moZ gm‘mݶnUo ‘ ’ Zo Xe©{dbm OmVmo.
gai aofoMr CVaU (inclination) hm Agm H$moZ, H$s Omo x- AjmÀ¶m N>oXZq~Xÿer V¶ma hmoVmo Am{U OmoYZ {XeoZo AgVmo. hm H$moZ x- AjmÀ¶m KS>çmimÀ¶m {déÕ {XeoZo aofoer ‘moObm OmVmo.
Q>rn … Ooìhm AjmnmgyZ aofoer KS>çmimÀ¶m {déÕ {XeoZo H$moZ ‘moObm OmVmo Voìhm aofoMr CVaU hr eyݶmnojm‘moR>r AgVo Aer na§nam Amho.
aofoMm MT> (Slope of a line)
Imbrb CXmhaUm§Mo {ZarjU H$am.
{eS>r q^Vrbm Aer bmdyZ R>odbr Amho H$s {VMm ‘mWm(darb Q>moH$) O{‘ZrnmgyZ EH$m {d{eï> C§Mrda q^Vrbm ñne©H$aVmo.
Q´>H$‘ܶo AmoPo ^aVmZm H$m‘Jma bmH$S>r ’$irMm Cn¶moJH$aVmV Vmo CVa˶m pñWVr‘ܶo Agë¶mZo Q>H$‘ܶo AmoPo^aUo ˶mZm gmono OmVo.
B‘maVrMm {OZm {d{eï> pñWVr‘ܶo ~m§Ybobm AgVmo H$sÁ¶m‘wio {OZm MT>ʶmMm VmU H$‘r hmoVmo.
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Coordinate Geometry 353
darb à˶oH$ CXmhaUm‘ܶo {eS>r/bmH$S>r ’$ir/{OZm Aem pñWVr‘ܶo AgVmo H$s MT>ʶmMm VmU H$‘rhmoVmo.
q^VrnmgyZ {H$Vr A§Vamda {eS>r R>odmdr H$s ˶m‘wio VmU H$‘rV H$‘r hmoB©b?
Imbrb VrZ AmH¥$˶m§Mm Aä¶mg H$am. JQ>m‘ܶo MMm© H$am Am{U CH$b J{UVr nÕVrZo H$mT>ʶmMm à¶ËZH$am.
(1) (2) (3)C B
AA
BC BC
A
XmoZ bm§~tMo JwUmoÎma KoD$Z ho H$aVm ¶oVo. åhUOo b§~ C§Mr Am{U AmS>do A§Va bjmV R>odm H$s à˶oH$KQ>Zo‘ܶo {eS>rMr bm§~r gmaIrM AgVo.
darb AmH¥$˶m‘ܶo, {Z[ajU H$am H$s AB BC Am{U ABC H$mQ>H$moZ {ÌH$moU Amho.
¶oWo, AB bm b§~ A§Va (C§Mr) Am{U CB bm {jVrO (AmS>do) A§Va åhUVmV.
A
BC 4.7 cm
1.6 cm
A
BC 3.5 cm
3.5
cm
A
BC 2.6 cm4.
3cm
AmS>do A§VaC~o A§Va
AmS>do A§VaC~o A§Va
AmS>do A§VaC~o A§Va
AB 1.6cm 0.34BC 4.7 cm
AB 3.5cm 1BC 3.5 cm
AB 4.3cm1.65
BC 2.6 cm
à˶oH$ CXmhaUm‘ܶo, {‘iUmè¶m JwUmoÎmambm AC aofoMm MT> åhUVmV.
b§~ A§VamMo {jVrO A§Vamer AgUmè¶m JwUmoÎmambm MT> åhUVmV.
AmS>do A§VaC~o A§Va
darb CXmhaUm‘ܶo,
KQ>Zm (1), AB < BC KQ>Zm (2), AB = BC KQ>Zm (3), AB > BC.
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354 UNIT-14
Amåhr {ZarjU H$aVmo H$s,
* Ooìhm b§~ A§Va ho {jVrO A§Vamnojm H$‘r AgVo Voìhm MT> 1 nojm H$‘r AgVmo.
* Ooìhm b§~ A§Va ho {jVrO A§VamBVHo$ AgVo Voìhm MT> 1 AgVmo.
* Ooìhm b§~ A§Va ho {jVrO A§Vamnojm OmñV AgVo Voìhm MT> 1 nojm A{YH$ AgVmo.
Ooìhm MT> 1 nojm H$‘r AgVmo Voìhm MT>ʶmMm VmU H$‘rV H$‘r AgVmo.
aofoMm MT> {ÌH$moU{‘Vr JwUmoÎmamV gwÕm 춺$ Ho$bm OmD$ eH$Vmo. Imbrb CXmhaU Aä¶mgm.
aofoMm MT> hm ˶mÀ¶m CVaUrÀ¶m H$moZmÀ¶m ñn{e©Ho$ BVa AgVmo. hm gm‘mݶnUo 'm' Zo Xe©{dbm OmVmo.m = tan
gaiaofoÀ¶m MT>mdmMo ‘mZ (Gradient of a straight line)
gaiaofoÀ¶m MT>mdmÀ¶m ‘mZmMr ì¶m»¶m
y ‘Yrb dmT>
x ‘Yrb dmT>aofodarb EH$m q~XÿnmgyZ Xþgè¶m q~XÿH$S>o hmoUmar
hmbMmb Aer H$aVm ¶oVo.
MT>mdmMo ‘mZ (Gradinet) =BCAC
yx
åhUyZ, MT>mdmMo ‘mZ =b§~ C§Mr
AmS>do A§VagaiaofoÀ¶ MT>mdmMo ‘mZ hm Ho$di aofoMm MT> Amho.
Q>rn …
1. x- Aj ñdV…er 0° H$moZ A§mV[aV H$aVmo.åhUyZ x- AjmMm MT> hm m = tan = 0 [ = 0°]
2. y-Aj, x Ajmer 90° Mm H$moZ A§V[aV H$aVmo.åhUyZ, y- AjmMm MT> hm m = tan 90° = 춺$ H$aVm ¶oV Zmhr. [ = 90°]
ABC ˦m ~m~VrV
AC Mm MT> =ABBC
BC ~mOyer AC H$moZ ~Z{dVo.
H$moZm˦m ~m~VrV,
AB hr {déÕ ~mOy Am{U BC hr gb¾ ~mOy
MT> ={déÕ ~mOy
gb¾ ~mOy
MT> = tan
C
A
B
AmS>do A§Va
C~oA
§Va
A
BC
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Coordinate Geometry 355
3. H$moZmÀ¶m CVaUrMr qH$‘V MT>mMr qH$‘VValue of slope
= 0° 0
0° < < 90° YZ g§»¶m = 90° 춺$ H$aVm ¶oV Zmhr
90° < < 180° F$U g§»¶m
AmVm Vwåhr g‘Oy eH$mb H$s nd©Vmda KoD$Z OmUmao añVo ‘m϶mn¶ªV gai H$m ZgVmV.
Vw‘Mo {‘Ì Am{U {ejH$m§~amo~a MMm© H$am.
{Xboë¶m XmoZ q~XÿVyZ OmUmam gai aofoMm MT>
g‘Om H$mV}{g¶Z àVbmda A(xI, yI) Am{U B(x2, y2)
ho H$moUVohr XmoZ {ZpíMV q~Xÿ AmhoV.
AL x-Aj, BM x-Aj, AN BM H$mT>m.
AmH¥$Vrdê$Z, OL= x1, OM = x2
LM= x2 – x1 = AN
AL= y1 = NM, BM = y2
BN= y2 – y1
ABN ‘ܶo, BAN =
˦m ~m~VrV, tan =BNAN
MT> = tan =2 1
2 1
y yx x
m = 2 1
2 1
y - yx - x
{Xboë¶m XmoZ {ZpíMV q~Xÿ‘YyZ OmUmam gai aofoMm MT>
={Xboë¶m q~Xÿ§Mm y- gh{ZX}eH$m§Mm ’$aH$
˶m§À¶m x- gh{ZX}eH$m§Mm ’$aH$
Vwåhr gaiaofoMm MT> H$mT>ʶmMo {eH$bm AmhmV gma»¶mM H$mV}{g¶Z nmVirVrb XmoZ aofm§Mo MT>H$mT>md¶mMo AmhoV, Ago g‘Om.
o
y
( ,,y)x 22
A(,
)x
y 1
1
( – )x2 x1
x2
Lx1 MXI X
Y
YI
y1
(–
)y
y2
1
y 2
B
N ( – )x2 x1
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356 UNIT-14
g‘m§Va aofm (Parallel lines)XmoZ g‘m§Va aofm x-Ajmer gmaImM CVma H$aVmV. åhUyZ
˶mZm gmaImM MT> AgVmo.= [ g§JV H$moZ]
tan = tan
= MT> AB = Mm MT> CD.
g‘m§Va aofmZm g‘mZ MT> AgVmV.CbQ> AWu, Oa XmoZ aofm§Mo MT> g‘mZ AgVrb Va ˶m aofm
EH$‘oH$m§Zm g‘m§Va AgVmV.
Q>rn :
* x - Ajmbm MT> 0 Amho. x - Ajmbm g‘m§Va AgUmè¶m H$moU˶mhr aofoMm MT> XoIrb 0 Amho.
* y- Ajmbm MT> 춺$ H$aVm ¶oV Zmhr. y- Ajmbm g‘m§Va AgUmè¶m H$moU˶mhr aofoMm MT> XoIrb 춺$ H$aVm ¶oV Zmhr.
b§~ aofm (Perpendicular lines)Oa AB hr CD bm b§~ Agob Va ˶m§Mo CVma AZwH«$‘o Am{U AgVmV.
= 90 + [ ~møH$moZ = Am§Va{déÕ H$moZm§Mr ~oarO]tan = tan (90 + )
tan = – cot [ tan (90 + ) = – cot ]
tan =1
tan tan . tan = – 1
m1 : m2 = –1OoWo m1 AB Mm MT>
m2 CD Mm MT>
m1 =2
1m qH$dm m2 =
1
1m
Oa XmoZ aofm EH$‘oH$m§Zm b§~ AgVrb Va, ˶m§À¶m MT>m§MmJwUmH$ma -1 AgVmo.
CbQ> AWu, Oa XmoZ aofm§À¶m MT>m§Mm JwUmH$ma -1 Agob Va ˶maofm EH$‘oH$m§Zm b§~ AgVmV.
ñnï>rH$aUmË‘H$ CXmhaUo
1. Á¶m aofoMm CVma 60° Amho Va aofoMm MT> H$mT>m.CH$b … = 60°
MT> = m = tanm = tan 60°
m = 3
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Coordinate Geometry 357
2. Á¶m aofoMm MT> 0 Amho ˶m aofoÀ¶m CVmamMm H$moZ H$mT>m.CH$b … MT> = tan
0 = tan
Amåhmbm ‘m{hV Amho, tan 0 = 0
= 0°
3. (3, –2) Am{U (4, 5) q~Xÿ OmoS>Umè¶m aofoMm MT> {ZpíMV H$am.CH$b … (x1, y1) = (3, –2) (x2, y2) = (4, 5)
MT> =2 2
2 1
y yx x =
5 ( 2)4 3 = 5 2
1MT> = 7
4. {gÕ H$am H$s (4, 5) Am{U (0, –2) q~Xÿ OmoS>Umar aofm hr (2, –3) Am{U (–5, 1) q~XÿVyZ OmUmè¶m aofobmb§~ AgVo.
CH$b … aofm 1 gmR>r : (x1, y1) = (4, 5), (x2, y2) = (0, – 2)
MT> =2 1
2 1
y yx x =
2 50 4
MT> =74
= m1
Xþgè¶m aofogmR>r … (x1, y1) = (2, –3), (x2, y2) = (–5, 1)
MT> =2 1
2 1
y yx x =
1 ( 3)5 2
=1 3
7
MT> =47
= m2
m1 × m2=7 44 7
= –1
˶m§À¶m MT>m§Mm JwUmH$ma -1 Amho.
XmoÝhr aofm b§~ AmhoV.
5. P(7, 3) Am{U Q(0, –4) ¶m q~XÿVyZ OmUmam aofoMm MT> H$mT>m. VgoM (i) PQ bm g‘m§Va(ii) PQ bm b§~ AgUmè¶m aofoMm MT> H$mT>m.
CH$b (x1, y1) = (7, 3) (x2, y2) = (0, –4)
MT> =2 1
2 1
y yx x =
4 30 7
=77
MT> = 1
PQ Mm MT> = 1
(i) PQ bm g‘m§Va AgUmè¶m aofoMm MT> = 1 [ g‘m§Va aofm§gmR>r, m1 = m2](ii) PQ bm b§~ AgUmè¶m aofoMm MT> = – 1 [ b§~ aofm§gmR>r, m1 × m2 = –1]
1
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358 UNIT-14
ñdmܶm¶ 14.1
1. aofm§Mm MT> H$mT>m Oa ˶m§Mm CVma(i) 90° (ii) 45° (iii) 30° (iv) 0°
2. gai aofm§À¶m CVmamMo H$moZ H$mT>m Á¶m§Mo MT>
(i) 3 (ii) 1 (iii) 13
3. q~Xÿ OmoS>Umè¶m aofm§Mo MT> H$mT>m.(i) (–4, 1) Am{U (–5, 2) (ii) (4, –8) Am{U (5, –2)
(iii) (0, 0) Am{U 3,3 (iv) (–5, 0) Am{U (0, – 7) (v) (2a, 3b)Am{U (a, –b)
4. q~XÿÀ¶m XmoZ OmoS>çm‘YyZ OmUmè¶m aofm H$mT>ë¶mg ˶m g‘m§Va AgVmV qH$dm b§~ AgVmV ho H$mT>m.(i) (5, 2), (0, 5) Am{U (0, 0), (–5, 3) (ii) (3, 3), (4, 6) Am{U (4, 1), (6, 7)
(iii) (4, 7), ( 3, 5) Am{U (–1, 7), (1, 6) (iv) (–1, –2), (1, 6) Am{U (–1, 1), (–2, –3)
5. q~Xÿ OmoS>Umè¶m aofmZm b§~ AgUmè¶m aofoMm MT> H$mT>m.(i) (1, 7) Am{U (–4, 3) (ii) (2, –3) Am{U(1, 4)
6. q~Xÿ OmoS>Umè¶m aofm§Zm g‘m§Va AgUmè¶m aofoMm MT> H$mT>m.(i) (–4, 3) Am{U (2, 5) (ii) (1, –5) Am{U (7, 1)
7. (2, 7) Am{U (3, 6) q~XÿVyZ OmUmar aofm (9, a) Am{U (11, 3) ¶m q~XÿZm OmoS>Umè¶m aofobm g‘m§VaAgob Va a H$mT>m.
8. (1, 0) Am{U (4, 3) q~XÿVyZ OmUmar aofm (–2, –1) Am{U (m, 0) ¶m q~XÿZm OmoS>Umè¶m aofobm b§~Agob Va m Mr qH$‘V H$mT>m.
MT> Am§VaN>oX ñdê$nmVrb aofoMo g‘rH$aU (Equation of a line in slope intercept form)
aofr¶ AmboImMo {ZarjU H$am. PQ gaiaofm hr x- Ajmbm P Am{U yAjmbm Q ‘ܶo N>oXVo.
OP A§Va åhUOoM, Ama§ q~XÿnmgyZ x- Ajmdarb N>oXZq~Xÿn¶ªV A§Va¶mbm aofoMm x- Am§VaN>oX åhUVmV.
OQ A§Va åhUOoM, Ama§ q~XÿnmgyZ y-Ajmdarb N>oXZ q~Xÿn¶ªVMo A§Va¶mbm aofoMm y -Am§VaN>oX åhUVmV.
darb CXmhaUm‘ܶo x-Am§VaN>oX 3 AgyZ y-Am§VaN>oX 4 Amho.Imbrb KQ>Zm‘ܶo x Am{U y Am§VaN>oX AmoiIm.
O
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1 2 3–1–2–3P
Q
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Coordinate Geometry 359
O
4321
–1–2–3–4
1 2–1–2XI X
Y
YI
O
54321
–1–2–3
1 2 3–1–2–3XI X
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YI
AmVm Imbrb AmboImMm Aä¶mg H$am.g‘Om aofm 'l ' y-Ajmbm A(0,c) ‘ܶo {‘iVo.OA hm l aofoMm y-Am§VaN>oX Amho.g‘Om P hm l aofodarb H$moUVmhr q~Xÿ Amho.PQ OX Am{U AB PQ H$mT>m.
g‘Om H$s 'l ' hm x-Ajmer Q H$moZ H$aVmo.PAB = (g§JV H$moZ)MT> = m = tan
m ={déÕ ~mOyg§b¾ ~mOy
PAB ‘ܶo, g§b¾À¶m ~m~VrV
m =PBAB
[PB = PQ – BQ, AB = OQ]
m =cy
xmx = y – c
y = mx + c
'm' MT> Agbobo Am{U Á¶mMm y-Am§VaN>oX hm 'c' Agbobo g‘rH$aU y = mx + c Ago {Xbo Amho.
ñnï>rH$aUmË‘H$ CXmhaUo
1. MT> ½ Am{U y-Am§VaN>oX 3 Agbobo aofoMo g‘rH$aU H$mT>m.
CH$b … m= ½, y Am§VaN>oX = c = – 3g‘rH$aU : y = mx + c
y = ½x + (–3) = ½x – 3
y =6
2x
2y = x – 6
qH$dm x – 2y – 6 = 0
O
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Q xc
x
( –
)y
c
P(, )
xy
(0, c)
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360 UNIT-14
2. CVaUrMm H$moZ 45° Am{U y-Am§VaN>oX 2 Agbobo aofoMo g‘rH$aU H$mT>m.
CH$b … = 45°, y-Am§VaN>oX = C = 2
MT> = m = tan m = tan 45°
m = 1
g‘rH$aU : y = mx + cy = 1(x) + 2 = x + 2
qH$dm x – y + 2 = 0
3. 3x + 2y + 1 = 0 ho aofoMo g‘rH$aU Amho. ˶mMm MT> Am{Uy-Am§VaN>oX H$mT>m.CH$b … g‘rH$aU : 3x + 2y + 1 = 0
y = mx + c ¶m à‘m{UV Z‘wݶmV nwÝhm {bhm.2y = –3x – 1
2 Zo ^mJyZ, Amåhmbm {‘iVo
y =3 12 2
x
y = mx + c er VwbZm H$am
m =32 , c =
12
MT> =32
y Am§VaN>oX =12
ñdmܶm¶ 14.2
1. aofoMo g‘rH$aU H$mT>m, Á¶mMo CVaU H$moZ Am{U y-Am§VaN>oX {Xbo AmhoV.(i) = 60°, y-Am§VaN>oX – 2 Amho. (ii) = 45°, y-Am§VaN>oX 3 Amho.
2. aofoMo g‘rH$aU H$mT>m Á¶mMm MT> Am{U y-Am§VaN>oX {Xbm Amho.(i) MT> = 2, y- Am§VaN>oX = – 4
(ii) MT = 23 , y-Am§VaN>oX = 1
2
(iii) MT = –2, y-Am§VaN>oX = 3
3. aofm§Mo MT> Am{U y-Am§VaN>oX H$mT>m.(i) 2x + 3y = 4 (ii) 3x = y
(iii) x – y + 5 = 0 (iv) 3x – 4y = 5
4. x = 2y hr aofm 2x – 4y + 7 = 0 bm g‘m§Va Amho H$m? (gyMZm … g‘m§Va aofmbm g‘mZ MT> AgVmV.)
5. Ago XmIdm H$s, aofm 3x + 4y + 7 = 0 Am{U 28x – 21y + 50 = 0 EH$‘oH$m§Zm b§~ AmhoV.(gyMZm … b§~ aofm§gmR>r, m1m2 = –1]
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Coordinate Geometry 361
XmoZ q~Xÿ‘Yrb A§Va (Distance between two points)
A Am{U B q~Xÿ§Mo {Z[ajU H$am. ˶m‘Yrb A§Va ho, Vo OmoS>Umè¶m aofmI§S>mMr bm§~r.
A BA BAmåhr aofmI§S>mMr bm§~r qH$dm XmoZ q~Xÿ‘Yrb A§Va ‘moOʶmgmR>r ’y$Q>nÅ>r dmnaVmo.
à˶j Z ‘moOVm XmoZ q~Xÿ‘Yrb A§Va H$mT>Uo e³¶ Amho H$m?
¶mMm Aä¶mg H$aUo ‘Zmoa§OH$ Amho H$s Amåhr ˶m‘Yrb A§VaH$mTy> eH$Vmo, Oa Vo H$mV}{g¶Z àVbmda ñWmnZ Ho$bo AgVrb Va.
Oa A Am{U B q~Xÿ X- Ajmda AgVrb, Va Amåhr A Am{U B‘Yrb EH$H$ aofmI§S>m§Mr g§»¶m ‘moOy eH$Vmo.
AB= 4 cm qH$dm
A Mm gh{ZX}eH$ (1, 0) Am{U B Mm (5, 0)
AB= x2 – x1 = 5 – 1
AB = 4 g|.‘r.
gm‘mݶnUo, Oa A Am{U B Mo gh{ZX}eH$ AZwH«$‘o (x1, 0)Am{U(x2, 0) AgVrb Va AB = x2 – x1.
Oa P Am{U Q ho XmoZ q~Xÿ y-Ajmda AgVrb Va Amåhr P Am{UQ ‘Yrb EH$H$ aofmI§S>m§Mr g§»¶m ‘moOy eH$Vmo.
PQ= 6 g|.‘r. qH$dm
P Mm gh{ZX}eH$ (0, 4) Am{U Q Mm (0, –2)
PQ= y2 – y1 qH$dm PQ = y1–y2
= –2 – 4 = –6 = 4 – (–2) = 6PQ = 6 cm = 6
gm‘mݶnUo, Oa P Am{U Q Mo gh{ZX}eH$ AZwH«$‘o (0, y1) Am{U (0,y2) AgVrb Va PQ = y2 – y1
X- Ajmbm g‘m§Va AgUmè¶m aofoMr bm§~rOa AB X- Ajmbm g‘m§Va AgobAA' X- Aj,BB' x - Aj H$mT>m.AA'B'B Zo V¶ma hmoUmar AmH¥$Vr Am¶V Amho.
AB = A'B'A'B' = x2 – x1 = 6 – 1A'B' = 5 AB = 5 g|.‘r.
Q>rn … X- Ajmbm g‘m§Va AgUmè¶m aofodarb gd© q~XÿZm gmaImMy-gh{ZX}eH$ AgVmo.
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1 2 3 4 5–1–2XI X
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54321
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1 2 3–1–2
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–3
Y
O 1 2 3 4 5 6–1–2–1
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2
AI BI
bjmV R>odm … A§Va ho Zoh‘r YZg§»¶m AgVo.
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362 UNIT-14
y- Ajmbm g‘m§Va AgUmè¶m aofoMr bm§~r
Oa AB, y- Ajmbm g‘m§Va Agob
AA' y-Aj
BB' y-Aj H$mT>m.
AA'B'B Zo V¶ma hmoUmar AmmH¥$Vr Am¶V Amho.AB = A'B'
A'B' = y2 – y1
= –3 – 4 = – 7A'B' = 7 cmAB = 7 cm
Q>rn … y-Ajmbm g‘m§Va AgUmè¶m aofodarb gd© q~XÿZm gmaImMm x-gh{ZX}eH$ AgVmo.
darb gd© CXmhaUm‘ܶo, OoWo Amåhmbm XmoZ q~Xÿ‘Yrb A§Va H$mT>VmZm, XmoZ AQ>r bjmV Amë¶m,* q~Xÿ EH$ Va x-Ajmda AgVmV.
* q~Xÿ Aer aofm ~Z{dVmV H$s Or x-Ajmbm qH$dm y-Ajmbm g‘m§Va AgVo.AmVm H$mV}{g¶Z àVbmdarb P Am{U Q q~XÿMo {ZarjU H$am. P Am{U
Q q~Xÿ x-Aj qH$dm y-Ajmda ZgVmV.g‘Om Vo OmoSy>. aofmI§S> PQ hm aofmI§S> x-Ajmbm qH$dm y-Ajmda
g‘m§Va ZgVmV.AmVm, x qH$dm y Ajmda ZgUmè¶m qH$dm ˶mZm g‘m§Va ZgUmè¶m XmoZ
q~Xÿ‘Yrb A§Va H$go H$mT>Vm ¶oVo Vo Aä¶mgy.
A§VamMo gyÌ (Distance formula)
Oa A(x1, y1) Am{U B(x2, y2) ho {Xbobo XmoZ q~Xÿ AmhoV, BC || yAj Am{U AC || x-Aj H$mT>m. C Mo gh{ZX}eH$ (x2, y1)
AC= x2 – x1 Am{U BC = y2 – y1
ABC H$mQ>H$moZ {ÌH$moU Amho, nm¶W°JmoagÀ¶m à‘o¶mdê$Z,AB2 = AC2 + BC2
AB2 = (x2 – x1)2 + (y2 – y1)
2
AB = 2 22 1 2 1x x y y
(x1, y1) Am{U (x2, y2) ¶m XmoZ q~Xÿ‘Yrb A§Va
d = 2 22 1 2 1x - x + y - y
d = 2 2difference of absscissa difference of ordinates
Q>rn … gmo¶rgmR>r, n{hë¶m MaUm‘ܶo ¶oUmao q~Xÿ gyÌ {‘i{dʶmgmR>r Amåhr KoVbo. na§Vw, H$moU˶mhrMaUm‘ܶo ¶oUmè¶m q~Xÿ§gmR>r gd© gyÌ g˶ AgVmV.
O
54321
–1–2–3
1 2 3 4–1–2
AI
BI
A(2, 4)
B(2, –3)
–3–4XI X
Y
YI
P
Q
OXI X
Y
YI
OXI X
Y
YI
(x- gh{ZX}eH$mVrb ’$aH$)2 (y- gh{ZX}eH$mVrb ’$aH$)2
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Coordinate Geometry 363
àVbmVrb q~XÿMo Ama§^q~XÿnmgyZ AgUmao A§Va.
A(x, y) Am{U O(0, 0) ho XmoZ q~Xÿ {Xbo AmhoV.
A§VamÀ¶m gyÌmdê$Z,
d = 2 22 1 2 1x x y y
d = 2 20 0x y = 2 2x y
ñnï>rH$aUmË‘H$ CXmhaUo
1. (2, 3) Am{U (6, 6) q~Xÿ‘Yrb A§Va H$mT>m.
CH$b … (x1, y1) = (2, 3) Am{U (x2, y2) = (6, 6)
d = 2 22 1 2 1x x y y = 2 26 2 6 3
d = 2 24 3 = 16 9 = 25
d = 5 EH$Ho$
2. Ama§^q~Xÿ Am{U q~Xÿ (12, –5) ¶m‘Yrb A§Va H$mT>m.
CH$b … Ama§^q~Xÿ Am{U (x, y) ‘Yrb A§Va = 2 2x y
¶oW (x, y) = (12, –5)
d = 2 212 ( 5) 144 25 169
d = 13 EH$H$
3. x-Ajmdarb q~Xÿ§Mo gh{ZX}eH$ H$mT>m Oo (6, –3) ¶m q~XÿnmgyZ 5 EH$H$ Xÿa AmhoV.
CH$b … x-Ajmdarb H$moU˶mhr q~XÿMo gh{ZX}eH$ (x, 0) ñdê$nmV AgVmV.
(x1, y1) = (x, 0) Am{U (x2, y2) = (6, –3) Am{U d = 5
d = 2 22 1 2 1x x y y
5 = 22( 6) 0 ( 3)x = 2 2( 6) 3x
XmoÝhr ~mOy§Mm dJ© H$ê$Z, 52 =2
26 9x
25 = x2 – 12x + 36 + 9
x2 – 12x + 45 – 25 = 0 x2 – 12x + 20 = 0 (x – 10)(x – 2) = 0 x – 10 = 0 or x – 2 = 0 x = 10 or x= 2
x - Ajmdarb Amdí¶H$ q~Xÿ (10, 0) Am{U (2, 0)
O(0, 0)
A( , )x y
XI X
Y
YI
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364 UNIT-14
4. x Mr Aer qH$‘V H$mT>m H$s q~Xy (2, 5) Am{U (x, –7) ¶m‘Yrb A§Va 13 Agob.
CH$b … d= 13, (x1, y1) = (2, 5) Am{U (x2, x2) = (x, –7)
d = 2 22 1 2 1x x y y
13 = 2 22 ( 7 5)x = 2( 2) 144x
XmoÝhr ~mOy§Mo dJ© H$ê$Z, 132= x2 – 4x + 4 + 144169 = x2 – 4x +148
x2 – 4x + 148 – 169 = 0x2 – 4x – 21 = 0
(x – 7) (x + 3) = 0 x = 7 qH$dm x = – 3
5. (8, -4), (9, 5) Am{U (0, 4) {eamoq~Xÿ AgUmam {ÌH$moU hm g‘{Û^wO {ÌH$moU Amho Ago XmIdm.
CH$b … {ÌH$moU hm g‘{Û wO Amho ho XmI{dʶmgmR>r Amnë¶mbm {ÌH$moUmÀ¶m 2 ~mOy§Mr bm§~r g‘mZ AgVo hoXmIdmdoM bmJob.g‘Om A(8, –4), B(9, 5), C(0, 4)
d = 2 22 1 2 1x x y y
AB = 2 29 8 5 ( 4) = 2 21 9 1 81 82
BC = 2 2 2 2(9 0) (4 5) 9 ( 1) 81 1 82
CA = 22 2 2(0 8) 4 ( 4) 8 8 64 64 128
Á¶mAWu AB = BC, {ÌH$moU hm g‘{Û wO Amho.
6. {gÕ H$am H$s q~Xÿ A(–3, –2), B(5, –2), C(9, 3) Am{U D(1, 3) ho g‘m§Va^wO Mm¡H$moZmMo{eam oq~Xÿ Amh oV.
CH$b … Mm¡H$moZmÀ¶m g§‘wI ~mOw g‘mZ AgVrb Va Vmo Mm¡H$moZ g‘m§Va^wO AgVmo.
d = 2 22 1 2 1x x y y
AB = 2 25 ( 3) 2 ( 2) = 2 28 0 64 8
CD = 2 2(9 1) (3 3) = 2 28 0 64 8
BC = 2 2 2 2(5 9) ( 2 3) 4 5 16 25 41(
DA = 2 2 2 21 ( 3) 3 ( 2) 4 5 16 25 41
AB= CD Am{U BC = DA
ABCD hm g‘m§Va wOMm¡H$moZ Amho.
B(9, 5)
C(0, 4) A(8, –4)
A(–3, –2) B(5, –2)
C(9, 3)
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Coordinate Geometry 365
ñdmܶm¶ 14.3
1. Imbrb q~Xÿ§À¶m OmoS>çm‘Yrb A§Va H$mT>m(i) (8, 3) Am{U (8, –7) (ii) (1, –3) Am{U (–4, 7) (iii) (–4, 5) Am{U (–12, 3)
(iv) (6, 5) Am{U (4, 4) (v) (2, 0) Am{U (0, 3) (vi) (2, 8) Am{U (6, 8)(vii) (a, b) Am{U (c, b) (viii) (cos – sin ) Am{U (sin – cos )
2. Ama§ q~Xÿ Am{U q~Xÿ ¶m‘Yrb A§Va H$mT>m.(i) (–6, 8) (ii) (5, 12) (iii) (–8, 15)
3. (i) (3, 1) Am{U (0, x) ¶m q~Xÿ‘Yrb A§Va 5 Amho Va x H$mT>m.
(ii) q~Xÿ P(2, –1) hm (a, 7) Am{U (–3, a) ¶m q~XÿnmgyZ g‘mZ A§Vamda Amho Va 'a' H$mT>m.
(iii) y-Ajmdarb q~Xÿ H$mT>m, Omo (5, 2) Am{U (–4, 3) ¶m q~XÿnmgyZ g‘mZ A§Vamda Amho.
4. {ÌH$moUm§Mr n[a{‘Vr H$mT>m Á¶m§À¶m {eamoq~XÿZm Imbrb gh{ZX}eH$ AmhoV.(i) (–2, 1), (4, 6), (6, –3) (ii) (3, 10), (5, 2), (14, 12)
5. {gÕ H$am H$s q~Xÿ A(1, –3), B(–3, 0) Am{U C(4, 1) ho g‘{Û^wO H$mQ>H$moZ {ÌH$moUmMo {eamoq~Xÿ AmhoV.
6. (-5, 4) dVw©i‘ܶ AgUmar Am{U Vr (-7, 1) q~XÿVyZ OmVo Aer dVw©imMr {ÌÁ¶m H$mT>m.
7. {gÕ H$am H$s à˶oH$ gh{ZX}eH$mMo gQ> ho g‘m§Va wO Mm¡H$moZmMo {eamoq~Xÿ AmhoV.(i) (–5, –3), (1, –11), (7. –6), (1, 2) (ii) (4, 0), (–2, –3), (3, 2), (–3, –7)
8. {ÌH$moUmÀ¶m {eamoq~Xÿ§Mo gh{ZX}eH$ {Xbo AmhoV. {ÌH$moUm§Mo àH$ma AmoiIm.(i) (2, 1) (10, 1) (6, 9)(ii) (1, 6) (3, 2) (10, 8)
(iii) (3, 5) (–1, 1) (6, 2) (iv) (3, –3) (3, 5) (11, –3)
I§S> gyÌ (Section Formula)
g‘Om AB aofm, q~Xÿ A(x1, y1) Am{U B(x2, y2) ¶mZm OmoS>VoAm{U P q~Xÿ AB aofmI§S>mbm m : n JwUmoÎmamV {d^mJVo.
APPB =
mn
AmVm, P q~XÿMo gh{ZX}eH$ {‘i{dʶmMm à¶ËZ H$ê$.g‘Om P Mo gh{ZX}eH$ (x, y) AmhoV.x-Ajmda AL, PM Am{U BN ho b§~ H$mT>m.AR PM Am{U PQ BN
AmH¥$Vrdê$Z, AR= LM = OM – OL = x – x1
PR = PM – RM = PM – AL = y – y1
PQ = MN = ON – OM = x2 – xBQ = BN – QN = BN – PM = y2 – y
{ZarjU H$am.
L M NO
–x x2
–x x1
–y y1
R
PA
( , )b x y2 2
( , )x y ( , )x y1 1
–y
y2
Q
XI XYI
Y
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366 UNIT-14
APR~ PBQ
AR PR AP= =PQ BQ PB [ g‘ê$n {ÌH$moUmÀ¶m g§JV ~mOy à‘mUmV AgVmV.]
g‘OmARPQ
= APPB
KoD$.
1
2
x xx x =
mn
nx + mx = mx2 + nx1
x (m + n) = mx2 + nx1
x(m + n) = mx2 + nx1
x = 2 1mx nxm n
PRBQ
=APPB {dMmamV ¿¶m.
1
2
y yy y =
mn
ny – ny1 = my2 – my
ny + my = my2 + ny1
y(m + n) = my2 + ny1
y = 2 1my nym n )
P Mo gh{ZX}eH$ = (x, y)
P Mo gh{ZX}eH$ = 2 1 2 1mx + nx my + ny,m + n m + n
Oa P hm AB Mm ‘ܶq~Xÿ m : n =1:1 Voìhm P Mo gh{ZX}eH$ = 2 1 2 1x + x y + y,2 2
¶mbm ‘ܶ q~Xÿ gyÌ (mid point fomula) Agohr åhUVmV.
ñnï>rH$aUmË‘H$ CXmhaUo
1. P [~§XÿMo gh{ZX}eH$ H$mT>m, Omo A(4, –5) Am{U B(6, 3) bm 2 : 5 ¶m JwUmoÎmamV OmoSy>Z aofobm Xþ^mJVmo.
CH$b …g‘Om P Mo gh{ZX}eH$$ (x, y) J¥hrV … m : n = 2 : 5
(x1, y1) = (4, –5) Am{U (x2, y2) = (6, 3)
I§S> gyÌmdê$Z.
x = 2 1 2(6) 5(4) 12 20 322 5 7 7
mx nxm n
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Coordinate Geometry 367
y = 2 1 2(3) 5( 5) 6 25 192 (.5) 7 7
my nym n P Mo gh{ZX}eH$ =
32 19,7 7
2. q~Xÿ (5, 4), q~Xÿ (2, 1) Am{U (7, 6) aofm§Zm OmoSy>Z {d^mJV Agob Va ˶mMo JwUmoÎma H$mT>m.
CH$b … g‘Om nm{hOo Agbobo JwUmoÎma m : n Amho.
J¥hrV … (x1, y1)= (2, 1) Am{U (x2, y2) = (7, 6), (x, y) = (5, 4)
I§S> gyÌmdê$Z
x = 2 1mx nxm n
qH$dm y = 2 1my nym n
5 =(7) (2)m nm n
4 =(6) (1)m nm n
5 =7 2m nm n
4 =6m nm n
5m + 5n = 7m + 2n 4m + 4n = 6m + n5m – 7m + 5n – 2n = 0 4m – 6m + 4n – n = 0
–2m + 3n = 0 –2m + 3n = 0–2m = –3n –2m = –3mn
mn
=32
mn
=32
m : n = 3 : 2 m : n = 3 : 2
3. q~Xÿ (2, 3) Am{U (4, 7) OmoS>Umè¶m aofmI§S>mÀ¶m ‘ܶq~XÿMo gh{ZX}eH$ H$mT>m.
CH$b …(x1, y1) = (2, 3) Am{U (x2, y2) = (4, 7)
‘ܶq~Xÿ gyÌmdê$Z, ‘ܶq~XÿMo gh{ZX}eH$ = 1 2 1 2,2 2
x x y y
=2 4 3 7,
2 2 =6 10,2 2 = (3, 5)
ñdmܶm¶ 14.4
1) H$moU˶m JwUmoÎmam‘ܶo (-2, 3) q~Xÿ hm (-3, 4) Am{U (4, 9) q~Xÿ OmoS>Umè¶m aofmI§S>mZm {d^mJVmo?2) C(1,1) q~XÿV, A(-2,7) Am{U B OmoS>Umam aofmI§S> 3:2 JwUmoÎmamV {d^mJVmo. Va B Mo gh{ZX}eH$
H$mT>m.3) q~Xÿ (-1, k) hm (-3, 10) Am{U (6, -8) q~XÿZo OmoS>Umè¶m aofmI§S>mbm Xþ mJVmo, Va JwUmoÎma H$mT>m.4) (-3, 10) Am{U (6, -8) q~Xÿ OmoS>Umè¶m aofmI§S>mÀ¶m ‘ܶq~XÿMo gh{ZX}eH$ H$mT>m.5) g‘m§Va wO Mm¡H$moZmMo VrZ H«$‘dma {eamoq~Xÿ A(1,2), B(2,3) Am{U C(8,5) AmhoV. Mm¡Wm {eamoq~Xÿ
H$mT>m. (gyMZm … g‘m§Va wO Mm¡H$moZmMo H$U© EH$‘oH$mZm Xþ mJVmV).
* * *
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368 UNIT-14
CÎmao
ñdmܶm¶ 14.1
1. (i) ND (ii) 1 (iii)13 (iv) 0 2. (i) 60º (ii) 45º (iii) 30º
3. (i) –1 (ii) 6 (iii) 3 (iv) 57- (v) 4b
a 4. (i) g‘m§Va (ii) g‘m§Va (iii) b§~ (iv) g‘m§Va
5. (i)54
(ii)17
6. (i)13
(ii) 1 7) 5
8. –3
ñdmܶm¶ 14.2
1. (i)y = 3 x – 2 (ii) y = x + 3 2. (i) y = 2x – 4 (ii) 6y = –4x + 3 (iii) y =- 2x + 3
3. (i) m = 32- , c = 3
4 (ii) m = 3, c = 0 (iii) m = 1, c = 5 (iv) 3 54 4m = ,c = -
ñdmܶm¶ 14.3 1. (i) 10 EH$Ho$ (ii) 55 EH$Ho$ (iii) 172 EH$Ho$ (vi) 5 EH$Ho$ (v) 13 EH$Ho$ (vi) 4 EH$Ho$
(vii) (c–a) EH$Ho$ (viii) 22 (sin cos )EH$Ho$
2. (i) 10 EH$Ho$ (ii) 13 EH$Ho$ (iii) 17 EH$Ho$ 3. (i) 5 qH$dm –3 (ii) 7 (iii) (0, –2)
4. (i)( )8580 +61 + EH$Ho$ (ii) ( )181125 +68 + EH$Ho$ 6) 13 EH$Ho$
ñdmܶm¶ 14.4
1. 1:6 2. (3, –3) 3. 2:7,k = 6 4. 32 1, 5. (7, 4)
*****
Drawing graph ofequation ax+by=c
Coordinate Geometry
Distance betweentwo points
Inclination of astraight line lying on
axisx-lying on
axisy-Length of line
parallel toaxisx-
Length of lineparallel to
axisy-
2 1
2 1
y ym =x x
Distance Formula2 2
2 1 2 1d ( ) ( y )x x y
Section Formula
p ,2 1 2 1mx +nx my +nym+n m+n
Section Formula
p ,2 1 2 1
2 2x + x y + y
Slope of a straightline, m = tan
gh{ZX}eH$ ^y{‘Vr
XmoZ q~XÿVrb A§Vaax+by=c ¶m g‘rH$aUmMmAmboI H$mT>Uo
gai aofoMm CVma y=Ajmdarb
x=Ajmdarb
x=Ajmbm g‘m§VaaofoMr bm§~r
A§VamMo gyÌ
gai aofoMm MTm=tan I§S>mMo gyÌ (‘ܶ q~Xþ)
I§S>mMo gyÌ
Am§VaN>oX MT>mÀ¶m aofoÀ¶mg‘rH$aUmMo ñdê$n
y = mx+c
b§~ aofm§MmMT>mMm JwUmH$ma -
1 AgVmo
g‘m§Va aofoMmMT> g‘mZAgVmo
y=Ajmbm g‘m§VaaofoMr bm§~r
XmoZ q~XÿVyZ OmUmè¶mgai aofoMm MT>
2 1 2 1x x y y
2 22 1 2 1x x y ym=
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¶m KQ>H$m‘wio Vwåhmbm ¶m§Mo gwb^rH$aU hmoVo,
* d¥Îm{MÎmr, e§Hy$ Am{U JmobmMr ì¶m»¶m H$aUo.* d¥Îm{MÎmr, e§Hy$ Am{U Jmobm§À¶m JwUY‘m©Mo ñnï>rH$aU
H$aUo.* d¥Îm{MÎmr, e§Hy$ Am{U Jmob ¶m§Mo joÌ’$i Am{U KZ’$i
¶m§Mo gyÌ aMUo.* d¥Îm{MÎmr, e§Hy$ Am{U Jmob ¶m§Mo dH«$n¥ð>’$i Am{U
g§nyU© n¥ð>’$i H$mT>Uo.* d¥Îm{MÎmr, e§Hy$ Am{U Jmob ¶m§Mo KZ’$i H$mT>Uo.* d¥Îm{MÎmr, e§Hy$ Am{U Jmob ¶m§Mo joÌ’$i Am{U KZ’$i
¶mda AmYmarV CXmhaU gmoS>{dUo.* e§Hy$À¶m ’«$ñQ>‘À¶m AWm©Mo ñnï>rH$aU H$aUo.* ’«$ñQ>‘ e§Hy$Mo joÌ’$i Am{U KZ’$i H$mT>Uo.* XmoZ qH$dm Am{YH$ KZnXmWm©nmgyZ ~Zboë¶m dñVy§Zm
AmoiIUo.* EH${ÌV KZ nXmWmªMo joÌ’$i Am{U KZ’$i emoYUo.* A{Z¶{‘V AmH$mamÀ¶m AmH¥$˶m§Mm à‘m{UV AmamIS>m
aMUo.* A{Z¶{‘V AmH$mamÀ¶m AmH¥$˶m§Mo joÌ’$i H$mT>Uo.
‘mnZo (Mensuration)15
Give me a place to stand,and I will move the earth.
- Archimedes of Syracuse
* d¥Îm{MVr, e§Hy$, e§Hy$Mm ’«$ñQ>‘,Jmob Am{U AY©JmobmMm AW©.
* d¥Îm{MVr, e§Hy$, e§Hy$Mm ’«$ñQ>‘,Jm ob Am{U AY©JmobmMo dH «$n¥ð>’$i Am{U KZ’$i.
* EH${ÌV AmH¥$˶m, ˶m§Mo joÌ’$iAm{U KZ’$i.
* à‘m{UV AmamIS>m H$mT>Uo.
Am{H©$‘oS>rg Archimedes(287BC-212BC)
gm¶amHw$g Mo Am{H©$‘oS>rg, {ggrbr
ho nwamVZ H$mimVrb EH$ à{gÕ J{UVVk
åhUyZ AmoiIbo OmVmV. ^y{‘Vr‘Yrb
gnmQ > AmH ¥ $˶m §M o j oÌ’ $i Am{U
KZnXmWmªMo joÌ’$i Am{U KZ’$im{df¶r
A˶§V ‘hËdnyU© ¶moJXmZ {Xbo Amho.
˶m §Zr Jm obmM o KZ’$i h o
AY©JmobmÀ¶m KZ’$imÀ¶m XmoZ V¥VrAm§e
AgVo ho {gÕ Ho$bo Amho.
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370 UNIT-15
nXmWmªÀ¶m ‘mnm§Mm Aä¶mg H$aUo A˶§V Amdí¶H$ Amho H$maU {Z˶ OrdZmVrb H$maImZo Am{UA{^¶m§{ÌH$s‘Yrb ˶mÀ¶m Cn¶moJm‘wio KZ KZm¶V$, bmobH$ Am{U {MÎmr ¶m§Mo KZnXmWmªÀ¶m n¥ð>^mJmMo joÌ’$iAm{U KZ’$i H$mT>ʶmMm Aä¶mg Vwåhr nydu Ho$bobm Amho.
‘mnm§er g§~§{YV Agboë¶m AmUIr H$mhr KZ nXmWmªÀ¶m CXmhaUm§Mm {dMma H$é.
• J«m‘ n§Mm¶VrZo d¥Îm{MÎmrÀ¶m AmH$mamMr C§M nmʶmMr Q>mH$s V¶ma Ho$br Amho. Q>mH$sMmAmH$ma H$gm emoYmb? ˶m Q>mH$sbm a§J bmdʶmgmR>r ¶oUmam IM© {H$Vr?
• Q´>H$À¶m d¥Îm{MÎmr AmH$mamÀ¶m B§YZ Q>mH$s‘ܶo gmR>{dbobo {S>PobMo à‘mU Vwåhr H$go H$mT>mb?• dmT>{XdgmMr Q>monr ~Z{dʶmgmR>r bmJUmè¶m a§JrV H$mJXmMo à‘mU {H$Vr?• {Xboë¶m ~ogZ bmSy>À¶m dOZmÀ¶m {‘lUmnmgyZ {H$Vr ~ogZ bmSy> V¶ma Ho$bo OmVmV?
darb Z‘yX Ho$boë¶m gd© CXmhaUmMo CH$b ho KZnXmW© Ogo H$s d¥Îm{MÎmr e§Hy$ Am{U Jmob ¶m§À¶m n¥f^mJmMojoÌ’$i Am{U KZ’$i ¶mda Adb§~yZ Amho.
¶m nXmWmªÀ¶m n¥ð>^mJmMo joÌ’$i Am{U KZ’$i H$go H$mT>bo OmVo? ¶mgmR>rH$moUVr gyÌo dmnabr OmVmV?
¶m KQ>H$m‘ܶo AmnU d¥Îm{MÎmr e§Hy$ Am{U Jmob ¶m§À¶m n¥ð>^mJmMo joÌ’$i Am{U KZ’$i
¶m§Mm Aä¶mg H$aUma AmhmoV.
d¥Îm{MÎmr (Cylinder)
Vwåhr Aä¶mgbobo Amho H$s, Ooìhm AZoH$ Am¶VmH¥$VrH$mJXmMr n¥ð>o EH$‘oH$mda R>odbr Va Amåhmbm KZm¶V qH$dm Am¶VmH¥$VrVimMm bmobH$ {‘iVmo.
Ooìhm EH$ê$n dVw©imda H$mJXmMr n¥ð>o EH$‘oH$mda R>odbr VaAmnë¶mbm H$m¶ {‘iVo? Imbr {Xboë¶m AmH¥$˶m§Mo {ZarjU H$am.
{‘imboë¶m (V¶ma Pmboë¶m) KZnXmWm©bm d¥Îm{MÎmr Ago åhUVmV.d¥Îm{MÎmr ¶m dVw©imH$ma Vi Agboobo bmobH$ AmhoV.
H¥$Vr … EH$ OmS> H$mJX ¿¶m Am{U ABCD ¶m Am¶Vm‘ܶo H$mnm. EH$m ~mOybm EH$ bm§~ H$mR>r {MH$Q>dm. Vmo ABåhUy. Vr Vw‘À¶m XmoÝhm Viì¶mda Yam Am{U OmoamV {’$adm. (Vwåhr EH$ bm§~ Xmoam {MH$Q>dm Am{U Xmoam hmVmVYê$Z XmoÝhr ~mOybm OmoamV {’$adm) hr H¥$Vr JQ>m‘ܶo H$am. MMm© H$am Am{U ¶m ¶w³Ë¶m EH$‘oH$mer {d^mJm.
Vwåhr H$moUVo AmH$ma AmoiIy eH$mb?
darb H¥$Vrdê$Z AmnU Agm {ZîH$f© H$mTy> eH$VmoH$s,
Oa Am¶VmMr EH$ ~mOy pñWa R>odyZ ˶m ^mdVr{’$a{dë¶mZo V¶ma hmoUmè¶m KZnXmWm©bm b§~dVw©imH$ma d¥Îm{MÎmr Ago åhUVmV.
A
BC
D
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Mensuration 371
V w‘À¶m X ¡Z § {XZ OrdZ m‘ܶ o V wåhrd¥Îm{MÎmrÀ¶m AmH$mamÀ¶m AZoH$ dñVy nm{hë¶mAmhoV. ˶mn¡H$s H$m§hr Imbrbà‘mUo {Xbobo AmhoV.
d¥Îm{MÎmr ¶m ^ard qH$dm nmoH$i Agy eH$VmV.{ZarjU H$am H$s d¥Îm{MÎmrbm XmoZ dVw©imH$ma Vi AgVmV.Vi Am{U ‘mWm Oo EH$‘oH$mbm EH$ê$n AgVmV.
H¥$Vr … Q>o~bmda EH$ d¥Îm{MÎmr R>odm Am{U EH$ n¥ð>mMm VwH$S>m Q>o~bmda g‘m§VaYabm Am{U Vmo d¥Îm{MÎmrÀ¶m darb ^mJmbm ñne© H$aVmo.
Oa Vwåhr nwÇ>m Am{U Q>o~bmMm darb ^mJ (d¥Îm{MÎmrMm Vi) ¶m‘Yrb b§~m§VaH$mT>bo, Va Vr d¥Îm{MÎmrMr C§Mr Amho.
AmVm Imbrb JwUY‘© Agboë¶m d¥Îm{MÎmrMm {dMma H$am. • ˶mbm XmoZ g‘m§Va Am{U EH$ê$n dVw©imH$ma Vi AgVmV.
• ˶mbm XmoZ Vim§À¶m H$S>m§Zm OmoS>Umao dH«$ n¥ð>^mJ AgVmV. • XmoZ Vim§À¶m ‘ܶmbm OmoS>Umam aofmI§S> hm Vimbm b§~ AgVmo. Vr d¥Îm{MÎmrMr C§Mr (h)
AgVo Am{U ˶mbm d¥Îm{MÎmrMm Aj Ago gwÕm åhUVmV.Aem d¥Îm{MÎmrbm b§~ dVw©imH$ma d¥Îm{MÎmr Ago åhUVmV. {Vbm Ago åhUVmV H$maUd¥Îm{MÎmrbm dVw©imH$ma Vi Am{U ˶mMm Aj hm Vimbm H$mQ>H$moZ AgVmo.¶m KQ>H$m‘ܶo Amåhr ’$º$ b§~ dVw©imH$ma d¥Îm{MÎmrer g§~§{YV Amho. VarnU doJù¶m àH$mao
{dMma Ho$bm Var gwÕm d¥Îm{MÎmr ¶m eãXmMm AW© b§~ dVw©imH$ma d¥Îm{MÎmr Amho.
d¥Îm{MÎmrMo dH«$n¥ð>’$i (Surface area of a cylinder)
Amåhmbm ‘m{hV Amho H$s, d¥Îm{MÎmr hr nmoH$i d¥Îm{MÎmr qH$dm ^ard d¥Îm{MÎmr ¶mn¡H$s EH$ Amho.’$º$ dH«$ n¥ð>^mJmZr nmoH$i d¥Îm{MÎmr V¶ma hmoVo. nmB©n, nmoH$i Zù¶m (straw) Zù¶m, ~mgar hr nmoH$i
d¥Îm{MÎmrMr CXmhaUo AmhoV.XmoZ dVw©imH$ma gnmQ> n¥ð>^mJ Am{U dH«$ n¥ð>^mJm§Zr ‘¶m©{XV Ho$boë¶m joÌmbm ^ard d¥Îm{MÎmr åhUVmV.d¥Îm{MÎmr Im§~, amoS> amobaMr MmHo$, ~mJoVrb amoba, nopÝgb, ^abobr d¥Îm{MÎmr Q>mH$s Am{U ^abobo H°$Z
(can) hr ^ard d¥Îm{MÎmrMr CXmhaUo AmhoV.d¥Îm{MÎmrÀ¶m n¥ð>^mJmMo joÌ’$i (XmoÝhr nmoH$i Am{U ard d¥Îm{MÎmr) ho d¥Îm{MÎmrÀ¶m ~mhoarb joÌ’$imer
g§~§{YV Amho.nmoH$i d¥Îm{MÎmrbm ’$º$ dH«$ n¥ð>’$i AgVo ˶mbm nmíd© n¥ð>’$i Agohr
åhUVmV. ¶m n¥ð>^mJmÀ¶m joÌ’$imbm dH«$ n¥ð>^mJmMo joÌ’$i (CSA) qH$dmnmoH$i d¥Îm{MÎmrÀ¶m nmíd© n¥ð>^mJmMo joÌ’$i (LSA) Amho.
^ard d¥Îm{MÎmrbm XmoZ dVw©imH$ma n¥ð>^mJ Am{U dH«$ n¥ð>’$i gwÕm AgVo.åhUyZ ^ard d¥Îm{MÎmrÀ¶m dH«$ n¥ð>^mJmMo joÌ’$i ho dH«$ qH$dm nmíd© n¥ð>^mJmMojoÌ’$i Amho.
^ard d¥Îm{MÎmrMo g§nyU© n¥ð>’$i ho XmoZ dVw©imH$ma joÌm§Mo joÌ’$i Am{U dH«$ n¥ð>’$i ¶m§Mr ~oarO Amho.AmVm, d¥Îm{MÎmrMo nmíd© n¥ð>’$i Am{U g§nyU© n¥ð>’$i H$mT>ʶmMo gyÌ aMy¶m.
h
Milk can Pipe Gas cylinder Pillars
Top circularbase
Bottom circular
darbdVw©imH$ma
dH«$ qH$dm nmíd©n¥ð>^mJ
ImbrbdVw©imH$ma Vi
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372 UNIT-15
i. d¥Îm{MÎmrMo dH«$ (nmíd©) n¥ð>’$i (Curved surface area of a cylinder)… {Xboë¶m d¥Îm{MÎmr modVr nyU©nUoJw§S>miUmam Am¶VmH¥$Vr H$mJX ¿¶m Am{U ˶m§Mr é§Xr hr d¥Îm{MÎmrÀ¶m C§Mrer g‘mZ Amho. nwR²>R>çm§Zr ~Z{dboë¶md¥Îm{MÎmr KodyZ gwÕm hr H¥$Vr Ho$br OmD$ eH$Vo. gai aofoda H$mnyZ nmíd© n¥ð> mJ CKS>bm Va Am¶V {‘iVmo.
b b
l
h
Fold
Cut
2 r
{ZarjU H$am H$s,Am¶VmH¥$Vr H$mJXmMo joÌ’$i = d¥Îm{MÎmrMo dH«$ n¥ð>’$iAm¶VmMr bm§~r = d¥Îm{MÎmrÀ¶m VimMm n[aK l = 2 rAm¶VmMr é§Xr = d¥Îm{MÎmrMr C§Mr b = hAmnë¶mbm ‘m{hV Amho H$s, Am¶VmMo joÌ’$i = l × b = 2 r × h = 2 rh
d¥Îm{MÎmrMo dH«$ (nmíd©) n¥ð>’$i = 2 rh Mm¡. EH$H$
ii. ^ard d¥Îm{MÎmrMo g§nyU© n¥ð>’$i (Total surface area of a solid cylinder) …
d¥Îm{MÎmrMo g§nyU© n¥ð>’$i = 2 r (h + r) Mm¡. EH$H$
d¥Îm{MÎmrMo KZ’$i (Volume of a cylinder)Vwåhr nyduM Aä¶mgbobo Amho H$s, bmobH$mMo KZ’$i ho ˶m§À¶m VimMo joÌ’$i Am{U C§Mr ¶m§Mm JwUmH$ma Amho.Á¶mAWu d¥Îm{MÎmr hr gwÕm dVw©imH$ma VimMm bmobH$ Amho, {VMo KZ’$i gwÕm gma»¶mM nÕVrZo H$mT>bo OmVo.
(i) ^ard d¥Îm{MÎmrMo KZ’$i (Volume of a solid cylinder) :
^ard d¥Îm{MÎmrMo KZ’$i = VimMo joÌ’$i × C§Mr = r2 × h = r2h
d¥Îm{MÎmrMo KZ’$i = r2h KZ EH$H$
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaUo 1 … b§~ dVw©imH$ma d¥Îm{MÎmrMo dH«$ n¥ð>’$i (CSA) H$mT>m Á¶mMr C§Mr Am{U {ÌÁ¶m AZwH«$‘o 30g|.‘r. Am{U 3.5 g|.‘r. Amho.CH$b … d¥Îm{MÎmrMo dH«$ n¥ð>’$i = 2 rh =
222
73.5
0.5cm×30cm CSA = 660 Mm¡.g|.‘r.
h
r
A = r2
d¥Îm{MÎmrMo dH«$n¥ð>’$i
dVw©imH$ma VimMojoÌ’$i
d¥Îm{MÎmrMo g§nyU©n¥ð>’$i = + 2 ×
= 2 rh + 2 × r2
= 2 r (h + r)
KS>r
H$mn
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Mensuration 373
CXmhaUo 2 … EH$m b§~ dVw©imH$ma d¥Îm{MÎmrMo dH«$ n¥ð>’$i 88 Mm¡.g|.‘r. Am{U C§Mr 14 g|.‘r. Amho. Vad¥Îm{MÎmrÀ¶m VimMr {ÌÁ¶m H$mT>m.CH$b … d¥Îm{MÎmrMo dH«$n¥ð>’$i = 2 rh = 88 Mm¡.g|.‘r.=
222 14cm7
r
r =1 2 4 88 2cm 7
2 22 14 2cm = 1 g|.‘r. d¥Îm{MÎmrÀ¶m VimMr {ÌÁ¶m = 1 g|.‘r.
CXmhaU 3 … XmoZ b§~ dVw©imH$ma d¥Îm{MÎmrÀ¶m {ÌÁ¶|Mo JwUmoÎma 2…3 Am{U ˶m§À¶m C§MrMo JwUmoÎma 5…4 Amho. Va˶m§À¶m dH«$ n¥ð>’$im§Mo JwUmoÎma H$mT>m.
CH$b … XmoZ d¥Îm{MÎmtÀ¶m {ÌÁ¶m AZwH«$‘o 2r d 3r Am{U ˶m§Mr C§Mr AZwH«$‘o 5h Am{U 4h AmhoV Ago ‘mZy.S1 Am{U S2 ho XmoZ d¥Îm{MÎmtMo dH«$ n¥ð>’$i Amho Ago ‘mZy.S1 {ÌÁ¶m 2r Am{U C§Mr 5h AgUmè¶m d¥Îm{MÎmrMo dH«$ n¥ð>’$i = S1 = 2 × × 2r × 5h = 20 rhS2 {ÌÁ¶m 3r Am{U C§Mr 5h AgUmè¶m d¥Îm{MÎmrMo dH«$ n¥ð>’$i = S2= 2 × × 3r × 4h = 24 rh
1
2
SS =
5 206 24
rh 56rh
S1 : S2 = 5 : 6
CXmhaU 4 … 120 g|.‘r. bm§~ amobaMm ì¶mg 84 g|.‘r. Amho. H«$sS>m§JUmMo gnmQ>rH$aU H$aʶmgmR>r ˶mZo 500’o$è¶m nyU© Ho$ë¶m Va 2.50 n¡go Xa Mm¡ag ‘r à‘mUo gnmQ>rH$aU H$aʶmg ¶oUmam IM© H$mT>m.CH$b … h = 120 g|.‘r. r = 42 g|.‘r.
EH$m ’o$ar‘ܶo amobaZo AmH«${‘bobo joÌ’$i = amobaMo dH«$ n¥ð>’$i = 2 rh
=22
27
426cm × 120cm
500 Mo ’o$è¶m‘ܶo AH«${‘bobo joÌ’$i = (31,680 × 500) Mm¡.g|.‘r. = 15,84,000 Mm¡.g|.‘r.
‘rQ>a‘ܶo ì¶mnbobo joÌ’$i = 215840000 m100 100
= 1584 ‘r2
Xa Mm¡ag ‘rQ>a‘ܶo {H«$S>m§JUmÀ¶m gnmQ>rH$aUmg ¶oUmam IM© = 2.50 ps
{H«$S>m§JUmÀ¶m gnmQ>rH$aUmg ¶oUmam IM© = 1584 m2 × 2.50 n¡go/‘r2 = < 3936
CXmhaU 5 … YmVwMr nmB©n 77 g|.‘r. bm§~ Amho. Cä¶m N>oXmMm {ÌÁ¶m 4 g|.‘r. Amho. ~mhoarb {ÌÁ¶m 4.4g|.‘r. Amho. Va (a) AmVrb dH«$ n¥ð>’$i (b) ~mhoarb dH«$ n¥ð>’$i (c) g§nyU© n¥ð>’$i H$mT>m.CH$b … ~mhoarb {ÌÁ¶m = R = 2.2 g|.‘r.; AmVrb {ÌÁ¶m = r = 2 g|.‘r.; h = 77 g|.‘r.
(a) AmVrb dH«$n¥ð>’$i (CSA) = S1 = 2 rh =22
27
2cm 7711
cm = 968 Mm¡.g|.‘r.(b) ~mhoarb dH«$n¥ð>’$i (CSA) = S2 = 2 Rh =
222
72.2cm 77
11cmg|.‘r. = 1064.8 Mm¡.g|.‘r.
(c) g§nyU© n¥ð>’$i (TSA) = S1 + S2 + XmoZ VimMo joÌ’$i = S1 + S2 + 2( R2 – r2)
= 968Mm¡.g|.‘r. + 1064.8Mm¡.g|.‘r. +22
27 {(2.2)2 – 22}
=44968 1064.87
0.840.12
Mm¡.g|.‘r.
= (968 + 1064.8 + 5.28) Mm¡.g|.‘r. TSA = 2038.08 Mm¡.g|.‘r.
CXmhaU 6 … Oa VimMr {ÌÁ¶m 7 g|.‘r. Am{U C§Mr 15 g|.‘r. Agob Va b§~ dVw©imH$ma d¥Îm{MÎmrMo KZ’$i
H$mT>m.
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374 UNIT-15
CH$b … r = 7 g|.‘r., h = 15 g|.‘r.
d¥Îm{MÎmrMo KZ’$i = r2h =227
7cm × 7cm × 15cm
KZ’$i = 2310 K.g|.‘r.
CXmhaU 7 … d¥Îm{MÎmrÀ¶m VimMm n[aK 132 g|.‘r. Am{U ˶mMr C §Mr 25 g|.‘r. Amho Va d¥Îm{MÎmrMo
KZ’$i H$mT>m.
CH$b …'r' hr d¥Îm{MÎmrMr {ÌÁ¶m Amho Ago g‘Oy.
n[aK = 132 g|.‘r.
2 r = 132 g|.‘r.2227
r = 132 g|.‘r.
r =132
6 3
cm 72 22
r = 21 g|.‘r.
dÎm{MÎmrMo KZ’$i = r2 h = 222 (21cm) 25cm7
=227
213
21 25cmK.g|.‘r.= 34,650 K.g|.‘r.
CXmhaU 8 … 14 g|.‘r. bm§~ YmVyÀ¶m d¥Îm{MÎmr AmH$mamÀ¶m nmB©nÀ¶m ~mhoarb Am{U AmVrb n¥ð>^mJmÀ¶m
joÌ’$imVrb ’$aH$ 44 Mm¡.g|.‘r. Amho. Oa nmB©n 99 K.g|.‘r. À¶m YmVynmgyZ ~Z{dbm Amho. Va nmB©nmMr
~mhoarb Am{U AmVrb {ÌÁ¶m H$mT>m.
CH$b … R hr ~mhoarb {ÌÁ¶m Am{U 'r' hr YmVyÀ¶m nmB©nMr AmVrb {ÌÁ¶m ‘mZy h = 14 g|.‘r.
~mhoarb n¥ð>^mJmMo joÌ’$i – AmVrb n¥ð>^mJmMo joÌ’$i = 44 Mm¡.g|.‘r.
2 Rh – 2 rh = 44 Mm¡.g|.‘r. R – r= 44222 147
= 2 44 72 22 14 2
R – r =12
dmnaboë¶m YmVyMo KZ’$i = 99 K.g|.‘r.~mhoarb KZ’$i – AmVrb KZ’$i = 99 K.g|.‘r.
R2h – r2h = 99 K.g|.‘r.
h(R2 – r2) = 99 K.g|.‘r.227
142(R r)(R r)= 99 K.g|.‘r. [ a2 – b2 = (a + b)(a – b)] Am{U 1R r 2
22 2 1cm(R r)2 = 99 K.g|.‘r. R + r=
999
22 =92
R r 92
R r 12
102R 2
R + r = 92
2R = 5 r + 2.5 = 4.5
g|.‘r. 7
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Mensuration 375
R = 52 = 2.5 g|.‘r. r= 4.5 – 2.5 = 2 g|.‘r.
~mhoarb {ÌÁ¶m = 2.5 g|.‘r.; AmVrb {ÌÁ¶m = 2 g|.‘r.
CXmhaU 9 … d¥Îm{MÎmr AmH$mamÀ¶m ^m§S>çmMm VimMm n[aK 132 g|.‘r. Am{U ˶mMr C§Mr 25 g|.‘r. Amho.
˶m‘ܶo g‘mdbobo nmUr {H$Vr {bQ>a Amho.
CH$b … n[aK C= 132 g|.‘r. , h = 25 g|.‘r. VimMr {ÌÁ¶m = r ‘mZy
n[aK = 132 g|.‘r. 2 r = 132 g|.‘r.22
2 r7
= 132 g|.‘r.
r=132
2227
=132
6 3
72 22 r = 21 g|.‘r.
^m§S>çmMo KZ’$i = r2h= 2 322 (21) 25cm7
K.g|.‘r.=227
213
21 25 cmK.g|.‘r.= 34650 K.g|.‘r.
KZ’$i {bQ>a‘ܶo =346501000
[ 1000 K.g|.‘r. = 1 {bQ>a] = 34.65 {bQ>a
^m§S>çm‘ܶo 34.65 {bQ>a BVHo$ nmUr Amho.CXmhaU 10 … Oa b§~ dVw©imH$ma d¥Îm{MÎmrÀ¶m VimÀ¶m {ÌÁ¶oMo XmoZ AY© mJ AmhoV. ˶m§Mr C§Mr g‘mZ AmhoZdrZ d¥Îm{MÎmrÀ¶m KZ’$imMo ‘wi d¥Îm{MÎmrÀ¶m KZ’$imer JwUmoÎma {H$Vr?
CH$b … Oa V1 ho ‘wi d¥Îm{MÎmrMo KZ’$i Am{U V2 ho ZdrZ d¥Îm{MÎmrMo KZ’$i Amho Ago ‘mZy,
‘yi d¥Îm{MÎmrMr {ÌÁ¶m = r ZdrZ d¥Îm{MÎmrMr {ÌÁ¶m = 2r
V1= r2h Am{U V2 =2r h
21
2
VV =
2r h2r h4
= 2
1
V4 11 V 4
V2 : V1 = 1 : 4
CXmhaU 11 ^ard d¥Îm{MÎmrMo g§nyU© n¥ð>’$i (TSA) 462 Mm¡.go.‘r. Amho. ˶mMo dH«$ n¥ð>’$i (CSA) ho g§nyU©
n¥ð>’$imÀ¶m (TSA) À¶m EH$ V¥Vr¶Am§e Amho. Va d¥Îm{MÎmrMo KZ’$i H$mT>m.
CH$b …d¥Îm{MÎmrMo dH«$ n¥ð>’$i (CSA) =13
d¥Îm{MÎmrMo g§nyU© n¥ð>’$i (TSA)
2 rh =13
× 2 r (h + r) =13
462154
cmMm¡.g|.‘r.
2 rh = 154 Mm¡.g|.‘r.
(TSA) d¥Îm{MÎmrMo g§nyU© n¥ð>’$i = 2 r (h + r)
462 Mm¡.g|.‘r. = 2 rh + 2 r2 = 154 Mm¡.g|.‘r. + 2 r2
462 Mm¡.g|.‘r. – 154 Mm¡.g|.‘r.= 2 r2 308 Mm¡.g|.‘r. = 22227
r 30814 7
72 22
= r2
r2 = 49 r = 7 g|.‘r.
d¥Îm{MÎmrMo dH«$ n¥ð>’$i (CSA) = 154 Mm¡.g|.‘r.
2 rh = 154 Mm¡.g|.‘r.22
27
7cm h = 154 Mm¡.g|.‘r. h =154
7
442 =
72 g|.‘r.
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376 UNIT-15
d¥Îm{MÎmrMo KZ’$i = r2h = 2 322 77 cm7 2 Mm¡.g|.‘r. =
11 227
7492 Mm¡.g|.‘r. = 539 K.g|.‘r.
ñdmܶm¶ 15.1
1. b§~ dVw©imH$ma d¥Îm{MÎmrMr C§Mr 14 g|.‘r. Am{U VimMr {ÌÁ¶m 2 g|.‘r. Amho Va ˶mMo (i) CSA(ii) TSA H$mT>m.
2. 20 g|.‘r. bm§~rÀ¶m bmoI§S>r nmB©nMr ~mhoarb {ÌÁ¶m 12.5 g|.‘r. Am{U AmVrb {ÌÁ¶m 11.5 g|.‘r.Amho. Va nmB©nMo g§nyU© n¥ð>’$i (TSA) H$mT>m.
3. XmoZ b§~ dVw©imH$ma d¥Îm{MÎmtÀ¶m {ÌÁ¶oMo JwUmoÎma 2…3 Am{U ˶m§À¶m dH«$ n¥ð>^mJm§Mo JwUmoÎma 5…6 Amho.Va ˶m§À¶m C§MrMo JwUmoÎma H$mT>m.
4. dVw©imH$ma {d{harMm AmVrb ì¶mg 2.8 ‘r Amho. {VMr Imobr 10 ‘r. Amho Va ˶mMo dH«$ n¥ð>’$iH$mT>m. ¶m dH«$ n¥ð>^mJmbm {Jbmdm H$aʶmgmR>r é.42 Xa Mm¡.‘r. à‘mUo ¶oUmam IM© gwÕm H$mT>m.
5. emioVrb H«$mâQ> {ejH$mZo nwR²>R>çmnmgyZ d¥Îm{MÎmrÀ¶m AmH$mamMo noZ R>odm¶Mo gmYZ H$am¶Mo {dÚm϶mªZm{eH${dbo. emioVrb {dÚm϶mªMr g§»¶m 42 Amho, Oa à˶oH$ 5 g|.‘r. {ÌÁ¶m Am{U 14 g|.‘r. C§MrMonoZ R>odm¶Mo gmYZ V¶ma Ho$bo. Va ˶m§Zr dmnabobm nwÇ>m {H$Vr?
6. 1.4 ‘r. ì¶mgmÀ¶m ~mJoVrb amobaMr bm§~r 2 ‘r. Amho. Va 5 ’o$è¶m‘ܶo ˶mZo AmH«${‘bobo A§Va{H$Vr?
7. {ÌÁ¶m 10.5 g|.‘r. Am{U C§Mr 16 g|.‘r. AgUmè¶m b§~ dVw©imH$ma d¥Îm{MÎmrMo KZ’$i H$mT>m.8. d¥Îm{MÎmr AmH$mamÀ¶m bmH$S>r nmB©nMm AmVrb ì¶mg 24 g|.‘r. Am{U ~mhoarb ì¶mg 28 g|.‘r. Amho.
nmB©nMr bm§~r 35 g|.‘r. Amho. Oa 1 K.g|.‘r.Mo dOZ 0.6 J«°‘ Amho Va nmB©nMo dOZ H$mT>m.9. g‘mZ KZ’$imÀ¶m XmoZ dVw©imH$ma d¥Îm{MÎmtÀ¶m C§MrMo JwUmoÎma 1…2 Amho Va ˶m§À¶m {ÌÁ¶oMo JwUmoÎma
H$mT>m.10. 44 g|.‘r. × 20 g|.‘r. AmH$mamMm Am¶VmH¥$Vr H$mJX ˶mÀ¶m bm§~r‘ܶo Jw§S>miyZ d¥Îm{MÎmr ~Z{dbr.
Va V¶ma Pmboë¶m d¥Îm{MÎmrMo KZ’$i H$mT>m.e§Hy$ (Cone)Imbrb dñVy§Mo {ZarjU H$am.
˶m e§Hy$À¶m AmH$mamÀ¶m AmhoV. Vo nmoH$iqH$dm ^ard Agy eH$VmV.
{ZarjU H$am H$s e§Hy$Mm Vi dVw©imH$maAm{U dH«$ n¥ð >’$i VimnmgyZ {Z‘wiVo hmodyZ{eamoq~XÿV {‘iVmo.
e§Hy§$Mr VwbZm {na°{‘S> (gwMr)er H$am.e§Hy$ ho dVw©imH$ma VimMo {na°{‘S>Mo àH$ma AmhoV.
e§Hy$ ¶m ^ard dñVy AmhoV ˶m gnmQ> dVw©imH$ma Vi {Z‘wiVm hmodyZ EH$mq~XÿV {‘iVmo ˶mbm {eamo q~Xÿ Ago åhUVmV.
b§~ dVw©imH$ma e§Hy$Mm nm¶m dVw©imH$ma AgyZ ˶mMm Aj nm¶mÀ¶m ‘ܶmVyZOmVmo Am{U nm¶mbm b§~ AgVmo.
AmB©pñH«$‘MmH$moZ
dmT>{XdgmMrQ>monr
KamMo N>ßna dmiyMr amg
e§Hy$ {na°{‘S>Cone Pyramid
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Mensuration 377
H¥$Vr … EH$ OmS> H$mJX ¿¶m Am{U B = 900 Agbobm H$mQ>H$moZ {ÌH$moU ABC H$mnm. AB À¶m b§~ ~mOybm EH$bm§~ Xmoam {MH$Q>{dbm Ago g‘Oy. {ÌH$moUmÀ¶m XmoÝhr ~mOyMmXmoam hmVmV Yam Am{U {ÌH$moU Xmoè¶m^modVr {’$adm.
V¶ma Pmbobm AmH$ma Vwåhr AmoiIy eH$mb H$m?
V¶ma Pmbobm AmH$ma b§~ dVw©imH$ma e§Hy$Mm Amho.åhUyZ AmnU Agm {ZîH$f© H$mTy> H$s,
Oa H$mQ>H$moZ Agbobr EH$ ~mOy pñWa R>odyZ ˶m ^modVr H$mQ>H$moZ {ÌH$moU {’$a{dë¶mZo {Z‘m©U hmoUmè¶mKZmH¥$Vrbm e§Hy$ Ago åhUVmV.e§Hy$À¶m AmH¥$VrMo {ZarjU H$am.
• AB Mr bm§~r qH$dm dVw©imH$ma VimMm ‘ܶ q~XÿnmgyZ {eamoq~Xÿ n¶ªVÀ¶m A§Vambme§Hy$Mr C§Mr (AB=h) Ago åhUVmV. ˶mbm e§Hy$Mm Aj Agohr åhUVmV.
• BC Mr bm§~r VimMr {ÌÁ¶m Amho. (BC = r)
• AC Mr bm§~r qH$dm {eamoq~XÿnmgyZ dVw©imH$ma Vimdarb H$moUVmhr q~Xþ ¶m‘YrbA§Vambm e§Hy$Mr {VaH$g C§Mr (l) Ago åhUVmV. (AC = AD = l)
e§Hy$Mr {VaH$g C§Mr (l) Am{U C§Mr (h) ¶m‘ܶo H$moUVmhr g§~§Y Amho H$m?AmH¥$Vr‘Yrb ABC ¶m H$mQ>H$moZ {ÌH$moUmMm {dMma H$am.
AC2= AB2 + BC2 (nm¶W°JmoagÀ¶m à‘o¶mdê$Z) l2 = h2 + r2
OoWo 'l' hr {VaH$g C§Mr, h hr C§Mr, r hr e§Hy$À¶m VimMr {ÌÁ¶m Amho.
l = 2 2h r , h = 2 2l r , qH$dm r = 2 2l h
AmVm Imbrb JwUY‘© Agboë¶m e§Hy$Mm {dMma H$am.• ˶mbm dVw©imH$ma nmVir hm Vi Amho.• e§Hy$Mm Aj Am{U {VaH$g C§Mr N>oXUmè¶m q~Xÿbm {eamoq~Xÿ åhUVmV.• ˶mbm dH«$ n¥ð>’$i Amho Oo dVw©imH$ma VimMr H$S>m Am{U {eamoq~Xÿ ¶m§Zm OmoS>Vo.• {eamoq~Xÿ Am{U dVw©imH$ma VimMm ‘ܶ ¶m§Zm OmoS>Umar aofm Vimbm b§~ AgVo.
Aem àH$maÀ¶m e§Hy$bm b§~ dVw©imH$ma e§Hy$ Ago åhUVmV. d¥Îm{MÎmrà‘mUo Á¶mAWu AmnU ’$º$ b§~dVw©imH$ma e§Hy$Mm Aä¶mg H$aVmo Voìhm ¶m KQ>H$m‘ܶo e§Hy$ åhUOoM b§~ dVw©imH$ma e§Hy$ Agm hmoVmo.
e§Hy$Mo dH«$ n¥ð>’$i Surface area of a cone
e§Hy$À¶m n¥ð>^mJm‘ܶo dH«$ n¥ð>^mJ Amho Vmo dVw©imÀ¶mdibobm ^mJ Am{U dVw©imH$ma VimZo ~Zbobm Amho. Omo{d^mJ e§Hy$Mo joÌ ~Z{dVmo ˶mbm dH«$ n¥ð>’$i qH$dm e§Hy$Monmíd©n¥ð>’$i Ago åhUVmV.
Imbrb AmH¥$˶m§Mo {ZarjU H$am …
A
BC
A
BC DB
CD
A
A
B CD
h l
{d^mJ … {ÌÁ¶m Am{U H§$g ¶m§Zr ‘¶m©XrVHo$bobm dVw©imH$ma joÌmMm ^mJ.
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378 UNIT-15
hl ll
2 r
Oa nwR²>R>çmMm dVw©imH$ma e§Hy$Mm Vi ~§X Ho$bm Va dH«$n¥ð>’$i Am{U dVw©imH$ma VimMo joÌ’$i ¶m§Mr ~oarOHo$br Va e§Hy$Mo g§nyU© n¥ð>’$i ¶oVo.
i. e§Hy$Mo dH«$ n¥ð>’$i (Curved surface area of cone)
Oa nwR²>R>çmnmgyZ ~Z{dbobm e§Hy$ H$mnbmAm{U ngabm Va Imbr XmI{dë¶mà‘mUo{d^mJ {‘iVmo.
{d^mJmMo joÌ’$i ho e§Hy$Mo dH«$ n¥ð>’$iAmho.
{d^mJmMo joÌ’$i H$go H$mT>bo OmVo?
'r' hr e§Hy$Mr {ÌÁ¶m Amho Ago ‘mZy. 'l ' hr e§Hy$Mr {VaH$g C§Mr Amho.
' ' hm {d^mJmMm H|$Ðr¶ H$moZ Amho.
¶oWo {d^mJmMr {ÌÁ¶m 'r' hr e§Hy$À¶m {VaH$g C§Mr BVH$sM
Amho. r = l
{d^mJmMo joÌ’$i =2
360l .........(1)
{d^mJmÀ¶m H§$gmMr bm§~r 'L' ‘mZy.
Voìhm,2 360lL
.
H§$gmMr bm§~r 'L' =360
2 l ......................(2)
AmH¥$Vr‘ܶo,
{d^mJmÀ¶m H§$gmMr bm§~r = e§Hy$À¶m dVw©imH$ma VimMm n[aK
L = 2 r ....................................................(3)
(2) Am{U (3) dê$Z Amåhmbm {‘iob 2 r =3602 l
rl
=360
{d^mJmMo joÌ’$i 'A' ‘mZy.2l
A=
360
A= 2
360l = 2 r
ll
= rl
e§Hy$Mo dH«$ n¥ð>’$i = rl Mm¡. EH$H$
Á¶mAWu rl ho 12
2rl Ago {b{hVmV Am{U 2 r hm e§Hy$À¶m VimMm n[aK Amho, 'l' hr {VaH$g C§Mr
Amho. Amåhmbm {‘iVo,e§Hy$Mo dH«$ n¥ð>’$i = e§Hy$À¶m VimMm n[aK × {VaH$g C§Mr
hl l
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Mensuration 379
e§Hy$Mo dH«$ n¥ð>’$i (CSA) ho e§Hy$À¶m VimMm n[aK (2 r) Am{U {VaH$g C§Mr (l) ¶m§À¶m JwUmH$mamÀ¶m{Zå‘o AgVo.
(ii)^ard b§~ dVw©imH$ma e§Hy$Mo g§nyU© n¥ð>’$i (Surface area of a hollow cone)
e§Hy$Mo g§nyU© n¥ð>’$i = e§Hy$À¶m dH«$ n¥ð>’$i = VimMo joÌ’$i
= rl + r2
= r (l + r)
e§Hy$Mo g§nyU© n¥ð>’$i = r (l + r) Mm¡ag EH$H$
e§Hy$Mo KZ’$i (Volume of cone)e§Hy$Mo KZ’$i H$mT>ʶmgmR>r Ho$boë¶m à¶moJmMm {dMma H$am. à¶moJmMm Aä¶mg H$am Am{U bhmZ JQ>mV
nwÝhm-nwÝhm H$am.
EH$ Vi ~§X Agbobr nmoH$i d¥Îm{MÎmr Am{U g‘mZ nm¶md {VaH$g C§MrMm nmoH$i e§Hy$ ¿¶m. Oa Vo nmaXe©H$ dñVynmgyZ~Zbobo AgVrb Va A˶§V Cn¶wº$ hmoVo. ˶m§Mr OmS>r e³¶ {VVH$sH$‘r Agmdr.
ghOnUo {ÌÁ¶m Am{U C§Mr VnmgVm ¶oUmè¶m AmH¥$˶m§Mo{ZarjU H$am.
e§Hy$‘ܶo nmUr qH$dm dmiy ^ê$Z Vr d¥Îm{MÎmr‘ܶo AmoVm. e§Hy$‘ܶo VrZ doim nmUr qH$dm dmiy ^ê$Zd¥Îm{MÎmr‘ܶo AmoVbr AgVm Vr nyU©nUo ^aVo.
Amåhmbm ‘mhrV Amho H$s, d¥Îm{MÎmrMo KZ’$i = r2h OoWo 'r' hr ˶mÀ¶m dVw©imH$ma VimMr {ÌÁ¶mAm{U 'h' C§Mr Amho.
darb à¶moJmdê$Z AmnU H$gm {ZîH$f© H$mTy> H$s,
e§Hy$Mo KZ’$i =13
× d¥Îm{MÎmrMo KZ’$i
e§Hy$Mo KZ’$i =13 r2 h KZ EH$H$
AmVmn¶ªV Amåhr d¥Îm{MÎmr Am{U e§Hy$ ¶m§Mo joÌ’$i Am{U KZ’$i ¶m§Mm Aä¶mg Ho$bobm Amho.d¥Îm{MÎmr Am{U e§Hy$ ¶m§Mm joÌ’$i Am{U KZ’$i‘Yrb ~Xb ‘Ooera Amho, Oa ˶m§Mr {ÌÁ¶m C§Mr XþßnQ>qH$dm AmYu Ho$br AgVm. Imbrb H$moï>H$mMm Aä¶mg H$am.
rl
r2
12
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380 UNIT-15
A. KZnXmW© d¥Îm{MÎmr e§Hy$
Z§. nmíd©n¥ð>’$i g§nyU© n¥ð>’$i KZ’$i KZ’$iLSA TSA V V
1.whenr = h 2 r2 4 r2 r3
13
r3
2.r 2rh h 4 rh 4 r(2r + h) 4 r2h
43
r2h
3.r rh 2h 4 rh 2 r(r + 2h) 2 r2h
23
r2h
4.r2r
h hrh
rr h2
2r h4
2r h12
5. h2
rh
rrh
h2 r r2
2r h2
2r h6
6.r2
h2
rh
rh2
r hr2 2
2r h8
2r h12
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1 … e§Hy$Mm ì¶mg 14 g|.‘r. Am{U {VaH$g C§Mr 10 g|.‘r. Amho. Va ˶mMo dH«$ n¥ð>’$i H$mT>m.
CH$b … d= 14 g|.‘r. r =142 = 7 g|.‘r., l = 10 g|.‘r.
e§Hy$Mo dH«$ n¥ð>’$i = rl =227
7´ cm 10cm´ = 220 Mm¡.g|.‘r.
CXmhaU 2 … VimMr {ÌÁ¶m 14 ‘r. Am{U {VaH$g C§Mr 9 ‘r. AgUmè¶m e§Hy$Mo g§nyU© n¥ð>’$i H$mT>m.
CH$b … l = 9 ‘r., r = 14 ‘r.
e§Hy$Mo g§nyU© n¥ð>’$i = r (r + l ) =227
142m (14 9) m‘r. =
227
142
23 mMm¡.‘r.
e§Hy$Mo g§nyU© n¥ð>’$i = 1012 Mm¡.‘r.
CXmhaU 3 … VimMr {ÌÁ¶m 7 ‘r. Am{U C§Mr 24 ‘r. AgUmè¶m e§Hy$À¶m AmH$mamMm V§~y ~Z{dʶmgmR>r 5 ‘r.é§XrMo {H$Vr ‘r. H$mnS> bmJob.
CH$b …r = 7 ‘r, h = 24 ‘r, l = ?
l2 = r2 + h2 = 72 + 242 = 49 + 576 = 625 l = 625 = 25 ‘r.
dmnaboë¶m H$nS>çmMo joÌ’$i = e§Hy$À¶m AmH$mamÀ¶m V§~yMo dH«$ n¥ð>’$i (CSA)
e§Hy$Mo dH«$ n¥ð>’$i = rl =227
7m 25m 550 Mm¡.‘r.
H$nS>çmMo joÌ’$i = 550 Mm¡.‘r.
bm§~r × é§Xr = 550 Mm¡.‘r.
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Mensuration 381
bm§~r =550
ê§$XrMm¡.‘r =
g|.‘r5505
110 ‘r.
dmnaboë¶m H$nS>çmMr bm§~r = 110 ‘r.
CXmhaU 4 … e§Hy$Mo dH«$ n¥ð>’$i CSA 4070 Mm¡.g|.‘r. Am{U ì¶mg 70 g|.‘r. Amho. Va {VaH$g C§Mr {H$Vr?
CH$b … d = 70 g|.‘r. r = 35 g|.‘r.
e§Hy$Mo dH«$ n¥ð>’$i = rl.
4070 Mm¡.g|.‘r. =227
355cmg|.‘r.x l
37 407 011 0 = l l = 37 g|.‘r.
e§Hy$Mo dH«$ n¥ð>’$i = 37 g|.‘r.
CXmhaU 5 … e§Hy$À¶m AmH$mamÀ¶m H$igmMr {VaH$g C§Mr Am{U VimMm ì¶mg AZwH«$‘o 25 ‘r. Am{U 14 ‘r.Amho. ˶mÀ¶m dH«$ n¥ð>^mJmbm nm§T>am a§J bmdʶmgmR>r é.210 à˶oH$ 100 Mm¡.‘r. à‘mUo {H$Vr IM© ¶oVmo?
CH$b … l = 25 ‘r., d= 14 ‘r. r =142 = 7 ‘r. e§Hy$Mo dH«$ n¥ð>’$i = rl =
227
7 25227
7 25 ‘ r‘ r
e§Hy$À¶m AmH$mamÀ¶m H$igmMo dH«$ n¥ð>’$i CSA = 550 Mm¡.‘r.100 Mm¡.‘r.bm nm§T>am a§J bmdʶmgmR>r ¶oUma IM© = < 210
550 Mm¡.‘r.bm nm§T>am a§J bmdʶmgmR>r ¶oUmam IM© =210`
10 0 255 0
m = < 1155
CXmhaU 6 … XmoZ e§Hy$Mm ì¶mg g‘mZ Amho. Oa ˶m§À¶m {VaH$g C§MrMo JwUmoÎma 5…4 Amho Va ˶m§À¶m dH«$n¥ð>’$imMo (CSA) joÌ’$i H$mT>m.CH$b …n{hë¶m e§Hy$Mo dH«$ n¥ð>’$i S1 Am{U Xþgè¶m e§Hy$Mo dH«$ n¥ð>’$i S2 ‘mZy.
˶m§Mr {VaH$g C§Mr AZwH«$‘o 5l Am{U 4l Amho Ago ‘mZy. e§Hy$Mo dH«$ n¥ð>’$i (CSA) = rl
1
2
SS =
r 5lr 4l S1 : S2 = 5 : 4
CXmhaU 7 …e§Hy$Mr {ÌÁ¶m 10 g|.‘r. Am{U {VaH$g C§Mr 26 g|.‘r. Amho Va KZ’$i H$mT>m.
CH$b … {ÌÁ¶m = 10 g|.‘r., l = 26 g|.‘r.V= ? h=?
C§Mr g |.‘ r22h= l r 56 100 77 242
262
10 66
KZ’$i v = 2 hr13
= 13
227 × 10 × 10 × 24
= 2512 K. g|.‘r.
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382 UNIT-15
CXmhaU 8… 24 g|.‘r. C§Mr AgUmè¶m e§Hy$Mo dH«$ n¥ð>’$i 550 Mm¡.g|.‘r. Amho. Va ˶mMo KZ’$i H$mT>m.CH$b … h = 24 g|.‘r. e§Hy$Mo dH«$ n¥ð>’$i = 550 Mm¡.g|.‘r.
Amåhmbm ‘mhrV Amho H$s, l2 = r2 + h2 = r2 + 242 = r2 + 576 l = 2r 576+e§Hy$Mo dH«$ n¥ð>’$i (CSA) = 550 Mm¡.‘r. rl = 550
222r r 576
7 = 550 2r r 576 =
55025
722
2r r 576 = 175
XmoÝhr ~mOyMm dJ© H$ê$Z2
2r r 576 = (175)2 r2 (r2 + 576) = 30625
r4 + 576r2– 30625 = 0 r4 + 625r2– 49r2 + 30625 = 0
r2(r2 + 625) – 49(r2 + 625) = 0 (r2 + 625) (r2 – 49) = 0
If r2 – 49 = 0 r2 = 49
r = 49 r = 7 g|.‘r.
e§Hy$Mo KZ’$i = 21 r h3
=13
227
7 7 248
K.g|.‘r. e§Hy$Mo KZ’$i = 1232 K.g|.‘r.
CXmhaU 9 … e§Hy$À¶m AmH$mamMm H$mMoMm M§~y nmʶmZo ^abobm Amho. M§~yÀ¶m VimMr {ÌÁ¶m 3 g|.‘r. Am{UC§Mr 15 g|.‘r. Amho. Vo nmUr ~§X Vi Agboë¶m g‘mZ {ÌÁ¶m 1.5 g|.‘r. Agboë¶m d¥Îm{MÎmr AmH$mamÀ¶mH$mMoÀ¶m ZirV AmoVbo. Va H$mMoÀ¶m ZirVrb nmʶmMr C§Mr H$mT>m.
CH$b … e §H y $‘Yrb nmʶmM o KZ’$i = d ¥Îm{MÎmr‘Yrb nmʶmM o KZ’$i 2c
1r h
3 c = 2cyr hcy
31 22 3 3 15cm3 7
= cy22 1.5 1.5 h7
hcy=
13
227
32
32
155
227
1.5 1.5hcy= 20 g|.‘r.
H$mMoÀ¶m Zir‘Yrb nmʶmMr C§Mr = 20 g|.‘r.
CXmhaU 10 … 1.8 ‘r. C§M Am{U VimMm ì¶mg 2 ‘r. Agbobr YmVyMr ^ard d¥Îm{MÎmr {dVidyZ 3 ‘r.ì¶mgmÀ¶m b§~ dVw©imH$ma e§Hy$‘ܶo nwZ…{Z©‘mU Ho$br. Va e§Hy$Mr C§Mr H$mT>m?
CH$b … d¥Îm{MÎmrMr C§Mr h= 1.8 ‘r., d = 2‘r. r =22 = 1‘r. e§Hy$Mm ì¶mg d = 3‘r., r =
32 = 1.5 ‘r., h = ?
e§Hy$Mo KZ’$i = d¥Îm{MÎmrMo KZ’$i 2cyr hcy = 2
c1
r h3 c
22 1 1 1.8m7
K.‘r. =1 22 1.5 1 m3 7 ch K.‘r.
hc =
227
1 1 1.8
1 223 7
1.5 1.5=
1.86
32
1.5 6 1.5=
125
hC = 2.4,
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Mensuration 383
e§Hy$Mr C§Mr = 2.4 ‘r.
ñdmܶm¶ 15.2
1. {VaH$g C§Mr 60 g|.‘r. Am{U VimMr {ÌÁ¶m 21 g|.‘r. AgUmè¶m e§Hy$Mo dH«$ n¥ð>’$i H$mT>m.
2. e§Hy$Mr {ÌÁ¶m 7 g|.‘r. Am{U dH«$ n¥ð>^mJmMo joÌ’$i 176 Mm¡.g|.‘r. Agob Va ˶mMr {VaH$g C§Mr
H$mT>m.
3. Oa e§Hy$Mr {VaH$g C§Mr 8 g|.‘r. Am{U ˶mMo dH«$ n¥ð>’$i 60 Mm¡.g|.‘r. Agob Va VimMr {ÌÁ¶m
H$mT>m.
4. e§Hy$Mo dH«$ n¥ð>’$i 308 g|.‘r. Am{U {VaH$g C§Mr 14 g|.‘r. Amho. Va VimMr {ÌÁ¶m Am{U e§Hy$Mo g§nyU©
n¥ð>’$i H$mT>m.
5. b§~ dVw©imH$ma e§Hy$À¶m AmH$mamÀ¶m {dXþfH$mÀ¶m Q>monrÀ¶m VimMr {ÌÁ¶m 7 g|.‘r. Am{U C§Mr 24 g|.‘r.
Amho. Va Aem 10 Q>mo߶m ~Z{dʶmgmR>r bmJUmè¶m nmZmMo (sheet) joÌ’$i H$mT>m.
6. Oa XmoZ e§Hy$À¶m VimMm ì¶mg g‘mZ Am{U {VaH$g C§MrMo JwUmoÎma 4…3 Amho Va ˶m§À¶m joÌ’$im§Mo
JwUmoÎma H$mT>m.
7. (i) {ÌÁ¶m 5 g|.‘r.Am{U C§Mr 7 g|.‘r.Amho. Va b§~ dVw©imH$ma e§Hy$Mo KZ’$i H$mT>m.
8. XmoZ e§Hy$À¶m C§MrMo JwUmoÎma 1…3 Am{U ˶m§À¶m JwUmoÎma 3…1 Amho. Va ˶m§À¶m KZ’$im§Mo JwUmoÎma H$mT>m.
9. H$mQ>H$moZ {ÌH$moUm‘ܶo H$mQ>H$moZ H$aUmè¶m ~mOy§Mr bm§~r 6.3 g|.‘r. Am{U 10 g|.‘r. Amho. ˶mMr ‘moR>r
~mOy {’$adyZ e§Hy$ ~Z{dbm. Aem àH$mao ~Z{dboë¶m KZmMo KZ’$i H$mT>m.
10. b§~ dVw©imH$ma d¥Îm{MÎmr AmH$mamÀ¶m V§~yMr C§Mr 3 ‘r. n¶ªV Amho Am{U Z§Va O{‘Zrda OmñVrV OmñV
13.5 ‘r. C§MrMm b§~ dVw©imH$ma e§Hy$ ~ZVmo. Oa ˶mÀ¶m VimMr {ÌÁ¶m 14 ‘r. Amho Va ê$.2 Xa Mm¡.
‘r. à‘mUo ˶m V§~yÀ¶m AmVrb ^mJmZm a§J bmdʶmgmR>r ¶oUmam IM© H$mT>m.
darb Q>moH$ H$mnbobm (’«$ñQ>‘) e§Hy$ (Frustum of a cone)
Amnë¶m X¡Z§{XZ OrdZmV dmnaboë¶m nXmWmªÀ¶m
AmH$mamMm {dMma H$am.
Vo d¥Îm{MÎmr qH$dm e§Hy$ ¶mn¡H$s H$moUVohr Zmhr.
¶m AmH$mam§Zm H$m¶ åhUVmV? Vo H$go {‘i{dVmV?
Tumbler Bucket Cap S>ã~m ~mXbr Q>monr
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‘m{hV Amho !’«$ñQ>‘ hm b°Q>rZ eãX Amho. ˶mMm AW© ""H$mnbobm^mJ'' Am{U ˶mMo ~hþdMZ ’«$ñQ>m ho Amho.
MMm© H$am …’«$ñQ>‘ e§Hy$Mr VwbZm e§Hy$ Am{U d¥Îm{MÎmrerH$am. ˶m‘ܶo AgUmam gmaIonUm Am{U ’$aH$H$moUVo?
¶m àým§Mo CÎma XoʶmgmR>r Imbrb H¥$VrMm {dMma H$am.
H¥$Vr … ‘mVr qH$dm bd{MH$ nXmW© KodyZ b§~ dVw©imH$ma e§Hy$ V¶ma H$am. MmHy$Zo Vimbm g‘m§Va ^mJ H$mnm.
Vwåhmbm AmH¥$VrV XmI{dë¶mà‘mUo XmoZ KZnXmW© {‘iVmV.
Oa AmnU darb e§Hy$Mm ^mJ H$mTy>Z Q>mH$bm VaVimer KZnXmW© {e„H$ amhVmo. ˶mMm Vi Agboë¶me§Hy$À¶m ^mJmbm e§Hy$Mm ’«$ñQ>‘ (frustum) åhUVmV.
’«$ñQ>‘ e§Hy$bm XmoZ dVw©imH$ma Vi AgVmV. EH$ VimerAm{U Xþgam ˶mda AgyZ ˶m§Mr {ÌÁ¶m { Þ AgVo.
darb H¥$Vrdê$Z AmnU Agm {ZîH$f© H$mTy> H$s,Oa gnmQ> b§~ dVw©imH$ma e§Hy$Mm Vimer g‘m§Va ^mJ H$mnbm Am{U darb bhmZ e§Hy$ H$mTy>Z Q>mH$bm Va
{e„H$ am{hbobm Vi Agboë¶m e§Hy$À¶m ^mJmbm e§Hy$Mm ’«$ñQ>‘ (Frustum of the cone) Ago åhUVmV.AmVm Vwåhr S>ã~m, ~mXbr Am{U Q>monr À¶m AmH$mamZm
Zm§do Xody eH$Vm.Vwåhr ˶mZm Ago H$m åhUVm? JQ> H$ê$Z MMm© H$am.
‘wi e§Hy$ Am{U bhmZ H$mnbobm e§Hy$ ¶m§À¶m ‘mnm‘ܶo H$moUVog§~§Y AmhoV H$m? Imbr {Xboë¶m AmH¥$˶m§Mo {ZarjU H$am.
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g‘Om ‘yi e§Hy$À¶m VimMr {ÌÁ¶m, C§Mr Am{U {VaH$g C§Mr R, H Am{U L d bhmZ e§Hy$Mr, r, h Am{Ul Zo Xe©{dbobr Amho.
{ÌH$moU ABO Am{U AED Mo {ZarjU H$am Vo g‘ê$n AmhoV.åhUyZ ˶m§À¶m g§JV ~mOy à‘mUmV AmhoV.
i.e.EDBO
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Mensuration 385
Amåhr Agm {ZîH$f© H$mTy> H$s,
Oa e§Hy$À¶m darb Q>moH$mnmgyZ Vimbm g‘m§Va bhmZ e§Hy$ H$mnbm Va XmoZ e§Hy$Mr{VaH$g C§Mr, VimMr {ÌÁ¶m (‘wi e§Hy$ d {‘i{dbobm bhmZ e§Hy$) nañnam§Zm à‘mUmVAgVmV.
e§Hy$À¶m ’«$ñQ>‘Mr {VaH$g C§Mr hr ˶mÀ¶m C§Mr Am{U {ÌÁ¶oer H$er g§~§{YV Amho?'l ' hr ’«$ñQ>‘Mr {VaH$g C§Mr, 'h' hr C§Mr, 'R' hr Imbrb VimMr {ÌÁ¶m 'r' hr darb
VimMr {ÌÁ¶m Amho Ago ‘mZy.
g§~§Y l2 = h2 + (R – r)2 qH$dm l = 2 2h (R r) Ago {Xbo OmVo.
e§Hy$À¶m ’«$ñQ>‘Mo n¥ð>’$i Am{U KZ’$i (Surface area and volume of frustum of a cone)
Amåhmbm ‘m{hV Amho H$s, ’«$ñQ>‘ e§Hy$ hm e§Hy$ ABC Mm nm¶mbm g‘m§Va A'B'C hm bhmZ e§Hy$H$mnë¶mZ§Va {‘iVmo.
’«$ñQ>‘Mo = ABC ¶m e§Hy$Mo – A'B'C ¶m e§Hy$ModH«$ n¥ð>’$i nmíd© n¥ð>’$i nmíd© n¥ð>’$i
’«$ñQ>‘Mo g§nyU© n¥ð>’$i = ’«$ñQ>‘Mo LSA + XmoZ dVw©imH$ma VimMo joÌ’$i
’«$ñQ>‘Mo KZ’$i = ABC ¶m ‘yi e§Hy$Mo KZ’$i – A'B'C ¶m bhmZ e§Hy$Mo KZ’$i
Ooìhm ’$º$ ’«$ñQ>‘À¶m XmoZ Vim§Mr {ÌÁ¶m Am{U C§Mr {Xbobr Agob Va Voìhm ’«$ñQ>‘Mo joÌ’$i Am{UKZ’$i H$go H$mT>bo OmVo?
Oa h C§Mr l {VaH$g C§Mr r1Am{U r2 hr XmoZ ’«$ñQ>Z e§Hy$À¶m VimMr {ÌÁ¶m (r1> r2)Amho Ago ‘mZy.
Imbr {Xbobr gyÌo dmnê$Z à˶jnUo e§Hy$À¶m ’«$ñQ>‘Mo joÌ’$i Am{U KZ’$iH$mT>bo OmD$ eH$Vo.
* e§Hy$À¶m ’«$ñQ>‘Mo nmíd© n¥ð>’$i
= (r1+r2)l OoWo l = 2 21 2h +(r r )
* e§Hy$À¶m ’«$ñQ>‘Mo g§nyU© n¥ð>’$i
= (r1+r2)l + r12+ r2
2 = {(r1+r2)l + r12+r2
2} OoWo l = 2 21 2h +(r r )
* e§Hy$À¶m ’«$ñQ>‘Mo KZ’$i =13
h (r12+r2
2+r1r2)
[ Q>rn … {ÌH$moUmMr g‘ê$nVm dmnê$Z darb gyÌo H$mT>br OmD$ eH$VmV. na§Vw ¶oWo AmnU ˶m§Mo gyÌ V¶ma H$aVZmhr. AmnU gyÌo dmnê$Z CXmhaUo gmoS>{dVmo.
ñnîQ>rH$aUmË‘H$ CXmhaUo
CXmhaU 1 … e§Hy$À¶m ’«$ñQ>‘Mr {VaH$g C§Mr 4 g|.‘r. Am{U ˶mÀ¶m dVw©imH$ma VimMr n[a{‘Vr AZwH«$‘o 18g|.‘r. d 6 g|.‘r. Amho. Va ’«$ñQ>‘Mo dH«$ n¥ð>’$i Am{U g§nyU© n¥ð>’$i H$mT>m.
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CH$b … {Xbobo 2 r1 = 18 g|.‘r., 2 r2 = 6 g|.‘r., l = 4 g|.‘r.
r1 =9
g|.‘r. r2 =3
g|.‘r.
’«$ñQ>‘Mo dH«$ n¥ð>’$i = (r1+r2)l
=9 3
4=12 4
’«$ñQ>‘Mo CSA = 48 Mm¡.g|.‘r.’«$ñQ>‘Mo g§nyU© n¥ð>’$i = (r1+r2)l + r1
2+ r22
= 48 9 9 3 348 +
81 +
9
= 48 +81 7 9 7
22 22 = 48 + 25.8 + 2.9
’«$ñQ>‘Mo TSA = 76.7 Mm¡.g|.‘r.
CXmhaU 2 … ’«$ñQ>‘À¶m AmH$mamVrb H$Mam noQ>rÀ¶m XmoZ dVw©imH$ma Q>moH$m§Mr {ÌÁ¶m 15 g|.‘r. Am{U 8 g|.‘r.Amho. Oa ˶mMr Imobr 6.3 g|.‘r. Amho. Va H$Mam noQ>rMo KZ’$i H$mT>m.
CH$b … {Xbobo r1=15 g|.‘r., r2 = 8 g|.‘r., h = 63 g|.‘r.
H$Mam noQ>rMo KZ’$i (’«$ñQ>‘) =13
h (r12+r2
2+r1r2)
=1 22 633 7
(152+82+15×8)
=1
13
2271
639
3
(225+64+120)
= 66 × 409 = 26,994H$Mam noQ>rMo KZ’$i = 26,994 K.g|.‘r.
CXmhaU 3 … e§Hy$À¶m VimMr {ÌÁ¶m 12 g|.‘r. Am{U 20 g|.‘r. C§Mr Agboë¶me§Hy$À¶m darb Q>moH$mnmgyZ 3 g|.‘r. VimMr {ÌÁ¶m Agbobm e§Hy$ H$mnbm. Va{eamoq~XþnmgyZ Vmo {H$Vr A§Vamda H$mnbm nm{hOo? Aem [aVrZo {‘i{dboë¶m ’«$ñQ>‘MoKZ’$i H$mT>m.
CH$b … {Xbobo r1 = 12 g|.‘r., h1= 20 g|.‘r., r2 = 3 g|.‘r. h2 =?
Amåhmbm ‘m{hV Amho H$s, 1 1
2 2
r hr h 2
12 203 h h2 =
3 20 5 cm12 g|.‘r
{eamoq~XþnmgyZ 5 g|.‘r. A§Vamdê$Z Vmo H$mnbm nm{hOo.
’«$ñQ>‘Mo KZ’$i =13
h (r12+r2
2+r1r2)
63cm
8 cm
15 cm
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Mensuration 387
=1 22 153 7
(122+32+12×3) =110
7× (144+9+36)
=110
7× 189 = 2,970 K.g|.‘r.
’«$ñQ>‘Mo KZ’$i = 2,970 K.g|.‘r
CXmhaU 4 … e§Hy$À¶m AmH$mamÀ¶m JwimÀ¶m T>onrMm VimMm ì¶mg 10 g|.‘r. Am{U C§Mr10 g|.‘r. Amho. {eamoq~XÿnmgyZ 4 g|.‘r. Vimbm g‘m§Va bhmZ e§Hy$ H$mnbm. AemàH$mao {‘i{dboë¶m ’«$ñQ>‘Mo jooÌ’$i Am{U KZ’$i H$mT>m.
CH$b …ABO ¶m e§Hy$Mm ì¶mg = 10 g|.‘r. {ÌÁ¶m r1 =102 = 5 g|.‘r.
ABO ¶m e§Hy$Mr C§Mr = h1 = 10 g|.‘r.
AI BI O ¶m e§Hy$Mr C§Mr = h2 = 4 g|.‘r.
àW‘ BVa hdr Agbobr ‘m{hVr H$mTy>.
AI BI O e§Hy$Mr {ÌÁ¶m = r2
l1 Am{U l2 ¶m AZwH«$‘o ABO Am{U AI BI O ¶m e§Hy$Mr {VaH$g C§Mr Amho.
1 1
2 2
r hr h 2
5 10r 4 r2 =
5 410
= 2 g|.‘r.
l12 = h1
2+ r12 = 102+ 52 = 100 + 25 = 125 l1 = 125 5 5 cm g|.‘r.
l22 = h2
2+ r22 = 42 + 22 = 16 + 4 = 20 l2 = 20 2 5 cmg|.‘r.
(i) ABO ¶m e§Hy$Mo nmíd© n¥ð>’$i = r1l1 = 5 5 5 25 5
ABO ¶m e§Hy$Mo LSA = 25 5 Mm¡. g| ‘r.
e§Hy$ AI BI O nmíd© (dH«$) n¥ð>’$i = r2l2 = 2 2 5 4 5
AI BI O ¶m e§Hy$Mo LSA = 4 5 Mm¡.g|.‘r.
’«$ñQ>‘ e§Hy$Mo nmíd© n¥ð>’$i = ABO e§Hy$Mo LSA - AI BI O e§Hy$Mo LSA
= 25 5 4 5 21 53 21 225
7 1 = 66 5 Mm¡.g| ‘r.
’«$ñQ>‘ e§Hy$Mo nmíd© n¥ð>’$i = 66 5 Mm¡.g|.‘r. qH$dm. 147.84 Mm¡.g|.‘r.
(ii) ABO e§Hy$Mo g§nyU© joÌ’$i = r1 (r1+l1)
5 5 5
ABO e§Hy$Mo TSA = 25 5 Mm¡.g| ‘r.
AI BI O e§Hy$Mo g§nyU© joÌ’$i = r2 (r2+l2)
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2 5 5
AI BI O e§Hy$Mo TSA = 4 5 Mm¡.g| ‘r.
’«$ñQ>‘Mo g§nyU© joÌ’$i = ABO e§Hy$Mo TSA - AI BI O e§Hy$Mo TSA
5 - 4 5
5 - 4) = 21 53 21 221 5
7 1
’«$ñQ>‘Mo g§nyU© joÌ’$i= 66 5 Mm¡.g|.‘r. qH$dm 213.84 Mm¡.g|.‘r.
(iii) ABO e§Hy$Mo KZ’$i =13
r12 h1 =
13
5 5 10
ABO e§Hy$Mo KZ’$i2503
K.g|.‘r.
AI BI O e§Hy$Mo KZ’$i =13
r22 h2=
13
2 2 4
AI BI O e§Hy$Mo KZ’$i =163
K.g|.‘r.
’«$ñQ>‘ e§Hy$Mo KZ’$i = ABO e§Hy$Mo KZ’$i AI BI O e§Hy$Mo KZ’$i
=2503
–163
=2343
’«$ñQ>‘ e§Hy$Mo KZ’$i = 78 K.g|.‘r. qH$dm 245.14 K.g|.‘r.
AmnU à˶jnUo dmnê$Z gwÕm e§Hy$À¶m ’«$ñQ>‘Mo nmíd© n¥ð>’$i, g§nyU© n¥ð>’$i Am{U KZ’$i H$mTy> eH$Vmo.
ñdmܶm¶ 15.3
1. (âbm°da nm°Q>) ’y$bXmUr hr ’«$ñQ>‘ e§Hy$À¶m ñdê$nmV Amho. Q>moH$m§Mr n[a{‘Vr 44 g|.‘r. Am{U 8.4g|.‘r. Amho. Oa {VMr Imobr 14 g|.‘r. Amho Va ˶m‘ܶo {H$Vr nmUr ‘mdVo?
2. ~mXbr hr ’«$ñQ>‘ ñdê$nmVrb AgyZ {VÀ¶m darb Am{U Imbrb dVw©im§Mr {ÌÁ¶m 15 g|.‘r. Am{U 10g|.‘r. AmhoV. {VMr Imobr 12 g|.‘r. Amho. Va {VMo dH«$ n¥ð>’$i Am{U g§nyU© n¥ð>’$i H$mT>m. (CÎma À¶mñdê$nmV 춺$ H$am)
3. e§Hy$À¶m VimMr {ÌÁ¶m 24 g|.‘r. Am{U C§Mr 45 g|.‘r. d {VaH$g C§Mr 45 g|.‘r. Agboë¶m e§Hy$À¶mdarb Q>moH$mnmgyZ 17 g|.‘r. C§Mrda H$mnbr. {e„H$ am{hboë¶m ’«$ñQ>‘ e§Hy$Mo KZ’$i H$mT>m. (CÎma À¶mñdê$nmV 춺$ H$am)
4. ^m§S>o ’«$ñQ>‘ e§Hy$À¶m AmH$mamMo Amho. ˶mMr EH$m Q>moH$mdarb {ÌÁ¶m 8 g|.‘r.Am{U C§Mr 14 g|.‘r. Amho. ˶mMo KZ’$i
56763
K.g|.‘r. Amho. Va˶mÀ¶m Xþgè¶m Q>moH$mMr {ÌÁ¶m H$mT>m.
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Mensuration 389
Jmob (Sphere)
‘mJrb ^mJmV Ho$boë¶m H¥$Vrà‘mUoM H¥$Vr H$am.
EH$ dVw©imH$ma MH$Vr ¿¶m Am{U ˶mÀ¶m ì¶mgmda Xmoar {MH$Q>dm. Vr{’$adm Am{U ZdrZ V¶ma hmoUmè¶m KZmH¥$VrMo {ZarjU H$am.
Vo H$emgmaIo {XgVmV? ˶mbm Jmob Ago åhUVmV.
Oa dVw©imH$ma MH$Vr ˶mÀ¶m ì¶mgm^modVr {’$a{dbr Va V¶ma hmoUmè¶mKZmH¥$Vrbm Jmob Ago åhUVmV.
dVw©imMm ‘ܶ Ooìhm Vmo {’$a{dbm AgVm Jmob ~ZVmo Voìhm Vmo JmobmMm ‘ܶ~ZVmo. V¶ma Pmboë¶m Jmobm‘ܶo ‘ܶ q~Xÿ ˶mÀ¶m AdH$memVrb gd© q~Xÿ nmgyZ g‘mZA§Vamda AgVmV.
åhUyZ Jmob hr {Ì‘rVr d AmH¥$Vr qH$dm KZmH¥$Vr AgVo. Or AdH$memVrb gd©q~XÿZr ~Zbobr AgVo Oo pñWa A§Vamda AgVmV ˶m§Zm {ÌÁ¶m åhUVmV Am{U pñWaq~Xÿbm JmobmMm ‘ܶ Ago åhUVmV.
^ard Jmob hm eãX KZmH¥$VrgmR>r dmnaVmV {OMm n¥ð>^mJ Jmob AgVmo {Vbm joÌ’$i Am{U KZ’$i XmoÝhrAgVmV.
Amnë¶m g^modVmbr JmobmÀ¶m AmH$mamÀ¶m AZoH$ dñVy AmhoV.
Imbr {Xboë¶m CXmhaUm§Mm {dMma H$am.
JmobmÀ¶m AmH$mamÀ¶m nXmWm©‘ܶo Vwåhr {H$Vr n¥ð>^mJ nmhmb?
VoWo ’$º$ EH$M AgVmo Omo dH«$mH$ma AgVmo.
AmVm M|Sy> gmaIm Jmob Amho Ago g‘Om ˶mÀ¶m ‘Ymo‘Y ~amo~a ‘ܶmVyZ OmUmao gnmQ> VwH$S>o H$am.
JmobmMo XmoZ g‘mZ ^mJ hmoVmV. JmobmÀ¶m à˶oH$ ^mJmbm
AY©Jmob Ago åhUVmV.
Jmob Am{U AY©JmobmÀ¶m n¥ð>^mJmMo joÌ’$i (Surface area ofsphere and hemisphere)
‘Ooera H¥$VrÀ¶m ghmæ¶mZo JmobmÀ¶m n¥ð>^mJmMo joÌ’$iH$mT>ʶmMo gyÌ {‘i{dbo OmVo. Vwåhmbm ^moJè¶mÀ¶m g^modVmbr Xmoar Jw§S>miyZ IoiʶmÀ¶m Ioim{df¶r ‘m{hVrAmho. Imbrb H¥$Vr Á¶m‘ܶo JmobmH$ma dñVw modVr Xmoam Jw§S>miyZ JmobmMo n¥ð>’$i H$mT>ʶmMo gyÌ aMʶmg ‘XVH$aVo. H¥$VrMm Aä¶mg H$am Am{U JQ> H$ê$Z H$aʶmMm à¶ËZ H$am.
• ßb°ñQ>rH$Mm M|Sy> ¿¶m.
• M|Sy>À¶m darb Q>moH$mda Q>mMUr Q>moMm.
• M|Sy>da g‘mZ[a˶m g§nyU© n¥ð>^mJmda Xmoam Jw§S>mië¶mZo dH«$ n¥ð>’$i ¶oVo. Xmoam pñWa R>odʶmgmR>r ˶mdaQ>mMUr Q>moMm.
M|Sy> JmoQ>r
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• Xmoè¶mÀ¶m gwadmVrÀ¶m Am{U eodQ>À¶m q~Xÿda IwU H$am.
• gmdH$menUo JmobmÀ¶m n¥ð>^mJmda Jw§S>mibobm Xmoam gmoS>m Am{U ˶mMr bm§~r ‘moOm.
• Xmoè¶mMo g‘mZ Mma ^mJ H$am.
• M|Sy>Mm ì¶mg Am{U {ÌÁ¶m ‘moOm.
• EH$ H$mJXmMo nmZ ¿¶m Am{U M|Sy>À¶m {ÌÁ¶oMr g‘mZ {ÌÁ¶oMr Mma dVw©io H$mT>m.
• AmH¥$VrV XmI{dë¶mà‘mUo EH$m VwH$S>çmZo à˶oH$ dVw©i ^am.
¶m H¥$Vrdê$Z Vwåhr H$m¶ nmhmb Am{U H$moUVm AZw‘mZ H$mT>mb?
Xmoè¶mZo JmobmMo (M|Sy>Mr) nyU© joÌ’$i ì¶mnbobo hmoVo ˶mZo nyU©nUo Mma dVw©im§Mo joÌ ^aVo. ˶m gdmªMr{ÌÁ¶m Jmobmer g‘mZ Amho.
ho gwM{dVo H$s JmobmMo dH«$ n¥ð>’$i ho dVw©imÀ¶m n¥ð>’$imÀ¶m Mma nQ> Amho. OoWo XmoÝhr Jmob Am{U dVw©i¶m§Mr {ÌÁ¶m g‘mZ Amho.
JmobmMo dH«$ n¥ð>’$i = 4 × dVw©imMo joÌ’$i = 4 × r2 = 4 r2
JmobmMo dH«$ n¥ð>’$i = 4 r2 Mm¡.EH$H$ qH$dm JmobmMo n¥ð>’$i 4 r2 Mm¡.EH$H$
¶mH$S> o bj XoUo ‘Oo{ea Amho H$s, Jm obmMo n ¥ð>’$i ho ˶m‘ܶo Agboë¶m d¥Îm{MÎmrÀ¶m dH«$n ¥ð >’$imBVHo $ AgVo.
AmH¥$VrMo {ZarjU H$am.'r' {ÌÁ¶oÀ¶m Jmob d¥Îm{MÎmrÀ¶m AmV R>odbobm Amho. ˶mMr {ÌÁ¶m gwÕm 'r'
Am{U C§Mr '2r' Amho.JmobmMo n¥ð>’$i = 4 r2
d¥Îm{MÎmrMo dH«$ n¥ð>’$i = 2 rh = 2 r × 2r = 4 r2
JmobmMo n¥ð>’$i = d¥Îm{MÎmrMo nmíd© n¥ð>’$iOoWo Jmob Am{U d¥Îm{MÎmrÀ¶m {ÌÁ¶m g‘mZ AmhoV Am{U d¥Îm{MÎmrMr C§Mr hm JmobmÀ¶m ì¶mgmer g‘mZ
Amho.AmVm, AmnU AY©JmobmMo dH«$ n¥ð>’$i H$mTy>. {ZarjU H$am H$s Amnë¶mOdi ^ard AY©Jmob Am{U
nmoH$i AY©Jmob AmhoV.Amnë¶mbm ‘m{hV Amho H$s AY©Jmob hm AJXr ~amo~a AYm© Jmob Amho. hr ¶wº$s dmnê$Z ^ard Am{U
nmoH$i AY©JmobmMo n¥ð>’$i H$mTy>.
(i) ^ard AY©JmobmMo dH«$ n¥ð>’$i (Curved surface area of solid hemisphere)
^ard AY©JmobmMo dH«$ n¥ð>’$i (C.S.A) = ard JmobmMo (C.S.A)=
24 r2
= 2 r2
2
^ard AY©JmobmMo dH«$ n¥ð>’$i = 2 r2 Mm¡.EH$H$
(ii) nmoH$i AY©JmobmMo g§nyU© n¥ð>’$i (Total surface area of solidhemisphere)
^ard AY©Jmob
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Mensuration 391
^ard AY©JmobmMo n¥ð>’$i (TSA) = AY©JmobmMo n¥ð>’$i (CSA) + dVw©imH$ma VimMo joÌ’$i= 2 r2 + r2 = 3 r2
^ard AY©JmobmMo g§nyU© n¥ð>’$i (T.S.A) = 3 r2 Mm¡. EH$H$
(Vwåhr nm{hbo Agob H$s, dmT>{XdgmÀ¶mdoir {H«$g‘g PmS>mda JmobmH$ma gOmdQ>rÀ¶m dmnaboë¶m dñVy B.
hm Jmob AZoH$ e§Hy$nmgyZ ~Zbobm Amho.
JmobmMr H$ënZm H$am, Or AZoH$ bhmZ e§Hy$ dmnê$Z ~Z{dbobm Amho, Á¶mMr {ÌÁ¶m 'R' Am{U C§Mr 'h' Amho.Agm {dMma H$ê$ eH$Vm H$s, Jmob bhmZ-bhmZ e§Hy$nmgyZ ~Zbobm Amho. Á¶m§Mr C§Mr 'h' hr JmobmMr {ÌÁ¶m'r' er g‘mZ Am{U dVw©imH$ma nm¶m AgVmo.
à˶oH$ e§Hy$Mo KZ’$i =13
× VimMo joÌ’$i × C§Mr.
n{hë¶m e§Hy$Mo KZ’$i =13
× B1 × r, Xþgè¶m e§Hy$Mo KZ’$i =13
× B2 × r
{Vgè¶m e§Hy$Mo KZ’$i =13
× B3 × r, n ì¶m e§Hy$Mo KZ’$i =13
× Bn × r
JmobmMo KZ’$i = gd© e§Hy$À¶m KZ’$im§Mr ~oarO
=13
B1r +13
B2r +13
B3r+........+13
Bnr =13
r(B1 + B2 + B3 + .......Bn)
Amåhr nmhVmo H$s, Jmob ~Z{dUmè¶m gd© e§Hy$À¶m Vim§À¶m joÌ’$im§Mr ~oarO hr JmobmÀ¶m n¥ð>’$imerg‘mZ AgVo. Á¶mAeu JmobmMo n¥ð>’$i 4 r2 Amho.
Amåhmbm {‘iob,
JmobmMo KZ’$i =13
r(4 r2) = 34r
3
JmobmMo KZ’$i = 34 r3
KZ EH$H$
{ÌÁ¶m (r) hr g‘mZ Agboë¶m Jmob Am{U e§Hy$À¶m KZ’$imÀ¶m g§~§Ym{df¶r A˶§V Hw$VwhbmMr Jmoï>Amho.
g§~§YmMm Aä¶mg H$am.
JmobmMo KZ’$i ho e§Hy$À¶m KZ’$imÀ¶m Mma nQ> Amho.
JmobmMo KZ’$i = 4 × e§Hy$Mo KZ’$i
= 4 ×13
r2h = 4 ×13
r2 × r = 4 ×13
r2 =43
r3
JmobmMo KZ’$i =43
r3
^ard AY©JmobmMo KZ’$i (Volume of a solid hemisphere)
^ard AY©JmobmMo KZ’$i =12 × ^ard JmobmMo KZ’$i = 3 31 4 2r r
2 3 3
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392 UNIT-15
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaUo 1 … 21 g|.‘r. {ÌÁ¶oÀ¶m JmobmMo n¥ð>’$i H$mT>m. r = 21 g|.‘r.
CH$b … JmobmMo n¥ð>’$i = 4 r2 =22
47
213
21cmMm¡.g|.‘r.
JmobmMo n¥ð>’$i = 5544 Mm¡.g|.‘r.
CXmhaU 2 … 14 g|.‘r. {ÌÁ¶oÀ¶m AY©JmobmMo dH©$ n¥ð>’$i (CSA) Am{U g§nyU© n¥ð>’$i (TSA) H$mT>m.
CH$b … AY©JmobmMo dH«$ n¥ð>’$i (CSA) = 2 r2 =22
27
142
14cmMm¡.g|.‘r.
AY©JmobmMo dH«$ n¥ð>’$i (CSA) = 1232 Mm¡.g|.‘r.
AY©JmobmMo g§nyU© n¥ð>’$i (TSA) = 3 r2 =22
37
142
14cmMm¡.g|.‘r.
AY©JmobmMo g§nyU© n¥ð>’$i (TSA) = 1848 Mm¡.g|.‘r.
CXmhaU 3 … 3 g|.‘r. {ÌÁ¶oÀ¶m JmobmMo KZ’$i H$mT>m.
CH$b … r = 3 g|.‘r. JmobmMo KZ’$i = 34r
3 =
43
22 37
3 3cmK.g|.‘r. = 113.14 K.g|.‘r.
CXmhaU 4 … AY© JmobmH$ma dmQ>rMm AmVrb ì¶mg 9 g|.‘r.Amho Va bm ‘ܶo gm‘mdUmè¶m XþYmMo KZ’$iH$mT>m.
CH$b … d = 9 g|.‘r. r =92 g|.‘r.
AY©JmobmMo KZ’$i = 32r
3=
23
22 97
3
29 92 2
K.g|.‘r.=5346 190.92cm28
K.g|.‘r.
AY©JmobmH$ma dmQ>rMo KZ’$i = 190.92 [1 K.g|.‘r.=1 {‘.br. ]˶m‘ܶo gm‘mdboë¶m XþYmMo KZ’$i = 190.92 {‘.br. [1 K.g|.‘r.=1 {‘.br. ]
CXmhaU 5 … AY©JmobmH$ma dmQ>rMr AmVrb {ÌÁ¶m 18 g|.‘r. AgyZ Vr ’$imÀ¶m agmZo ^abobr Amho. hm ag 3g|.‘r. {ÌÁ¶m Am{U 9 g|.‘r. C§Mr Agboë¶m d¥Îm{MÎmr AmH$mamÀ¶m ~mQ>br‘ܶo hm ag ^abm Va dmQ>r nyU©nUoImbr H$aʶmgmR>r {H$Vr ~mQ>ë¶m ^amì¶m bmJVrb?
CH$b … AY©Jmob … r = 18 g|.‘r. V = ? AY©JmobmMo KZ’$i = 32 r3
AY©JmobmH$ma dmQ>rMo KZ’$i =2 22
18 18 18cm3 7
g|.‘r.
d¥Îm{MÎmr … r = 3, h = 9
d¥Îm{MÎmrMo KZ’$i = r2h EH$m ~mQ>brMo KZ’$i =22 3 3 9cm7
K.g|.‘r.
~mQ>btMr g§»¶m = AY©JmobmH$ma dmQ>r‘Yrb ’$imÀ¶m agmMo KZ’$i
EH$m d¥Îm{MÎmr AmH$mamÀ¶m ~mQ>brVrb ’$imÀ¶m agmMo KZ’$i
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Mensuration 393
=
23
227
186
2
186
182
227
3 3 9 = 48
Amdí¶H$ Agboë¶m ~mQ>ë¶m§Mr g§»¶m = 48
CXmhaU 6 … YmVyÀ¶m Jmoù¶mMm ì¶mg 4.2 g|.‘r. Amho. ˶mbm {dVidyZ 8.4 g|.‘r. C§MrMm b§~ dVw©imH$ma
e§Hy$ ~Z{dbm Va e§Hy$À¶m VimMm ì¶mg H$mT>m..
CH$b … d = 4.2 g|.‘r. r =4.22 = 2.1 g|.‘r. e§Hy$ : h = 8.4 g|.‘r.
JmobmMo KZ’$i = e§Hy$Mo KZ’$i
3s
4r
3= 2
c c1
r h3
2Cr =
43
3Sr
13 Ch =
4 2.1 2.1 2.18.4 2.1
= 2.1 × 2.1 rC = 2.1 2.1 = 2.1 cm
e§Hy$À¶m VimMr {ÌÁ¶m = 2.1 g|.‘r.
CXmhaU 7 … nmoH$i AY©JmoimH$mam AmH$mamÀ¶m e§ImMm AmVrb Am{U ~mhoarb ì¶mg AZwH«$‘o 6 g|.‘r. Am{U10 g|.‘r. AmhoV. Vr {dVidyZ 14 g|.‘r. ì¶mgmMm ^ard e§Hy$ ~Z{dʶmV Ambm. Aem[aVrZo ~Z{dboë¶me§Hy$Mr C§Mr H$mT>m.
CH$b … nmoH$i AY©Jmob … ~mhoarb {ÌÁ¶m R =102 = 5g|.‘r. AmVrb {ÌÁ¶m r =
62 = 3 g|.‘r.
e§Hy$ … r =142 = 7 g|.‘r. h = ?
nmoH$i AY©JmobmMo KZ’$i = e§Hy$Mo KZ’$i3 32
(R r )3
= 21r h
3
h=
2 23
3 3(R r )
13
3 3
22
2(R r )r
r=
3 3
2
2(5 3 ) 2(125 27)497
=98
22
49 = 4 g|.‘r.
V¶ma Pmboë¶m e§Hy$Mr C§Mr = 4 g|.‘r.
CXmhaU 8 … XmoZ ^ard YmVyÀ¶m Jmoù¶mMr {ÌÁ¶m r1 Am{U r2 Amho. Jmob {dVidyZ EH${ÌVnUo (r1 + r2) C§MrMm
^ard e§Hy$ ~Z{dbm. Va e§Hy$Mr {ÌÁ¶m 2 21 2 1 22 r r r r ho XmIdm.
CH$b … (Jmob 1 + Jmob 2) Mo KZ’$i = e§Hy$Mo KZ’$i
3 31 2
4 4r r
3 3=
2C 1 2
1r (r r )
3
3 31 2
4 r r3
= 2C 1 2
1 r (r r )3
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394 UNIT-15
rC=
43
3 31 2r r
13 1 2r r =
1 24 r r 2 21 1 2 2
1 2
r r r r
r r
2Cr = 2 2
1 1 2 24 r r r r
rC=2 2
1 1 2 24 r r r r = 2 21 1 2 22 r r r r
e§Hy$À¶m VimMr {ÌÁ¶m = 2 21 1 2 22 r r r r
CXmhaU 9 … 1 g|.‘r. {ÌÁ¶oMm ^ard Jmob {dVidyZ 100 g|.‘r. bm§~rMr Vma ~Z{dʶmV Ambr. VmaoMr{ÌÁ¶m H$mT>m.
CH$b … Jmob r = 1 g|.‘r.
Vma hr d¥Îm{MÎmr Amho.
d¥Îm{MÎmr h = 100 g|.‘r. r = ?
JmobmMo KZ’$i = Vma (d¥Îm{MÎmr)Mo KZ’$i
3S
4r
3 = 2
cy cyr h 2Cyr =
43
3sr
cyh=
3s
cy
4r3 4 =
4 31 1 1cm3 100 25cm =
175 K.g|.‘r.
rCy=1 175 5 3
g|.‘r.= 0.11 g|.‘r.
VmaoMr {ÌÁ¶m = 0.11 g|.‘r.
ñdmܶm¶ 15.4
1. JmobmMo n¥ð>’$i H$mT>m Oa ˶mMr {ÌÁ¶m (i) 14 g|.‘r.
2. 5 g|.‘r. {ÌÁ¶oÀ¶m AY©JmobmMo g§nyU© (TSA) n¥ð>’$i H$mT>m.
3. bmH$S>mÀ¶m AY©JmobmH$ma dmQ>rMm AmVrb ì¶mg 10.5 g|.‘r. Amho Va 100 Mm¡.g|.‘r. bm < $.12 à‘mUoAmVrb ^mJmbm a§J bmdʶmgmR>r ¶oUmam IM© H$mT>m.
4. 15 g|.‘r. ~mOyÀ¶m KZmnmgyZ H$mnboë¶m ‘moR>çmV ‘moR>çm JmobmMo joÌ’$i (dH«$ n¥ð>’$i) H$mT>m.
5. JmobmMo KZ’$i H$mT>m. Oa ˶mMr {ÌÁ¶m 7 g|.‘r.Amho.
6. JmobmMo dH«$ n¥ð>’$i 154 Mm¡.g|.‘r. Amho. Va ˶mMo KZ’$i H$mT>m.
7. ^ard AY©JmobmMo KZ’$i 1152 K.g|.‘r. Amho. Va ˶mMo dH«$ n¥ð>’$i H$mT>m.
8. Am¡fYmÀ¶m JmoirMm AmH$ma JmobmH$ma AgyZ ˶mMm ì¶mg 3.5 {‘.‘r. Amho. hr H°$mgwbMr Jmoir^aʶmgmR>r {H$Vr Am¡fY bmJob?
9. b§~ dVw©imH$ma YmVyÀ¶m e§Hy$Mr C§Mr 20 g|.‘r. Am{U VimMr {ÌÁ¶m 5 g|.‘r. Amho. Vmo {dVidyZ Jmob~Z{dbm Va JmobmMr {ÌÁ¶m H$mT>m
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Mensuration 395
10.EH$m YmVyÀ¶m Jmoù¶mMm ì¶mg 18 g|.‘r. Amho. ˶mbm {dVidyZ 0.4 g|.‘r. ì¶mgmMr Vma ~Z{dʶmV Ambr.
Va ˶m VmaoMr bm§~r H$mT>m.
KZ nXmWmªMm g§¶moJ (Combination of solids)
KZnXmW© Ogo H$s, KZ, KZm¶V, bmobH$, {na°{‘S>, d¥Îm{MÎmr, e§Hy$ Am{U Jmob {df¶r Vwåhmbm ‘m{hVr
Amho. Vwåhmbm ˶m§Mo joÌ’$i Am{U KZ’$i H$go H$mT>bo OmVo Vo ‘m{hV Amho. Ago KZ AmH$ma Amnë¶m
g^modVmbÀ¶m nXmWm©‘YyZ AmoiIUo gd© gmYmaU Amho.
AmVm Imbrb nXmW© Am{U ˶m§Mo AmH$ma ¶m§Mo {ZarjU H$am. JQ>m‘ܶo MMm© H$am Am{U à˶oH$mMm AmH$ma
AmoiIm
à˶oH$ KQ>ZoVrb nXmW© ho XmoZ qH$dm A{YH$ KZnXmWm©nmgyZ ~Zbobo AmhoV. åhUyZ ˶mn¡H$s à˶oH$ hmKZnXmWmªMm g§¶moJ Amho.
IoiUo V obmMr Q>mH$s
Cone + Hemisphere
harV J¥ham±Ho$Q>a
ewH«$+KZm¶VAY© d¥V{dVr +KZm¶V
Aem KZnXmWmªMo KZ’$i Am{U joÌ’$i H$go H$mT>bo OmVo? KZnXmWmªÀ¶m g§¶moJmMo joÌ’$i Am{U KZ’$iH$mT>ʶmMm Aä¶mg H$ê$.
Hemisphere + Cylinder+ Hemisphere AY©Jmob + d¥Îm{MÎmr
e§Hw$ + AY©Jmob
IoiUo VobmMm Q>±H$a Ap½Z~mU Z‘wZm harV J¥h PmonS>r
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396 UNIT-15
KZnXmWmªÀ¶m g§¶moJmMo joÌ’$i … (Surface area of combination of solids)
IoiʶmÀ¶m CXmhaUmMm {dMma H$am. Amåhmbm Ago {XgyZ ¶oVo H$s, IoiʶmMo joÌ’$i hoAY©JmobmMo dH«$n¥ð>’$i Am{U e§Hy$Mo n¥ð>’$i ¶m§Mr ~oarO Amho..
IoiʶmMo g§nyU© joÌ’$i (TSA) = AY©JmobmMo n¥ð>’$i (CSA)
IoiʶmMo dH«$ n¥ð>’$i (CSA) = AY©JmobmMo (CSA) + e§Hy$Mo CSA
AemM àH$mao BVa CXmhaUmVrb AmnU g§nyU© n¥ð>’$i Am{U dH«$ n¥ð>’$i Imbrbà‘mUo H$mTy> eH$Vmo
VobmÀ¶m Q>mH$sMo TSA = AY©JmobmMo CSA + d¥Îm{MÎmrMo CSA + AY©JmobmMo CSA
VobmÀ¶m Q>mH$sMo CSA = AY©JmobmMo CSA + d¥Îm{MÎmrMo CSA + AY©JmobmMo CSA
A{¾~mU à{VH¥$VrMo TSA = d¥Îm{MÎmrMo CSA + VimMo joÌ’$i + e§Hy$Mo CSA
A{¾~mU à{VH¥$VrMo CSA = d¥Îm{MÎmrMo CSA + e§Hy$Mo CSA
PmonS>rMo TSA = KZm¶VmMo CSA + VimMo joÌ’$i + d¥Îm{MÎmrMo AY} CSA
PmonS>rMo CSA = KZm¶VmMo CSA + d¥Îm{MÎmrMo AY} CSA
darb CXmhaUmdê$Z AmnU Agm {ZîH$f© H$mTy> H$s KZnXmWmªÀ¶m g§¶moJmMog§nyU© n¥ð>’$i ho EH${ÌV Ho$boë¶m gd© KZnXmWmªMr ~oarO AgVo qH$dm ZgVo.
AmnU Imbrb Zm|Xr bjmV R>ody.
• KZnXmWmªÀ¶m g§¶moJm§Mo joÌ’$i ho ’$º$ EH${ÌV Ho$boë¶m KZnXmWmªÀ¶m g§¶moJmMo
joÌ’$i ZgVo H$maU OmoS>V AgVmZm g§nyU© joÌ’$imMm H$mhr ^mJ Zmhrgm
hmoVmo.
• EH${ÌV Ho$boë¶m KZnXmWmªÀ¶m dH«$ n¥ð>’$im§Mr ~oarO gwÕm ZgVo H$maU dH«$
n¥ð>^mJ gmoSy>Z BVa ^mJ ˶m§À¶m g§nyU© joÌ’$imV {‘gibm OmVmo.
• KZnXmWmªÀ¶m g§¶moJmMo dH«$ n¥ð>’$i ho EH${ÌV Ho$boë¶m KZnXmWmªÀ¶m g§¶moJmÀ¶m dH«$ n¥ð>’$im§Mr ~oarO
Agy eH$Vo.
• KZnXmWmªÀ¶m g§¶moJmMo dH«$ n¥ð>’$i ho EH${ÌV Ho$boë¶m KZnXmWmªÀ¶m g§¶moJmÀ¶m dH«$ n¥ð>’$im§Mr ~oarO
Agy eH$V Zmhr. H$maU dH«$ n¥ð>^mJ gmoSy>Z BVa ^mJ gwÕm {‘i{dbo OmVmV.
AmVm KZ nXmWmªÀ¶m g§¶moJmÀ¶m dH«$ n¥ð>’$imda AmYmarV H$mhr CXmhaUo gmoS>dy¶m.
IoiUo
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Mensuration 397
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1 … d¥Îm{MÎmr AmH$mamÀ¶m ^m§S>çm§Mr {ÌÁ¶m 6 g|.‘r. Am{U C§Mr 15 g|.‘r. AgyZ Vo AmB©gH«$s‘Zo
^abobo Amho. darb Q>moH$ AY©dVw©imH$ma Agboë¶m e§Hy$Zo 10 {dÚm϶mª‘ܶo g‘mZ[a˶m g§nyU© AmB©gH«$s‘
dmQ>bm. e§Hy$Mr C§Mr VimÀ¶m {ÌÁ¶oÀ¶m 4 nQ> Amho. Va AmB©gH«$s‘À¶m e§Hy$Mr (H$moZmMr) {ÌÁ¶m H$mT>m.
4r r r
6 cm
15 c
m
CH$b … darb Q>moH$ AY©dVw©imH$ma AgUmè¶m e§Hy$Mo KZ’$i
= 2 31 2r h r3 3
= 2 31 2r 4r r3 3
= 3 34 2r r3 3
=6
2
33r = 2 r3
AY©JmobmH$ma darb Q>moH$mÀ¶m 10 e§Hy$Mo KZ’$i = 10 × 2 r3 = 20 r3
d¥Îm{MÎmr AmH$mamÀ¶m ^m§S>çmVrb AmB©gH«$s‘ KZ’$i = r2h × 6cm × 6cm × 15 cm = 540 cm3
AY©JmobmH$ma darb Q>moH$mÀ¶m 10 e§Hy$Mo KZ’$i= d¥Îm{MÎmr AmH$mamÀ¶m ^m§S>çmVrb AmB©gH«$s‘ Mo
KZ’$i
20 r3 = 540 r3 =54
270
2 0 = 27 r = 3 27 r = 3 g|.‘r.
CXmhaU 2 … b§~ dVw©imH$ma d¥Îm{MÎmrda e§Hy$À¶m AmH$mamMm KZnXmW© Amho. XmoÝhtÀ¶m VimMr {ÌÁ¶m g‘mZ
Amho. d¥Îm{MÎmrÀ¶m Vimda e§Hy$Mm Vi ~g{dbobm Amho. Oa e§Hy$À¶m VimMr {ÌÁ¶m Am{U C§Mr AZwH«$‘o 7
g|.‘r. Am{U 10 g|.‘r. Amho. Am{U EHy$U KZnXmWm©Mr C§Mr 30 g|.‘r. Amho Va KZnXmWm©Mo KZ’$i H$mT>m.
CH$b … d¥Îm{MÎmr ^mJ … r = 7 g|.‘r., h = 30 – 10 = 20 g|.‘r.
e§Hy$Mm ^mJ … r = 7 g|.‘r., h = 10 g|.‘r.
KZnXmWm©Mo KZ’$i = d¥Îm{MÎmrMo KZ’$i + e§Hy$Mo KZ’$i
= r2h + 21r h
3=
227
7 7 20cmK.g|.‘r. +1 223 7
7 7 10
= 3080 K.g|.‘r.+1540
3K.g|.‘r.
= 3080 + 513.33 K.g|.‘r.
KZnXmWm©Mo KZ’$i = 3593.33 K.g|.‘r.
CXmhaU 3 … EH$ IoiUo g‘mZ {ÌÁ¶oÀ¶m AY©Jmobmda e§Hy$ ñdê$nmV ~g{dbobo Amho. e§Hy$À¶m AmH$mamMmì¶mg 6 g|.‘r. Am{U C§Mr 4 g|.‘r. Amho. Va KZnXmWm©Mo dH«$ n¥ð>’$i Am{U KZ’$i H$mT>m.
g|.‘r.
g|.‘r.
g|.‘r.g|.‘r.
g|.‘r
.
g|.‘
r.A
B
D
30
10
20
E7
7
7
©
KTBS
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398 UNIT-15
126 m
21m
16m
30 m 30 mO5m
16 ‘
r.
30 ‘r. 30 ‘r.
‘r.
‘r.
‘r.
CH$b … e§Hy$Mm ^mJ JmobmH$ma mJr = 3 g|.‘r., h = 4 g|.‘r. r = 3 g|.‘r.
l2 = r2 + h2 = 32 + 42 = 9 + 16l2 = 25
l = 25 = 5 g|.‘r.
IoiʶmMo dH«$ n¥ð>’$i= AY©JmobmMo CSA + e§Hy$Mo CSA
= 2 r2 + rl = 2 222 222 3 3cm 3 5cm
7 7Mm¡.g|.‘r.
= 2 2396 330cm cm
7 7Mm¡.g|.‘r. = 7
726 Mm¡.g|.‘r.
IoiʶmMo dH«$ n¥ð>’$i = 103.71 cm2
IoiʶmMo KZ’$i = AY©JmobmMo KZ’$i + e§Hy$Mo KZ’$i
= 3 22 1r r h3 3
=23
22 37
3 13 3cm3
22 37
3 4cmK.g|.‘r.
= 3 3396 264 660cm cm
7 7 7K.g|.‘r.
IoiʶmMo KZ’$i = 94.28 K.g|.‘r.
CXmhaU 4 … VmS>nÌrnmgyZ gH©$gMm V§~y ~Z{dbm Amho Am{U Vmo Imbrb ~mOybm b§~ dVw©imH$ma d¥Îm{MÎmrAm{U darb ~mOybm b§~ dVw©imH$ma e§Hy$À¶m ñdê$nmV Amho. d¥Îm{MÎmrÀ¶m ^mJmÀ¶m V§~yMm ì¶mg Am{U C§MrAZwH«$‘o 126 ‘r. Am{U 5 ‘r. Amho. V§~yMr EHy$U C§Mr 21 ‘r. Amho. Oa Xa ‘r2.Mm VmS>nÌrMm Xa < .15à‘mUo V§~y ~Z{dʶmgmR>r dmnaboë¶m VmS>nÌrMm EHy$U IM© H$mT>m.
CH$b … d¥Îm{MÎmr ^mJ … r =126
2 = 63 ‘r., h = 21 – 5 = 16 ‘r.
l = 2 2r h = 2 263 16
= 3969 256 = 4225
l = 65 ‘r.
EHy$U dmnabobr VmS>nÌr = 14850 Mm¡.‘r.
< .16 Xa Mm¡.‘r. à‘mUo VmS>nÌrMm ¶oUmam IM© = 14,850 × 15 = 2,22,750
VmS>nÌrMm IM© = < 2,22,750
CXmhaU 5 … d¥Îm{MÎmr AmH$mamÀ¶m KZnXmWm©Mr Q>moHo$ AY©dVw©imH$ma AmhoV. Oa KZnXmWm©Mr EHy$U C§Mr 104g|.‘r. Am{U à˶oH$ AY©JmobmH$ma Q>moH$mMr {ÌÁ¶m 7 g|.‘r. Amho. 100 Mm¡.‘r.bm < 4 XamZo ˶mMm n¥ð>^mJCOmim XoʶmgmR>r ¶oUmam IM© {H$Vr?
A B
C
4 cm
3 cm3 cm
g|.‘r.g|.‘r.
4 g|.
‘r.
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Mensuration 399
CH$b … AY©JmobmH$ma ^mJ … r = 7 g|.‘r.
d¥Îm{MÎmrMo ^mJ … r = 7 g|.‘r., h = 104 – (7 + 7) = 90 g|.‘r.
KZnXmWm©Mo EHy$U joÌ’$i = d¥Îm{MÎmr ^mJmMo CSA + 2 × AY©JmobmH$ma ^mJmMo CSA
= 2 rh + 2 × 2 r2 = 2 r (h + 2r)
=22
27
7 90 2(7) cmMm¡.g|.‘r.
= 44 × 104 Mm¡.g|.‘r. = 4576 Mm¡.g|.‘r.
KZnXmWm© TSA = 4.576 Mm¡.g|.‘r.100 Mm¡.Mo ‘r. bm ê$.4 XamZo COmim XoʶmgmR>r ¶oUmam IM©
= 4576 ×4
100`
= < 183.04
KZnXmWm©bm COmim XoʶmgmR>r ¶oUmam IM© = `< 183.04
ñdmܶm¶ 15.5
1. noQ´>mob Q>mH$sÀ¶m XmoÝhr Q>moH$m§Zm g‘mZ {ÌÁ¶oMo AY©Jmob ~g{dbobo AmhoV. Q>mH$sMr EHy$U bm§~r 6 ‘r.Am{U {ÌÁ¶m 1 ‘r. Amho. Va Q>mH$sMr j‘Vm {bQ>a‘ܶo {H$Vr?
2. d¥Îm{MÎmr AmH$mamÀ¶m A{¾~mUmÀ¶m EH$m Q>moH$mbm e§Hy$ Am{U Xþgè¶m Q>moH$mbm AY©Jmob OmoS>bobm Amho.gdmªMr {ÌÁ¶m g‘mZ AgyZ Vr 1.5 ‘r. Amho. A{¾~mUmMr EHy$U bm§~r 7 ‘r. Am{U e§Hy$Mr C§Mr 2 ‘r.Amho. Va A{¾~mUmMo KZ’$i {H$Vr?
3. AY©JmobmH$ma H$n d¥Îm{MÎmrÀ¶m ñdê$nmV Amho. d¥Îm{MÎmr ^mJmMr C§Mr 8 g|.‘r. Am{U H$nmMr EHy$U C§Mr11.5. g|.‘r. Amho. Va H$nmMo EHy$U n¥ð>’$i {H$Vr?
4. dVw©imH$ma d¥Îm{MÎmrÀ¶m AmH$mamÀ¶m gmR>{dʶmÀ¶m Q>mH$sÀ¶m XmoÝhr Q>moH$m§Zm AY©JmobmH$ma ^mJ ~g{dboAmhoV. d¥Îm{MÎmrMm ~mhoarb ì¶mg 1.4 g|.‘r. Am{U bm§~r 8 ‘r. Amho. ~mhoarb ~mOyZo Xa Mm¡.‘r. bm
10 < .à‘mUo a§J bmdʶmgmR>r ¶oUmam IM© H$mT>m.
5. AY©JmobmH$ma e§Hy$ ~g{dboë¶m AmH$mamMo bmH$S>mMo IoiUo Amho. e§Hy$À¶m VimMm ì¶mg 16 g|.‘r.
Am{U C§Mr 15 g|.‘r. Amho. 100 Mm¡.‘r.bm < .7 à‘mUo a§J bmdʶmgmR>r ¶oUmam IM© {H$Vr?
6. gH©$gMm V§~y 3 ‘r. C§Mrn¶ªV d¥Îm{MÎmr AgyZ ˶mdarb e§Hy$À¶m AmH$mamMm Amho. Oa VimMm ì¶mg 105‘r. Am{U e§Hy$À¶m ^mJmMr {VaH$g C§Mr 53 ‘r. Amho. Xa Mm¡.‘r. bm 100 à‘mUo V§~y ~Z{dʶmgmR>rdmnaboë¶m VmS>nÌrMm EHy$U IM© {H$Vr?
eoVmMm AmamIS>m (Scale drawing) :
gnmQ> ^m¡{‘VrH$ AmH¥$˶m§Mo joÌ’$i H$mT>ʶmgmR>r dmnaboë¶m gyÌm{df¶r Amåhmbm ‘m{hVr Amho. Imbr {Xboë¶m
104
cm
90 cm7 cm
7 cm
7 cm
7 cm
g|.‘r
g|.‘r
g|.‘r
g|.‘r
g|.‘r
g|.‘r
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400 UNIT-15
AmH¥$˶m§Mo {ZarjU H$am Am{U ˶m§Mo joÌ’$i H$mT>ʶmÀ¶m gyÌm§Mo ñ‘aU H$am.
.
D b C
h
A
B
S
P
R
b
Ql
K
N
L
h
Mb(a) {ÌH$moU (b) Am¶V (c) g‘m§Va yO Mm¡H$moZ
(A =12 × nm¶m × C§Mr) (A = bm§~r × é§Xr) (A = nm¶m × C§Mr)
A = 1/2 b×h A = l×b A = b×h
A B
EdF
CD
h1
h2
G
D E
Fb
a
h
(d) Mm¡H$moZ (e) g‘b§~ Mm¡H$mZA = 1/2 × H$U© × ~mOy§Mr ~oarO A = 1/2 × C§Mr × g‘m§Va ~mOy§Mr ~oarOA = 1/2 × d (h1+ h2) A = 1/2 h (a + b)
Imbrb AmH¥$˶m§Mo {ZarjU H$am.
B
CA
E D
E D
C
BA
F G
A BC
DE
F
¶m AmH¥$˶m§Mo joÌ’$i H$go {‘iVo?
Amåhr Amnë¶m X¡Z§{XZ OrdZm‘ܶo A{Z¶{‘V AmH$mamZo ~Zboë¶m AmH¥$˶m§À¶m KQ>Zoer OmoS>bobmo AmhmoV.Imbr {Xboë¶m AmH¥$˶m nmhm.
Aem KQ>Zm‘ܶo OoWo AmH¥$˶m‘ܶo {ÌH$moU qH$dm Mm¡H$moZmMo AmH$ma Am{U AmH¥$˶m§Mo A{Z¶{‘V AmH$maAmhoV. gmYo V§Ì åhUOo {Xbobr AmH¥$Vr {ÌH$moU Am{U Mm¡H$moZm‘ܶo {d^mJyZ Z§Va ˶m§Mo joÌ’$i H$mT>Uo.
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Mensuration 401
Aem AmH¥$˶m ‘m{hV Agboë¶m AmH$mam‘ܶo Imbrbà‘mUo {d^mJë¶m OmD$ eH$VmV. ˶m§Mm Aä¶mgH$am.
{ZarjU H$am H$s à˶oH$ AmH¥$Vr {ÌH$moU Am{U g‘b§~ Mm¡H$moZm‘ܶo {d^mJbobr Amho.
Vwåhr H$gm {dMma H$amb H$s, V¶ma Ho$boë¶m doJdoJù¶m {ÌH$moUmMo Am{U g‘b§~ Mm¡H$moZmMo joÌ’$i
dmnê$Z à˶oH$ AmH¥$VrMo EHy$U joÌ’$i H$mT>bo OmVo.
JQ> H$ê$Z dJm©‘ܶo MMm© H$am.
H¥$Vr 1 …
AmboI H$mJX ¿¶m
A C B E D hr n§M ~hþ wOmH¥$Vr aMm.
AB gm§Ym, hr nm¶mMr aofm Amho.
ABbm C, D Am{U E ho b§~ aMm.
F, G, H ¶m q~XþÀ¶m IwUm H$am.
V¶ma Pmbobo {ÌH$moU Am{U g‘b§~ Mm¡H$moZ AmoiIm.
˶m§À¶m ~mOw§Mr bm§~r ‘moOm.
ADF, ACB Am{U EHB ¶m à˶oH$ {ÌH$moUmMo
Am{U g‘b§~ Mm¡H$moZ FHED Mo joÌ’$i H$mT>m.
¶m§À¶m joÌ’$im§Mr ~oarO H$mT>m.
Vwåhr n§M ~hþ wOmH¥$VrMo joÌ’$i H$mT>bo Amho. nydu MMm© Ho$boë¶m BVa AmH¥$˶mgmR>r hr H¥$Vr nwÝhm H$ê$Z
nmhm.
AmVm eoVmÀ¶m VwH$S>çmÀ¶m CXmhaUmMm {dMma H$am. eoVH$ar hm ˶mMm ‘mbH$ Am{U O{‘Z {ZarjH$mbm
˶mMo joÌ’$i H$mT>m¶Mo Amho Ago g‘Oy. Vo H$go Ho$bo OmVo?
O{‘ZrÀ¶m A{Z¶{‘V AmH$mamMo ‘moO‘mn Am{U joÌ’$i H$mT>ʶmgmR>r {ZarjH$mZo dmnaboë¶m nm¶è¶m
Imbrbà‘mUo {Xbo AmhoV.
A{Z¶{‘V AmH$mamMr O‘rZ ‘m{hV Agboë¶m ^m¡{‘VrH$ {d^mJm‘ܶo {d^mJUo.
Jw§Q>g© gmIir (Guntor’s chain) dmnê$Z ~mOy§Mr ‘mno H$mT>Uo.
{ZarjH$mÀ¶m O{‘ZrÀ¶m nwñVH$m‘ܶo ¶m ‘mnm§Mr Zm|X H$aUo.
O 1–1–2–3–4–5X
Y
A
D
E
B
G
F
H
C
2 3 4 5
1
2
3
4
5
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402 UNIT-15
O X
Y
A
D
E
B
G
F
H
C
I1
2
3
4
5
1 2 3 4 5
A{Z¶{‘V AmH$mamMr O‘rZ à‘mUm‘ܶo {MÌ qH$dm
AmH¥$VrV Xe©{dUo.
à˶oH$ I§S>mMo joÌ’$i H$mT>Uo.
à˶oH$ I§S>mÀ¶m joÌ’$imMr ~oarO H$ê$Z O{‘ZrMo EHy$U
joÌ’$i H$mT>bo OmVo.
O{‘ZrÀ¶m Zm|X dhr‘ܶo hr ‘mno H$er KoVmV Am{U Zm|X H$aVmV?
eoVmMm AmamIS>m H$gm H$mT>bm OmVmo? ho g‘OyZ KoʶmgmR>r
Imbrb H¥$Vr H$ê$Z nhm.
H¥$Vr 2 …
J«m’$ (AmboI) H$mJX ¿¶m.
AmH¥$VrV XmI{dë¶mà‘mUo A{Z¶{‘V AmH$ma H$mT>m.
e³¶ VoWo eodQ>À¶m q~XþMr IyU H$am.
àW‘ darb Am{U Imbrb q~XÿMr IyU H$am ˶m‘wio Vo OmoSy>Z nm¶m aofm {‘iVo AB hr nm¶m aofm Amho.
nm¶m aofoÀ¶m XmoÝhr ~mOybm BVa A§Ë¶q~XÿMr IyU H$am. Vo q~Xÿ C,D, E Am{U F AmhoV.
nm¶m aofoda C,D,E Am{U F ho b§~ H$mT>m.
CG, DJ, EK Am{U FG ¶m b§~ aofm AmhoV Ago g‘Oy.
A Am{U C, C Am{U G, D Am{U J, B Am{U F, E Am{U K, D Am{U A OmoS>m.
AmVm Vwåhr ACDBEF hm {Z¶{‘V AmH$ma {‘i{dbobm Amho.
aofm§Mr bm§~r ‘moOm Am{U Imbr {Xboë¶m H$moï>H$m‘ܶo Zm|X H$am.
H$moï>H$m‘ܶo {Xboë¶m qH$‘Vr dmnê$Z H¥$Vr 1 ‘ܶo MMm© Ho$ë¶mà‘mUo joÌ’$i H$mT>m.
O‘rZ gd}jH$mMr O‘rZ ‘moOyZ Zm|X H$aʶmMr nÕV darb à‘mUo MMm© Ho$ë¶mà‘mUoM AgVo. na§Vy ‘mno
gm‘mݶnUo ‘rQ>a‘ܶo AgVmV. ˶m‘wioM H$ƒo {MÌ H$mT>VmZm ¶mo½¶ à‘mU KoVmV Am{U gwadmVrMr (‘wi) ‘mno
˶mà‘mUmZwgma ê$nm§VarV H$aVmV.
AmVm Imbrb CXmhaUm§Mm Aä¶mg H$am.
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Mensuration 403
ñnï>rH$aUmË‘H$ CXmhaUo
CXmhaU 1 … Imbr {Xboë¶m ‘m{hVrdê$Z ßb°Z (AmamIS>m) H$mT>m Am{U joÌ’$i H$mT>m.
CH$b … ¶mo½¶ à‘mU ¿¶m. Vo 20 ‘r. = 1 g|.‘r. g‘Oy.
{Xboë¶m ‘mnm§Mo ê$nm§Va H$am.
200 ‘r. =120 × 200 = 10 g|.‘r.
140 ‘r. =120 ×140 = 7 g|.‘r.
120 ‘r. =120 × 120 = 6 g|.‘r.
40 ‘r. =120 × 40 = 2 g|.‘r.
60 ‘r. =12 × 60 = 3 g|.‘r.
50 ‘r. =12 × 50 = 2.5 g|.‘r.
30 ‘r. =12 × 30 = 1.5 g|.‘r.
C^r aofm AD = 10g|.‘r. (200 ‘r.) H$mT>m.
AD da P, Q, R ho q~Xÿ ¿¶m Ago H$s AP = 2 g|.‘r. (40‘r.), hmoB©b.
AQ = 6 g|.‘r. (120 ‘r.) qH$dm PQ = 4g|.‘r. ( 6-2 KoVbo OmVo)
AR = 7 g|.‘r. (140g|.‘r.) qH$dm QR = 1g|.‘r. ( 7-6KoVbo OmVo)
{Xboë¶m ‘mnmZwgma P,Q, R nmgyZ b§~ H$mT>m.
PB = 1.5 g|.‘r. (30‘r.) QE = 3 g|.‘r. (60‘r.)
RC = 2.5 g|.‘r. (50‘r.)
gd© q~Xÿ OmoS>ë¶mg AB C DE hr AmH¥$Vr {‘iVo
‘mnm§Mr ZmoX H$am.
ABCDE Mo joÌ’$i H$mT>m
ABCDE Mo joÌ’$i = ABP Mo joÌ’$i + g‘b§~ Mm¡H$moZ PBCR Mo joÌ’$i +
CRD Mo joÌ’$i + DEQ Mo joÌ’$i + EQA Mo joÌ’$i.
D n¶ªV ‘r.‘ܶo
200
140 C H$S>o 50
120
40 B H$S>o 30
E H$S>o 60
A nmgyZ
D
C
BP
A
E
R
Q
60
502060
80
30
40
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404 UNIT-15
=12 × AP × PB +
12 ×PR(PB+RC) +
12 × RC× RD+
12 × EQ × QD
12 × EQ × QA
=12 × 40×30 +
12 ×100(30 + 50) +
12 × 50 × 60 +
12 ×60×80+
12 × 60 × 120
= 600 + 4000 + 1500 + 2400 + 3600
ABCD Mo joÌ’$i = 12,100 Mm¡.‘r.
CXmhaU 2 … Zm|X dhrVrb Zm|XrZwgma Imbrb ‘m{hVrMm AmamIS>m H$mT>m Am{U joÌ’$i H$mT>m.
D n¶ªV ‘r.‘ܶo
150100 C H$S>o 70
E H$S>o 80 80
30 B H$S>o 40
A nmgyZ
CH$b … à‘mU 20 ‘r. = 1 g|.‘r.
{ZarjU H$am
AM = 30 ‘r.
AN = 80 ‘r.
MP = (100 – 30) = 70 ‘r.
ND = (150 – 80) = 70 ‘r.
PD = (150 – 100) = 50 ‘r.
(1) ABM Mo joÌ’$i =1 1bh 30 40 600 sq.m.2 2 Mm¡.‘r.
(2) MBCP ¶m g‘b§~ Mm¡H$moZmMo joÌ’$i=1 1h a b 70 70 40 3850 sq.m.2 2 Mm¡.‘r.
(3) DPC Mo joÌ’$i =1 50 70 1750 sq.m.2 Mm¡.‘r.
(4) DEN Mo joÌ’$i =1 80 70 2800 sq.m.2 Mm¡.‘r.
(5) NEA Mo joÌ’$i =1 80 80 3200 sq.m.2 Mm¡.‘r.
ABCDE Mo joÌ’$i=600+3850+1750+2800+3200=12,200 Mm¡.‘r.
E80
P
20
7050
5040
30
A
M B
D
C
N
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Mensuration 405
ñdmܶm¶ 15.6
1. Imbrb ‘m{hVrdê$Z eoVmMm AmamIS>m H$mT>m Am{U eoVmMo joÌ’$i H$mT>m.
C n¶ªV ‘r.‘ܶo
220
D H$S>o 120 210
120 B H$S>o 200
E H$S>o 180 80A nmgyZ
2. O‘rZ gdo©jH$mÀ¶m Zm|X dhrV {Xboë¶m ‘m{hVrdê$Z eoVmMm AmamIS>m H$mT>m. Am{U ˶mMo joÌ’$iH$mT>m.
E n¶ªV ‘r.‘ܶo350
D H$S>o 100 300 F H$S>o 150C H$S>o 75 250
150 G H$S>o 100B H$S>o 50 50
A nmgyZ
3. Imbrb ‘m{hVrdê$Z ABCDEFG Mm H$ƒm AmamIS>m H$mT>m Am{U O{‘ZrMo joÌ’$i H$mT>m.
D n¶ªV ‘r.‘ܶo
225E H$S>o 90 175
125 C H$S>o 20F H$S>o 60 100G H$S>o 15 80
60 B H$S>o 70A nmgyZ
4. Imbr {Xboë¶m AmH¥$Vrdê$Z O{‘ZrMo joÌ’$i H$mT>m. (‘mno ‘rQ>a‘ܶo AmhoV.)
D
40 30
C 35F
E
25
G
30
70
B
A
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406 UNIT-15
ñdmܶm¶ 15.1
1. (i) 176 Mm¡.g|.‘r (ii) 201.14 Mm¡.g|.‘r 2. 3168 Mm¡.g|.‘r 3. 5:4
4. 88Mm¡.‘r.< 3696 5.21,780 Mm¡.g|.‘r. 6. 44 Mm¡.‘r. 7. 5,544 K.g|.‘r.
8. 3432 gm 9. 2 :1 10.3080 K.g|.‘r.
ñdmܶm¶ 15.2
1. 3960 Mm¡.g|.‘r 2. 8 g|.‘r. 3. 7.5 g|.‘r. 4. 7 g|.‘r Am{U 462 Mm¡.g|.‘r 5. 5,500 Mm¡.g|.‘r 6. 4:3 7. 183.33 K.g|.‘r. 8. 3:1 9. 415.8 K.g|.‘r.
10. < 2.068
ñdmܶm¶ 15.3
1. 1408.58 K.g|.‘r. 2. CSA = 1021.42 Mm¡.g|.‘r, TSA = 1335.71 Mm¡.g|.‘r 3. 26148.57 K.g|.‘r. 4. 5 g|.‘r.ñdmܶm¶ 15.4
1. 2,464 Mm¡.g|.‘r 2. 235.71 Mm¡.g|.‘r 3. 20.79 4. 707.14 Mm¡.g|.‘r
5. 1437.33 K.g|.‘r. 6.179.66 K.g|.‘r. 7. 905.14 Mm¡.g|.‘r 8. 22.45 K.‘r.‘r.
9. 5 g|.‘r. 10. 243 ‘r.
CÎmao
Cylinder
Statistics
Cone Frustum ofa cone
Sphere Hemisphere
Combinationof solids
Scaledrawing
2 r(h+r)
r h2
2 rh rl
r (l+r)
r h213
(r +r )1 2
{(r +r )l+1 2
r +r1 22 2 }
2 2
h(r +r +r +r )1 2 1 2
13
4 r2
r343
2 r2
3 r2
r323
LSA
TSA
Mensuration‘mnZo
d¥Îm{MÎmr e§Hy$ ’«$ñQ>‘ e§Hy$ Jmob AY©Jmob
KZ’$i
KZnXmWmªMmg§¶moJ
eoVmMmAmamIS>m
4 r2
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Mensuration 407
When you gain something,
let it be a,
When you make use of it for ntimes,
then it will be na,
When you share it with n persons,
ñdmܶm¶ 15.5
1. 16,761.9 l. 2. 36.53 K.‘r. 3. 253 Mm¡.g|.‘r 4. ` 413.6 5. 58.08 6. < 97.350000
ñdmܶm¶ 15.6
1. 49,300 Mm¡.‘r 2,50625 Mm¡.‘r 3.15,250 Mm¡.‘r 4. 46,00 Mm¡.‘r
*****
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408
n¶m©¶r àíZ ‹( Optional Questions)1.doZ AmH¥$Vr dmnéZ, Imbrb g§~§Y g˶ Amho H$m Vo Vnmgm.
(i) A B = B A (ii) A \ B B \ A
(iii) (A B)I = AI BI (iv)A \ (B C) = (A \ B) (A \ C)
(v) A (B C) = (A B) (A C) (vi)A (B C) = (A B) (A C)
2. doZ AmH$¥$Vr dmnê$Z (A B) (A \ B ) = A ho XmIdm.
3. {Xboë¶m doZ AmH$¥$Vrdê$Z Imbrb qH$‘Vr H$mT>m.
1 (i)n(A B C) (ii) n(A B)
(iii) n(B C) (iv) n(A C)
(v) n(A B C) (vi) n
(vii) n [A
2 Imbrb g§~§Y nS>VmiyZ nmhm.
a. n(A B C) =n (A) +n (B) + n(C)-[n(A B) +n(A C) + n(AC) ]+n(A B C)
b. n (A = n(A B)-n(A B C)
c. n(A B C)1 n n(A B C)
4. \$ŠV doZ AmH$Vr H$mT>y>Z gmoS>dm.
(i) EH m$ dmVm©ha g§KQ>Zobm Ë`mÀ`m 170 J«mhH$mn¡H$s 115 OU XyaXe©Z dmnaVmV, 110 OU ao{S>`mo Am{U130 OU _m{gHo$ dmnaVmV Ago AmT>iyZ Ambo, 85 OU XwaXe©Z Am{U _m{gHo$, 75 OU XwaXe©Z Am{Uao{S>Amo, 95 OU ao{S>Amo Am{U _m{gHo$ Am{U 70 OU {VÝhr dmnaVmV Ago gwÜXm AmT>ibo Va H$mT>m (i)\$ŠV XwaXe©Z {H$Vr OU dmnaVmV? (ii) \$ŠV ao{S>Amo {H$Vr OU dmnaVmV (iii) {H$Vr OU XwaXe©Z Am{U_m{gHo$ dmnaVmV na§Vw ao{S>Amo dmnaV ZmhrV.
CÎma (i) 25 (ii)10 (iii)15
(ii)EH$ eham_Ü o 85% gm`H$b, 40% _moQ>ma JmS`m Am{U 20% H$ma JmS>`m dmnaVmV 32%
gm`H$b Am{U _moQ>ma Jmô`m 13% gm`H$b Am{U H$maJmS`m VgoM 10% _moQ>maJmS`m Am{U
H$ma JmS`m dmnaVmV Va gd© {VÝhr àH$maMr dmhZo dmnaUmè`m bmoH$m§Mr Q>ŠHo$dmar H$mT>m
CÎma 10 %
5. EH$m A. P Mo n{hbo nX 'a' Xþgao nX 'b' Am{U eodQ>Mo nX 'c' Amho Va A. P Mr ~oarO
(a+b) (b+c-2a)2(b-a) ho XmIdm.
576
81
3
24
AU
B
C
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6 .EH$m ‘wbmbm gdm©V darb AmoirV 1 {dQ> Xþgè¶m AmoirV 2, {Vgè¶m AmoirV 3 Am{U B˶mXr ¶mà‘mUo
IoiʶmVrb {dQ>m§Mr {ÌH$moUmH¥$Vr Wßnr aMmd¶mMr Amho. Oa ˶mÀ¶mOdi 100 {dQ>m AmhoV. Va ˶mZo
nyU© Ho$boë¶m AmoitMr g§»¶m Am{U ˶mZo {eëbH$ R>odboë¶m {dQ>m§Mr g§»¶m {H$Vr?
CÎma : 13 Amoir, 9 {dQ>m>
7. EH$m Ioim‘ܶo g‘mZ 6 ’y$Q> A§Vamda Q>monbr Am{U 16 ~Q>mQ>o EH$m gai AmoirV R>odbobo AmhoV. ˶mZo
Q>monbrnmgyZ gamgar 12 ’y$Q> Xa goH§$X doJmZo gwédmV Ho$br. Va EH$m Z§Va EH$ ¶m à‘mUo ~Q>mQ>o Q>monbr‘ܶo
R>odʶmgmR>r IoimSy>§Zm {H$Vr doi bmJob?
CÎma : 136 goH§$X
8. Oa, a,b, c, d ho JwUmoÎma H«$‘mV AmhoV Va {gÜX H$am.
i) (b-c)2 + (c-a)2 + (d-b)2 = (a-d)2 ii) (a-b+c) (b+c+d) = ab+bc+cd
iii) (a+b), (b+c), (c+d) ho gwÜXm G.P. ‘ܶo AmhoV.
9. EH$ CgiUmam M|Sy> ( Bouncing ball) àË oH$doir _mJrb C§MrÀ`m {Zåå¶m C§Mrda nwÝhm CgiVmo
(Rebounds) Oa Ë`mbm 10 _r C§Mrdê$Z Q>mH$bo Va
a) Ë`mdoir O{_Zrbm AmT>iV AgVmZm AmH«${_bobo EHy$U A§Va H$mT>m.
b) pñWa pñWVrbm oÊ`mnydu AmH«${_bobo EHy$U A§Va H$mT>m.
CÎma a) 29.96 $‘r. b) 30 ‘r.
10. XmoZ g§»¶m§Mm A§H$J{UVr ‘ܶ ˶m§À¶m JwUmoÎma ‘ܶmnojm 2 Zo OmñV Amho. Am{U ˶m§Mm JwUmH$maì¶ñV‘ܶ hm ‘moR>çm g§»¶oÀ¶m 1/5 Amho Va ˶m XmoZ g§»¶m H$mT>m. CÎma 9 Am{U 1
11. XmoZ g§»¶m§Mm A§H$J{UVr ‘ܶ Am{U JwUmoÎma ‘ܶ ¶m‘Yrb g§~§Y AM:GM=5:4. Amho. Oa JwUmoÎma ‘ܶ
Am{U JwUmH$ma ì¶ñV ‘ܶ ¶m‘Yrb ’$aH$45- , Amho Va, ˶m g§»¶m H$mT>m. CÎma -2 Am{U-8
12 .Oa 'a' hm b Am{U c, Mm A§H$J{UVr ‘ܶ Am{U 'b' hm a d c, ‘Yrb JwUmoÎma ‘ܶ Amho Va 'c' hm
a Am{Ub ‘Yrb JwUmH$ma ì¶ñV ‘ܶ Amho ho {gÜX H$am.
13. H$moʶm˶mh>r n YZ nyUmªH$mgmR>r n3-n bm 6 Zo ^mJ OmVmo ho {gÜX H$am.
14. H$moUVmhr YZ, g‘ nyUmªH$ hm 4q +1 qH$dm 4q + 3 ñdénmV Amho ho XmIdm, OoWo q hr nyU© g§»¶m Amho.
15. VrZ K§Q>m 4.7 Am{U 17 {‘{ZQ>mZr dmOVmV. Oa gd© VrZ K§Q>m gH$mir 6 dmOVm hmoVAgVrb Va ˶m EH${ÌV
nUo Ho$ìhm dmOVrb ? CÎma 6 dmOyZ 28 {‘ZrQ>.
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410
16. Oa1 19! 10! 11!
nVa n Mr qH$‘V H$mT>m CÎma 121
17 . gai ê$n Úm:( 1)!
( 2)! (n–1)n
n ! CÎma n (n+1)
18. Oa 16 nP3 = 13. n+1P3 Va 'n' H$mT>m. CÎma 15
19. Oa n–1P3 : n+1P3 = 5 : 12 Va 'n' H$mT>m. CÎma 8
20 .Oa 10Pr + 1 : 11Pr = 30 : 11, Va 'r' H$mT>m. CÎma 5
21.n+1Pr+1 = (n + 1) nPr ho {gÜX H$am.
22. Oa nCr-1: nCr: nCr +1 = 3 : 4 : 5, Va r H$mT>m. CÎma 2723.àíZn{ÌHo$‘ܶo 5 àíZ AmhoV. Va EImXm ‘wbJm EH$ qH$dm OmñV àíZ {H$Vr àH$mao gmoS>dy
eH$Vmo? CÎma 3124.EH$m {ZdS>UwH$s‘ܶo 7 C‘oXdma AmhoV ˶mn¡H$s 3 OUm§Mr {ZdS> Ho$br OmD$ eH$Vo. ‘VXmam§Zm 3 nojm OmñV C‘oXdmam§Zm ‘VXmZ H$aVm ¶oUma Zmhr. Va Vo {H$Vr àH$mao ‘VXmZ H$é eH$VmV? CÎma 6325.dVw©imdarb 20 q~XÿVyZ {H$Vr Ordm H$mT>Vm ¶oVmV? CÎma 19026.3 nmoï> noQ>çm (nÌnoQ>çm) ‘ܶo 5 nÌo Q>mH$m¶Mr AmhoV Va {H$Vr àH$mao Q>mH$Vm ¶oVmV, Oa gd©{VÝhr nÌ noQ>çm‘ܶo {H$Vrhr àH$mao nÌo Q>mH$br OmD$ eH$VmV? CÎma 24327.26 B§J«Or ‘wimjao Agbobo H$mS>© (nwÝhm Z KoVm) ì¶dpñWV {ngyZ EH$m nmH$sQ>‘ܶo R>odbr Oa H$mS>© ghOnUo{ZdS>bo Va Imbrb Ajao ¶oʶmMr g§ mì¶Vm {H$Vr?
(i) ñda (ii) 춧OZ
(iii)p Z§Va ¶oUmao Aja (iv) m nydu ¶oUmao Aja
(iv)g Am{U 't' ‘ܶo ¶oUmar Ajao
CÎmao (i) (ii) iii) (iv) (iv)
28. aº$XmZ Ho$boë¶m 60 {dÚm϶mªMo aº$ JQ> Imbrb H$moï>H$mV XmI{dbo AmhoV.
aº$ JQ> A B AB O
{dÚm϶mªMr g§»¶m 16 12 9 23
Oa ghOnUo EH$m {dÚm϶m©Mr {ZdS> Ho$br. Imbrb aº$JQ> ¶oʶmMr g§ mì¶Vm {H$Vr?
(i) A (ii) B (iii) AB (iv) O
(v) B Zmhr (vi) AB Zmhr (vii) A qH$dm AB (viii) B qH$dm O
CÎmao (i) (ii) (iii) (iv) ( v) (vi) (vii) (viii)¥
526
2126
1226
10 26
1226
356 0
166 0
126 0
96 0
236 0
486 0
516 0
256 0
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29. A Am{U B ho XmoZ XmoñV AmhoV. Oa XmoKm§Mmhr dmT>{Xdg ({bn df© Z KoVm)
(i) EH$mM {Xder (ii) doJdoJù¶m {Xder AgʶmMr g§ mì¶Vm {H$Vr?
CÎma (i) (ii)
30. EH$m noQ>rV 12 M|Sy> AmhoV ¶mn¡H$s ‘x’ ho bmb M|Sy> AmhoV. Va
(i) Oa EH$ M|Sy> H$mT>bm Va bmb M|Sy> ¶oʶmMr g§ mì¶Vm {H$Vr?
(ii) Oa noQ>r‘ܶo AmUIr ghm M|Sy> KmVbo Va bmb M|Sy> CMbʶmMr g§ mì¶Vm nyduÀ¶m XþßnQ> AmhoV.Va ‘x’ H$mT>m. CÎma (i) (ii) x = 3
31.Ioim‘ܶo XmoZ ’$mgo AmhoV. Oa ~oarO 2, 3, 4, 5, 10, 11 qH$dm 12 Agob Va Vmo IoimSy> A qOH$Vmo. OaVo 6, 7, 8 qH$dm 9 Agob Va IoimSy> B qOH$Vmo. Va Vwåhr A qH$dm B ho IoimSy> AmhmV? dU©Z H$am.
CÎma IoimSy> B
32. VrZ añVo (‘mJ©) EH$m {R>H$mUr {‘iVmV. EH$m añ˶m§Mo ~m§YH$m‘ Mmby Amho. añ˶m§Mr {ZdS> ghOnUoHo$br. ~m§YH$m‘ Mmby Agboë¶m añ˶m§Mr Am{U ~m§YH$m‘ Mmby Zgboë¶m añ˶m§Mr {ZdS> H$aʶmMrg§ mì¶Vm hr añ˶m§Mo ~m§YH$m‘ Mmby Agboë¶m qH$dm añ˶mMo ~m§YH$m‘ Mmby Zgboë¶mer g‘mZ AgVoho {gÕ H$am.
33 .XmoZ ’$mgo EH${ÌVnUo ’o$H$bo n¥ð>^mJmdarb g§»¶m§À¶m JwUmH$mambm 5 qH$dm 7 Zo ^mJ OmVmo Va ˶m§Mrg§ mì¶Vm H$mT>m. CÎma
34. ghO KS>Umè¶m à¶moJmMm {ZH$mbmMr CËnÎmr ¶eñdr qH$dm A¶eñdr ¶mn¡H$s EH$ Amho. Oa ¶emMrg§ mì¶Vm hr An¶emÀ¶m g§ mì¶VoÀ¶m {VßnQ> Amho. Va ¶emMr g§ mì¶Vm {H$Vr? CÎma
35. ~wÕr~i nwð>m(~moS>©)Vrb VrZ Mm¡ag ghOnUo {ZdS>bo. Va XmoZ Mm¡ag EH$m a§JmMo Am{U EH$ Mm¡ag doJù¶ma§JmMm ¶oʶmMr g§ mì¶Vm {H$Vr? CÎma
36. W§S> hdoÀ¶m (hill station) {R>H$mUr EH$m AmR>dS>çm‘ܶo Zm|X Ho$bobo H$‘rVH$‘r({ZƒÎm‘) Vmn‘mZ
Imbrb à‘mUo {Xbobo Amho.
gmo‘dma ‘§Jidma ~wYdma Jwê$dma ewH«$dma e{Zdma a{ddma4.1 3.2 2.1 1.8 1.6 2.2 1.4
ì¶Ë¶mg Am{U à‘m{UV {dMbZ H$mT>m Am{U {ZH$mbmMo ñnï>rH$aU H$am. CÎma v =0.805, =0.897
37. Imbrb dma§dmaVm {dVaU gmaUrdê$Z (i) A§H$J{UVr ‘ܶ (ii) à‘m{UV {dMbZ H$mT>m.
C.I 20-25 25-30 30-35 35-40 40-45 45-50f 8 3 15 12 8 4
CÎma ‘ܶ = 34.6, =7.286
364365
x12
1365
34
1136
1621
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38. Imbrb {ÌÁ¶m§Va I§S>mboImMm Aä¶mg H$am Am{U ˶mImbrb àíZm§Mr CÎmao Úm.
‘mZdr earamVrb KQ>H$m§Mr (g¶y§JmMr) Q>¸$odmar
(i)EHy$U ‘mZdr earamÀ¶m dOZmer g‘mZ AgUmè¶m ‘mZdr
earamÀ¶m ËdMoVrb à{WZm§Mr Q>¸o$dmar {H$Vr?
(ii) 50 {H$.J«°. dOZmÀ¶m EH$m 춺$sÀ¶m earamVrb nmʶmMo à‘mU {H$Vr?
(iii)ñZm¶y‘Yrb à{WZmÀ¶m {d^mJUrMo hmS>m§‘Yrb à{WZm§À¶m {d^mJUrer JwUmoÎma {H$Vr?
(iv) ‘mZdr earamVrb H$moUVm ^mJ hmS>o Am{U ËdMm ¶mnmgyZ ~Zbobm Zmhr.
(v)‘mZdr earam‘ܶo à{WZm§Mr {d^mJUr Am{U BVa dmibobo KQ>H$ Xe©{dʶmMm H|$ÐñW H$moZ {H$Vr?
CÎma i) 1.6 % (ii) 35 {H$.J«° (iii) 2:1 (iv) 415 (v) 1080
39. nwñVH$m§À¶m àXe©Zm‘ܶo ¶oUmè¶m IMm©À¶m {dVaUmMr Q>¸$odmar Xe©{dUmam {ÌÁ¶m§Va I§S>mboI ~mOybm
{Xbobm Amho. {ÌÁ¶m§Va I§S>mboImMm Aä¶mg H$am Am{U àíZm§Mr
CÎmao Úm.
(i) Oa EHy$U ¶oUmam IM© <3,60,000 Amho. Va à˶oH$ dñVybm
¶oUmam IM© {H$Vr?
(ii) Oa H$m§hr nwñVH$mÀ¶m ‘wÐUmb¶mMm IM© < 30,600 àH$meH$mZo
{Xbm nm{hOo Va ˶m nwñVH$m§Zm {Xbobo ‘mZYZ {H$Vr?
(iii) nwñVH$m§Mo ‘mZYZ ho H$mJXmÀ¶m Xamnojm {H$Vr Q> o$ H$‘r Amho.
(iv) nwñVH$ ~m§YUrMm IM© hm XiUdiU (dmhVyH$) IMm©À¶m {H$Vr
Q> o$ OmñV Amho.
(v) Oa dmhVyH$ IM© <36,600 Amho Va nwñVH$ ~m§YUr IM© {H$Vr?
(vi) Oa ‘wÐUmb¶mbm ¶oUmam IM© <52,600 Amho Va nwñVH$ ~m§YUr IM© hm ‘wÐUmb¶ IM©mnojm {H$VrZo H$‘r
Amho.
Binding20%
Transport10%
Paper cost25%
Royalty15%
Printingcost
20%
Adverti-
semen
t10% ‘wÐU IM©
Om[hamVr
‘mZYZ
OmoS>H$m‘ H$mJXmMm IM©
XiU diU
Water70%
Proteins
Other dryelements 14%
16%Bones
Skin
MusclesHormonesandEnzymes
110
25
61
31
{dH$ao Am{Ug§àoaHo$
ñZm¶y
ËdMmhmS>o
nmUrà{WZo
BVa H$moaS>oKQ>H$
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(vii) Oa <5500 nwñVH$m§Mo àH$meZ H$aʶmV Ambo Am{U ˶mgmR>r dmhVyH$ IM© < 82,500 Pmbm Va
àH$meH$mbm 25% Z’$m hmoʶmgmR>r nwñVH$m§Mr {dH«$sMr qH$‘V {H$Vr?
(viii) nwñVH$mMr qH$‘V IaoXr qH$‘VrÀ¶m 20% Zo dmT>{dbr. Oa nwñVH$mMr N>m{nb qH$‘V < 180 Amho Va
EH$m nwñVH$mgmR>r dmnaboë¶m H$mJXmMr qH$‘V {H$Vr?
CÎma o XiUdiU = <36,000 ; H$mJX IM© = < 90,000; OmoS>H$m‘ = < 72,000;‘mZYZ = <54,000; Om{hamV = < 36,000, N>nmh© = < 72,000, (ii) ‘mZYZ = <22, 950(iii) 10% (iv) 10% (v) OmoS>H$m‘ = < 73,200 (vi) 0 (vii) {d.{H$ = <187.50 (viii) <37.5
40. Oa y =+ - -+ + -
x a x ax a x a
Va1 2
+ =x
yy a Ago XmIdm.
41.eof à‘o¶ dmnê$Z ~mH$s H$mT>m. p(x) = 3x4 + 2x3 –2
3x
–9x
+227
g(x) = x +23
CÎma r (x) = 0
42. Oa p(x) = x4 – 2x3 + 3x2 – ax + b hr Aer ~hþnXr Amho H$s {Vbm (x + 1) Am{U (x – 1), Zo ^mJboAgVm ~mH$s AZwH«$‘o 19 Am{U 5 amhVo. p(x) bm (x–2) Zo ^mJbo AgVm ~mH$s H$mT>m.
CÎma 10
43. Oa , (x + 2) hm (4x4 + 2x3 – 3x2 + 8x + 5a) Mm A d¶d Agob Va a Mr qH$‘V H$mT>m. CÎma a = - 4
44. (x4 + ax3 + 2x2 – 3x + b) bm (x2 – 1) Zo ^mJ OmVmo Va a Am{U b Mr qH$‘V H$mT>m. CÎma a = 3,b=- 3
45. x3 – 2x2 –12x – 9 ‘ܶo H$m¶ {‘i{dbo AgVm x2 + x – 6 Zo nyU©nUo ^mJ OmB©b ?CÎma 3x +27
46. 2x3 + 3x2 – 22x + 12 ‘ܶo H$m¶ {‘i{dbo AgVm n[aUm‘r ({‘iUmè¶m) ~hþnXrbm (2x2 + 5x – 14)
Zo nyU©nUo ^mJ OmB©b ? CÎma 3x + 247. x3 – 6x2 – 5x + 80 ‘YyZ H$m¶ dOm Ho$bo AgVm n[aUm‘r ({‘iUmè¶m) ~hþnXrbm x2 + x – 12 Zo nyU©nUo^mJ OmB©b? CÎma 14 x - 448. Oax + a hm Imbrb à˶oH$s XmoÝhr ~hþnXtMm Ad¶d Amho Va a Mr qH$‘V H$mT>m.
(i) x3 + ax2 – 2x + a + 4 (ii) x4 – a2x2 + 3x – a CÎma (i) a= - 4 3 (ii) a=0
49. Imbrb dJ© g‘rH$aUo nyU© dJ© H$ê$Z gmoS>dm.
(i)3x (x – 5) = 2x(x + 7) (ii)5 7
1xx
= 3x + 2
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(iii) a2x2 – 3abx + 2b2 = 0 (iv) 4x2 + 4bx – (a2 – b2) = 0
CÎmao (i) 29, 0 (ii) 3, –1 (iii)2b ba a
, (iv)_b a
2
50. gyÌmMm Cn¶moJ H$ê$Z Imbrb dJ© g‘rH$aUo gmoS>dm.
i.x2 – 7x + 12 = 0 ii.p = 5 – 2p2 iii. 4x2 – 4ax + (a2 – b2) = 0
iv. 2 9 13x x v . 36x2 – 12ax + (a2 – b2) = 0 vi.1 1 1 0
2 3 4x x x
vii.3 2 8
5 4 2b b b
CÎma o i) 4, 3 ii)41-1
4 iii)
b
2
aiv) 20, 8 v)
b
6
a vi)
39
3vii )
58
13, 2
51. ‘moR>çm Mm¡agmÀ¶m joÌ’$imVyZ bhmZ Mm¡agmÀ¶m joÌ’$imMr XþßnQ> dOm Ho$ë¶mg CÎma 14 Mm¡.g|.‘r. ¶oVo.VWm{n Oa ‘moR>çm Mm¡agmÀ¶m joÌ’$imÀ¶m XþßnQ>rV bhmZ Mm¡agmÀ¶m joÌ’$imMr {VßnQ> {‘i{dë¶mg CÎma203 Mm¡.g|.‘r. ¶oVo. XmoÝhr Mm¡agm§À¶m ~mOy AmoiIm. CÎma 5 g|.‘r., 8 g|.‘r.
52. . EH$ H$U O{‘Z nmVirnmgyZ àjo{nV Ho$bobm Agm Amho H$s O{‘ZrnmgyZ ˶mMr C§Mr t goH§$XmZ§Va
(20t – 5t2) ‘r. Agob. {H$Vr goH§$XmZ§Va O{‘ZrnmgyZ 15 ‘r. C§Mrda H$U Agob? VoWo XmoZ CÎmam§Mre³¶Vm Amho? ¶m~Ôb Vwåhr WmoS>³¶mV dU©Z H$am. CÎma 3 qH$dm 1
53. C1 Am{U C2 dVw©io EH$‘oH$m§Zm A ‘ܶo Am§Vañne© H$aVmV Am{U C1 dVw©imMr AB Ordm C2
bm P ‘ܶo N>oXVo. Va {gÕ H$am H$s AP = PB.
54 . ABC À¶m BC ~mOybm EH$ dVw©i P ‘ܶo ñne© H$aVo. AB Am{U AC dmT>{dë¶m AgVm ˶mdVw©imbm AZwH«$‘o Q Am{U S ‘ܶo ñne© H$aVmV. {gÕ H$am H$s AQ=1/2 ( ABC Mr n[a{‘Vr)
55 .Imbrb à˶oH$ AmH¥$˶m‘Yrb ‘m{hV Zgboë¶m qH$‘Vr H$mT>m. gd© bm§~r g|Q>r‘rQ>a‘ܶo {Xë¶m AmhoV. (‘mno
à‘mUmV Zm§hrV)
CÎma (i) x = 4, y = 9 (ii) x = 2.64 , y = 2 0.96 (iii) a = 9, b = 3
OOI
A
P
B
C2
C1
A G
FCB
D E
x
y
8 6
24
(i )i
M
N Q
P
LK
SR xy
z
3
5
4
6
D
G
FK
H
J
E
b
b
a
5 7
(ii) (iii)
8
12
62i
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O
A B
CD
E F
56. "'‘ܶ q~XÿÀ¶m à‘o¶mMr"" OmVrà{Vkm gm§Jm.WoëgMm ì¶Ë¶mg à‘o¶ dmnê$Z {gÜX H$am.
57.ABCD Agm Mm¡H$moZ Amho Á¶m ‘ܶo W, X, Y Am{U Z AZwH«$‘o AB,
BC, CA Am{U DA ~mOy§Mo {Ì^mOH$ q~Xÿ AmhoV. {gÕ H$am WXYZ
g‘m§Va wO Mm¡H$moZ Amho.
(gyMZm : A, C OmoS>m)
58.ABCD Agm g‘b§~ Mm¡H$moZ Amho H$s Á¶m‘ܶo AB || DC H$U© 'O' ‘ܶo
N>oXVmV. Ago XmIdm H$sAO COBO OD (‘y.à.à‘o¶ dmnê$Z {gÕ H$am)
(gyMZm: 'O' ‘YyZ EF || AB || CD H$mT>m.)
59. ABCD hm g‘ê$n Mm¡H$moZ Amho. BC da 'P' hm H$moUVmhr
q~Xÿ Amho. AP OmoS>br Am{U Aer dmT>{dbr H$s
DC dmT>dyZ Vr Q ‘ܶo {‘iVo.
{gÕ H$am1 1 1
BC PC CQ= -
60. Oa {ÌH$moUmÀ¶m VrZ ~mOy§Mo ‘ܶq~Xÿ H«$‘mZo OmoS>bo Va [gÕ H$am H$s V¶ma hmoUmao Mma {ÌH$moU
EH$‘oH$m§er g‘ê$n Am{U ‘yi {ÌH$moUmerhr g‘ê$n AgVmV.
61.{gÕ H$am H$s XmoZ g‘ê$n {ÌH$moUm§À¶m joÌ’$im§Mo JwUmoÎma ho ˶m§À¶m g§JV ‘ܶJm§À¶m JwUmoÎmamÀ¶m
dJm©BVHo$ AgVo.
62. A A H$gmoQ>r dmnê$Z q^Jo qH$dm AmaemMo gyÌ aMm.
63.H$mQ>H$moZ {ÌH$moUmÀ¶m ~mOyda g‘ wO {ÌH$moU H$mT>bo AmhoV.
Ago XmIdm H$s H$Um©darb {ÌH$moUmMo joÌ’$i ho BVa XmoZ ~mOydarb
{ÌH$moUm§À¶m joÌ’$im§À¶m ~oaOoBVHo$ AgVo.
64. g‘b§~ Mm¡H$moZmMo joÌ’$i dmnéZ nm¶W°Jmoag à‘o¶ {gÜX H$am.
A B
CD
P
Q
M
D
P
N
F C A
B
A
B
2 234
+x yA
B C
R
P
Q
x
y
234x
234
y
xy
2
2
+
A
E
B DC
a
cb
a c
A B
CD
1
1
1
1
2
2
2
x
y
z
w 2
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65. ABC ‘ܶo, (i) ACBACB = 60° (ii) AD BC. VaAC Am{U BC. Mo AB gmR>r 춺$ H$éZ {dYmZ {‘idm
66. ABC ‘ܶo, H$U© hm XmoZ ~mOy§n¡H$s EH$m ~mOynojm 2 EH$H$ Zo ‘moR>m Am{U Xþgè¶m ~mOyÀ¶m XþßnQ>rnojm1 EH$H$ Zo A{YH$ Amho. ~mOyMr ‘mno H$mT>m.
CÎmao AB =15 EH$H$ BC = 8 EH$H$ AC = 17 EH$H
67. H$mQ>H$moZ {ÌH$moUmÀ¶m ~mOy A§H$J{UVr loUr‘ܶo AmhoV.H$s {ÌH$moUmÀ¶m ~mOy 3 : 4 : 5.JwUmoÎmamV AmhoVAgo XmIdm .
68. LAB‘ܶo, ALB 90Ð = ° Am{U LM AB
{gÜX H$am2
2
LA AMLB AB
=
69. Oa 2 sin2 + 5 cos = 4. Va cos =12 Ago XmIdm
70.sin cos
1cosec sec
ho {gÕ H$am.
71. Oa x = r sin A cos B, y = r sin A sin B, z = r cos A, Va x2+y2+z2=r2. ho {gÜXH$am.
72.XmoZ {ZarjH$ EH$‘oH$mnmgyZ 1 {H$‘r Xÿa AgyZ EH$mM b§~àVbm‘ܶo ’w$Jm åhUyZ AmhoV. na§Vw ˶mÀ¶m
{dê$Õ ~mOyg 60° Am{U 45° Ago Cƒ nmVirVrb H$moZ {XgyZ ¶oVmV. ’w$Jm O{‘ZrnmgyZ {H$Vr
C§Mrda Amho? CÎmao3
1 3{H$bmo ‘rQ>a
73.XrnJ¥hmnmgyZ XrnJ¥hmÀ¶m {dê$Õ ~mOyg AgUmè¶m XmoZ OhmOm§Mo {ZÀM nmVirVrb H$moZ 450 Am{U
600 Agë¶mMo {XgyZ ¶oVo. Oa XrnJ¥hmMr C§Mr 120 ‘rQ>a Am{U XmoZ OhmOmZm OmoS>Umar aofm
XrnJ¥hmÀ¶m nm¶mVyZ OmVoo, XmoZ OhmOm‘Yrb A§Va H$mT>m. CÎmao 120
L
MA B
A
B CD
E
60°
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113 ‘rQ> a
74. ‘r. Imob H$mT>boë¶m {dhrarMm AmVrb ì¶mg 10 ‘r. Amho. {dhrarVyZ H$mT>boë¶m
‘mVrMm 5 ‘r. é§XrMm ^amd Q>mH$bm. Va ˶m ^amdmMr C§Mr H$mT>m.
CÎma h = 4.66 ‘r.
75.PmS>mMr ’$m§Xr d¥Îm{MÎmr AmH$mamMr Amho. ˶mMm n[aK 176 g|.‘r. Amho. Oa ’$m§XrMr bm§~r 3 ‘r. Amho.Va ˶m ’$m§XrnmgyZ {‘i{dboë¶m bmH$S>mMo KZ’$i H$mT>m.
CÎma 7,39,200, K.g |.‘r.76.14 ‘r. ì¶mg Am{U 8 ‘r. Imob {dhra ImoXbr. ¶m‘YyZ H$mT>boë¶m ‘mVrMm g^modVmbr 21 ‘r OmS>rMm
^amd Q>mH$bm Va ^amdmMr C§Mr H$mT>m. CÎma 0.53 ‘r.77.EH$m JmdmVrb OÌo‘ܶo XþH$mZXmamZo d¥Îm{MÎmr AmH$mamÀ¶m VimMr {ÌÁ¶m 15 g|.‘r. Agboë¶m ^m§S>çm‘ܶo
32 g|.‘r. C§Mrn¶ªV g§Í¶mMm ag ^ê$Z R>odbm. ˶mZo Vmo 3 g|.‘r. {ÌÁ¶m Am{U 8 g|.‘r. C§M Agboë¶m
d¥Îm{MÎmr AmH$mamÀ¶m ½bmg‘YyZ à˶oH$s <.3 ¶mà‘mUo {dH$bm. Vmo ag nyU©nUo {dHy$Z ˶m XþH$mZXmamZo
{H$Vr ê$n¶o {‘i{dbo? CÎma < 30078. ^ard e§Hy$Mm ì¶mg 14 g|.‘r. Am{U b§~ C§Mr 51 g|.‘r. Amho. Á¶m nXmWm©nmgyZ Vo ~Zbobo Amho ˶mMo
dOZ 10 J«°‘/K.g|.‘r. Va ˶mMo dOZ H$mT>m. CÎma 26.18 {H$.J °.79. b§~ dVw©imH$ma e§Hy$Mr C§Mr 3.6 g|.‘r. Am{U ˶mÀ¶m VimMr {ÌÁ¶m 1.6 g|.‘r. Amho. Vmo {dViyZ 1.2
g|.‘r. {ÌÁ¶oMm b§~ dVw©imH$ma e§Hy$ ~Z{dʶmV Ambm. Va Aem [aVrZo V¶ma Pmboë¶m e§Hy$Mr C§Mr H$mT>m. CÎm a 6.4 g |.‘r .
80.e§Hy$ AmH$mamMm M§~y nmʶmZo nyU©nUo ^abobm Amho. M§~yÀ¶m VimMr {ÌÁ¶m 'a' Am{U C§Mr '2a' Amho. ho nmUr23a
VimÀ¶m d¥Îm{MÎmr AmH$mamÀ¶m M§MwnmÌm‘ܶo AmoVbo. d¥Îm{MÎmr AmH$mamÀ¶m M§MwnmÌmVrb nmʶmMr
C§Mr H$mT>m. CÎma 3 2a
81. YmVyÀ¶m nͶmnmgyZ ~Z{dbobo ^m§S>o darb Q>moH$mda CKS>o AgyZ ’«$ñQ>‘ e§Hy$À¶m AmH$mamMo Amho. ˶mMr C§Mr16 g|.‘r. Am{U darb Am{U Imbrb Q>moH$m§À¶m {ÌÁ¶m 20 g|.‘r. d 8 g|.‘r. AmhoV. ^m§S>o XþYmZo nyU©nUo^aʶmgmR>r ê$.40 Xa {bQ>aà‘mUo ¶oUmam IM© H$mT>m. 100 Mm¡.‘r.bm ê$.8 à‘mUo YmVy nͶmnmgyZ ^m§S>o
~Z{dʶmgmR>r ¶oUmam IM© H$mT>m. ( = 3.14 ¿¶m) CÎma < 418, < 156.7582. YmVyÀ¶m M|Sy>Mm ì¶mg 3.5 g|.‘r. Amho. Oa YmVyMr KZVm 8.9 g/Mm¡.g|.‘r. Amho. Va M|Sy>Mo dOZ H$mT>m.
(gyMZm … dñVw‘mZ = KZ’$i × KZVm) CÎma 199.8 J°.83.^ard AY©JmobmH$ma ‘oUmMr {ÌÁ¶m 12 g|.‘r. Amho. Vmo {dVidyZ 6 g|.‘r. VimMr {ÌÁ¶m Agbobm e§Hy$
~Z{dbm. Va e§Hy$Mr C§Mr H$mT>m. CÎma 96 g|.‘r.84.YmVyÀ¶m JmobmH$ma e§ImMr AmVrb Am{U ~mhoarb {ÌÁ¶m AZwH«$‘o 4 g|.‘r. d 8 g|.‘r. Amho. ˶mbm
{dVidyZ b§~ dVw©imH$ma d¥Îm{MÎmr ~Z{dʶmV Ambr {VMr C§Mr1
93
g|.‘r. Amho. Va d¥Îm{MÎmrÀ¶mVimMm ì¶mg H$mT>m. CÎma 16 g|.‘r.
85. 28 g|.‘r. ì¶mgmMm ^ard Jmob {dVi{dbm Am{U ì¶mg243
g|.‘r. d C§Mr 3 g|.‘r. Agbobo AZoH$
5m5m5m
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nwadUr (Appendix)
J{UVr Z‘yZo (Mathematical Modelling)
Amnë¶m {Z˶ OrdZmVrb KQ>Zm Am{U dmñV{dH$ OJm‘ܶo Amnë¶mbm AZoH$ g‘ñ¶m§Zm Vm|S> Úmdo bmJVAmho, ˶mda J{UV Vk, d¡km{ZH$, AW©emñÌk, ‘mZgmonMma Vk Am[U BVam§Zr Cnm¶ emoYbo AmhoV.
Imbrb CXmhaUm§Mm Aä¶mg H$am.* nmohMy Z eH$Umè¶m {eIam§Mr C§Mr H$mT>Uo.* g‘wÐ Am{U ZÚm ¶m§Mr Imobr emoYUo.* 10 dfm©Z§Va eha qH$dm amîQ´>m§À¶m bmoH$g§»¶oMr ^{dî¶dmUr H$aUo.* gy¶m©À¶m n¥îR>^mJmdarb Vn‘mZmMm A§XmO H$aUo.* ‘§Ji J«hmda CnJ«h gmoS>Uo.* CnJ«hmÀ¶m ghmæ¶mZo g§nH©$Omb ( ) V¶ma H$aUo.
Aem gd© dmñV{dH$ OJmVrb g‘ñ¶m gmoS>{dʶmgmR>r Or g§H$ënZm dmnabr OmVo {Vbm "J{UVr Z‘yZo 'åhUVmV.J{UVr Z‘yZo åhUOo H$m¶?
J{UVr Z‘yZo ho X¡Z§{XZ OrdZmVrb H$mhr KQ>Zm§Mo J{UVr dU©Z H$aVo. J{UVr Z‘yZo V¶ma H$aʶmMr hr à{H«$¶mAmho Am{U {VMm Cn¶moJ H$éZ g‘ñ¶m§Mo n¥W:H$aU H$éZ ˶m gmoS>rdë¶m OmVmV.
J{UVr Z‘yZo qH$dm à{VH¥$Vr hr J{UVr g§H$ënZm Am{U ^mfm dmnéZ dU©Z H$aʶmMr nÜXV Amho.J{UVr Z‘yݶm§À¶m {dH$mgmÀ¶m à{H«$¶obm J{UVr Z‘yZo åhQ>bo OmVo. J{UVm‘ܶo J{UVr Z‘yݶm§Mm dmna ¶mgmR>r
Ho$bm OmVmo.* dmñV{dH$ OJmVrb JwUY‘mªMo dU©Z H$aʶmgmR>r,* dmñV{dH$ OJmVrb KQ>Zm§{df¶r ‘hËdmMo àûZ VnmgʶmgmR>r,* J{UVr ñdénmVrb dmñV{dH$ OJmVrb JwUY‘mªÀ¶m ñnîQ>rH$aUmgmR>r,* J{UVr nÜXVrZo ¶w³Ë¶m§Mr MmMUr H$aʶmgmR>r,* dmñV{dH$ OJmVrb ^{dî¶dmUr H$aʶmgmR>r,
dmñV{dH$ OJmVrb Xe©{dbobo J{UVr Z‘yZo {Xboë¶m àdmhrV V³Ë¶m‘Yrb joÌm§er g§~§{YV AmhoV.
J{UVr Z‘yZo ho da gm§{JVboë¶m gd© joÌ, ˶m§Mo CnjoÌ Am{U kmZmÀ¶m gd© emIm‘ܶo dmnaVmV.
dmñV{dH$ OJmMm g§X^©
ewÜX{dkmZ
g‘mO{dkmZ
eoVr ì¶dgm¶ Ioig§~§{YV{dkmZ
^m¡{VH$emñÌ agm¶ZemñÌ OrdemñÌ g‘mOemñÌ AW©emñÌ n[ag§ñWm
Am¡fYA{^¶m§{ÌH$s hdm‘mZemñÌO¡{dH$ agm¶ZemñÌ
Oݶy A{^¶m§{ÌH$s O¡{dH$ V§ÌkmZ
gyú‘OrdemñÌ
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Imbr {Xboë¶m AmH¥$Vr‘ܶo J{UVr Z‘wݶm§À¶m {H«$¶m Xe©{dboë¶m AmhoV.
J{UVr Z‘wݶm§Mr à{H«$¶m hr Imbrb n[aUm‘H$maH$ Am{U H«$‘dma nm¶è¶m‘ܶo Ho$br OmVo.J{UVr Z‘wݶm§À¶m nm¶è¶m :nm¶ar 1 : g‘ñ¶m§Mo AmH$bZ
¶m nm¶ar‘ܶo dmñV{dH$ OJmVrb g‘ñ¶m à˶jnUo g‘OyZ KoD$Z H$mht KQ>H$ Am{U J¥hrVH$mÛmao ˶m§Mr ì¶m»¶mAm{U ñnîQ>rH$aU H$aUo.CXmhaUmW© : A^¶maʶmVrb dZñnVtÀ¶m g§»¶oMm A§XmO H$aUo, Oo à˶jmV ‘moOUo e³¶ Zmhr.gm‘mݶnUo O§JbmÀ¶m joÌmMm Z‘wZm {dMmamV KoVbm Va Am{U O§JbmVrb EHy$U PmS>m§À¶m g§»¶oMm A§XmO Ho$bm OmVmo.nm¶ar 2 : J{UVr Z‘wݶmMo gyÌrH$aU
J{UVr nXo, KQ>H$ Am{U J¥hrVm§Mr {ZdS> H$éZ dmñV{dH$ OJmVrb g‘ñ¶m§er g§~§Y àñWm{nV H$éZ Xe©{dUo.J{UVr nXo Am{U ^mfo‘ܶo J{UVr Z‘wZo {dH${gV H$aUo Am{U ˶m§Mo dU©Z H$aUo. J{UVr Z‘wݶm§Mo dU©Z H$aʶm§Mo H$mhràH$ma :* Mbm§Mr ì¶m»¶m H$aUo.* gm‘wJ«r g§J«{hV H$éZ H$moîQH$mV ‘m§S>Uo.* g‘rH$aUo Am{U gyÌo aMUo.* AmboI H$mT>Uo.CXmhaUmW© : O§JbmVrb EHy$U PmS>m§À¶m g§»¶oMm A§XmO H$aʶmgmR>r J{UVr Z‘wZo {dH${gV H$aUo.O§JbmMo joÌ’$i 100 Mm¡. {H$. ‘r. Amho Ago g‘Oy. Vo VrZ àH$maÀ¶m joÌmV {d^mJbo OmVo.A KZXmQ> PmS>m§Zr ì¶mnbbo joÌB >{dai PmS>m§Zr ì¶mnbbo joÌC KZXmQ> qH$dm {dai ¶mn¡H$s H$moU˶mhr PmS>mZr Z ì¶mnbobo joÌ
g§nyU© O§Jb à˶oH$r Aܶm© {H$.‘r. à‘mUo 200 ^mJm‘ܶo {d^mJbo Ago ‘mZy. ho à‘m{UV AmamIS¶m‘ܶo ZH$memXe©dyZ H$aVm ¶oVo. 200 ^mJmn¡H$s à˶oH$ ^mJMr g§µ»¶m emoYbr OmVo Am{U A:B:C=3:1:2 ho JwUmoÎma {‘iVo.
Ago g‘Om H$s 12 ^mJ ¶mÑpÀN>H$ à¶moJmZo {ZdS>bo, Á¶m‘ܶo A àH$maMo 6, B àH$maMo 2 Am{U C àH$maMo 4AmhoV. ¶m 12 ^mJmVrb Pm§S>mZm g§»¶m XodyZ ‘moObo OmVo. hr gm‘J«r n¥W:H$aUmgmR>r KoVbr OmVo.nm¶ar 3: J{UVr g‘ñ¶m§Mo {ZdmaU
doJdoJir J{UVr V§Ìo dmnê$Z nm¶ar 2 ‘Yrb J{UVr Z‘wݶmZm gaiê$n XodyZ gmoS>{dUo.CXmhaUmW©, {ZdS>boë¶m à˶oH$ 12 ^mJmVrb PmS>m§Mr g§»¶m ‘moOyZ Pmë¶mZ§Va PmS>m§À¶m g§»¶oMr gamgar H$mT>bo OmVo.
g‘Om H$s. 12 ^mJmVrb PmS>m§Mr gamgar g§»¶m 3556 Amho.Vo§ìhm, EH$m ^mJmVrb PmS>m§Mr gamgar g§»¶m 3556/12= 296 Amho.
nm¶ar 4: Cnm¶ qH$dm CH$bmMo ñnîQ>rH$aU:nm¶ar 3 ‘ܶo {‘i{dboë¶m CH$bm§Mo AmVm dmñV{dH$ OJmVrb KQ>Zm qH$dm g‘ñ¶m§Mo ñnîQ>rH$aU Ho$bo OmVo.
åhUOoM, dU©Z [Xbr OmVmV Am{U g‘ñ¶m§À¶m {ZdmaUm{df¶r ^{dî¶dmUr H$obr OmVo.CXmhaUmW©, nm¶ar 1 ‘Yrb g‘ñ¶m§Mo nwZ:n[ajU H$aUo Am{U CH$b dmnaUo. åhUOoM 100 Mm¡. {H$.‘r. ‘Yrb O§JbmVrbEHy$U PmS>m§Mr g§»¶m hr A§XmOo 59,200 Amho.
dmñV{dH$ OJmVrb g‘ñ¶m§Mo {ZdmaU J{UVr Cnm¶
gyÌrH$aU J{UVr g‘ñ¶mdmñV{dH$ OJmVrb g‘ñ¶m
ñnîQ>rH$aUMmM
Ur
n¥W:H
$aU
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nm¶ar 5 : Z‘wݶm§Mo à‘mUrH$aUnm¶ar 3 ‘ܶo {‘i{dbobo {ZH$mb Am{U nm¶ar 4 ‘Yrb ñnîQ>rH$aUmMr VnmgUr H$ê$Z ˶mbm AW© bmJVmo H$m Vo
nmhVmV. Omo n¶ªV J¥hrVo ~XbVmV qH$dm ZdrZ ‘m{hVr {‘iVo qH$dm Z‘wZo V¶ma hmoVmV Vmo n¶ªV Z‘wZo dmnaVmV.n¶m©¶r Z‘wZm :
g‘Om H$s O§JbmMo hdoVyZ N>m¶m{MÌ KoVbo Am{U {MÌm‘Yrb à˶oH$ PmS> EH$m {Q>§~mUo Xe©{dbo.PmS>m§Mr g§»¶m {‘i{dʶmgmR>r Z‘yZm {dH${gV H$am.J{UVr Z‘yZo {‘i{dʶmgmR>r ì¶dhmar J{UVm‘YyZ AmUIr EH$m CXmhaUmMm {dMma H$ê$.
CXmhaU. amOoebm gm¶H$b IaoXr H$am¶Mr Amho.Vmo XwH$mZmV OmVmo Am{U < 1800 qH$‘VrMr gm¶H$b {ZdS>Vmo ˶mÀ¶mOdi< 600 AmhoV. XþH$mZXmamZo ˶mÀ¶m nwT>o hßVo~§XrZo IaoXr H$aʶmMr ¶moOZm Imbrbà‘mUo {Xbr.
amOoe < 600 hr a³H$‘ IaoXrÀ¶mdoir XoVmo Am{U am{hbobr a³H$‘ à˶oH$s <610 Mo XmoZ ‘m{gH$ hßVo XodyZ IaoXrH$ê$ eH$Vmo. amOoeH$S>o XmoZ àñVmd AmhoV, EH$ Va Vmo hßVo~§Xr ¶moOZonm’©$V IaoXr qH$dm 10 % dm{f©H$ gai ì¶O XamZo~±Ho$H$Sy>Z H$O© KodyZ g§nyU© a³H$‘ ^ê$ eH$Vm. H$moUVm n¶m©¶ A{W©H$ ÑîQ¶m ˶mÀ¶mgmR>r Cn¶w³V Amho ?CH$bnm¶ar 1: (g‘ñ¶m g‘OyZ KoUo)
amOoeH$S>o XmoZ àñVmd AmhoV. ˶mbm XþH$mZXmamZo {Xbobm àñVmd pñdH$mamdm H$s Zmhr ¶mMm {ZíM¶ H$aʶmMr JaOAmho. ¶mH$[aVm ˶mbm XmoÝhr ì¶mOmMo Xa g‘OyZ KoVbo nm{hOoV, EH$ hßVo~§Xr ¶moOZo‘ܶo XþH$mZXmamZo ~Xbbobo Am{U Xþgao~±H$oZo {Xbobo Xa. XmoÝhr§Mr VwbZm H$ê$Z Am{W©H$ÑîQ¶m ’$m¶ÚmMr {ZpíMVr H$aUo.nm¶ar 2: (J{UVr Z‘wݶm§Mo gyÌrH$aU)
nmhm H$s hmßVo~§Xr ¶moOZo‘ܶo g§nyU© a³H$‘ EH$ dfm©V ^amdr bmJob Am{U ˶m‘wio ˶mbm gai ì¶mO AmH$maboOmB©b.
gm¶H$bMr IaoXrMr qH$‘V = < 1800
hßVo~§Xr ¶moOZo‘ܶo gwê$dmVrbm ^amdr bmJUmar a³H$‘ = <600hßVo~§Xr ¶moOZoV ^amdr bmJUmar am{hbobr a³H$‘ =<(1800-600) = < 1200XþH$mZXmamZo AmH$maboë¶m ì¶mOmMm Xa r % X.gm.X.eo. Amho Ago g‘Oy.à˶oH$ hß˶mMr a³H$‘ = <610hßVo~§Xr‘ܶo ^abobr EHy$U a³H$‘ =<610+ <610 = <1200
hßVo~§Xr ¶moOZo‘ ܶo ^ ab ob o ì ¶mO =<1220 - <1200 = <20............(i)
o n{hë¶m ‘{hݶmMr ‘wÔb = <1200Xþgè¶m ‘{hݶmMr ‘wÔb =<‹(1200-610) =< 590
Xþgam hßVm = Xþgar ‘wÔb +AmH$mabobo ì¶mO= < 590 + <20 = < 610
EH$m ‘{hݶmMr EHy$U ‘wÔb < 1200 + <590 = <1790
Amåhmbm ‘m{hV Amho H$s, ì¶mO= P T R100
r1790100
=I ...............(ii)
nm¶ar 3: (g‘ñ¶m gmoS>{dUo)(i) Am{U (ii) dê$Z Amåhmbm {‘iob.
r1790100 = 20
20 12001790
= = 13.14 %r
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nm¶ar 4: (CH$bm§Mo ñnîQ>rH$aU>)hßVo~§Xr ¶moOZo‘ܶo AmH$maboë¶m ì¶mOmMm Xa =13.14 %~±Ho$Zo AmH$maboë¶m ì¶mOmMm Xa =10 %åhUyZ amOoeZo gm¶H$b IaoXr H$aʶmgmR>r ~±Ho$H$Sy>Z ì¶mOmZo n¡go KoVbo nm{hOo. Oo Am{W©H$ ÑîQ¶m ’$m¶ÚmMo Amho. nm¶ar 5: (Z‘wݶm§Mo à‘m{UH$aU>)
¶m CXmhaUm‘ܶo, Z‘wݶmÀ¶m à‘mUrH$aUmbm {VVHo$go ‘hËd {Xbo OmV Zmhr H$maU {H$§‘Vr pñWa ({ZpíMV) AmhoV.VarnU, H$O© KʶmMr à{H«$¶m doJir Amh qH$dm ~°±H$ MH«$$dmT> ì¶mO AmH$mê$ eH$Vo. ˶m‘wio ì¶mO§mÀ¶m XamMr
VwbZm doJir Agy eH$Vo Am{U åhUyZ amOoe Amnbm {ZU©¶ ~Xby eH$Vmo.J{UVr Z‘wݶm§Mo ‘hËd
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