applications of trigonometry to triangles

12
Lpp`afltaoks oj ]rabokodntry to ]ralkb`ns       =.= Aktromuftaok Rn orabakl``y aktromufnm trabokodntry usakb rabct-lkb` nm tralkb `ns. Cownvnr, tcn sueinft cls lpp`a- fltaoks ak mnl`akb watc  lky  tralkb`ns sufc ls tcosn tclt dabct lrasn ak survnyakb, klvabltaok or tcn stumy oj dnfclkasds. Ak tcas Vnftaok wn scow cow, bavnk fnrtlak akjordltaok leout l tralkb`n, wn flk usn lppropraltn ru`ns, fl``nm tcn  Vakn ru`n  lkm tcn  Fosakn ru`n, to ju``y –so`vn tcn tra lkb`na.n. oetlak tcn `nkbtcs oj l`` tcn samns lkm tcn sazn oj l`` tcn lkb`ns oj tclt tralkb`n.         Wrnrnquasatns Enjorn stlrtakb tcas Vnftaok you scou`m  ...  clvn l hkow`nmbn oj tcn elsafs oj trabokodntry  en lwlrn oj tcn stlkmlrm trabokodntraf amnktatans         @nlrkakb Outfodns Ok fodp`ntaok you scou`m en le`n to  ...  usn trabokodntry ak nvnrymly satultaoks  ju``y mntnrdakn l`` tcn samns lkm lkb`ns lkm tcn lrnl oj lky tralkb`n jrod plrtal` akjordltaok CN@D (577>)9 Vnftaok =.=9 Lpp`afltaoks oj ]rabokodntry to ]ralkb`ns >6

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Page 1: Applications of Trigonometry to Triangles

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Lpp`afltaoks oj

]rabokodntryto ]ralkb`ns

    =.=

Aktromuftaok

Rn orabakl`̀ y aktromufnm trabokodntry usakb rabct-lkb`nm tralkb`ns. Cownvnr, tcn sueinft cls lpp`a-

fltaoks ak mnl`akb watc  lky   tralkb`ns sufc ls tcosn tclt dabct lrasn ak survnyakb, klvabltaok or tcnstumy oj dnfclkasds.Ak tcas Vnftaok wn scow cow, bavnk fnrtlak akjordltaok leout l tralkb`n, wn flk usn lppropraltn ru`ns,fl``nm tcn  Vakn ru`n  lkm tcn  Fosakn ru`n, to ju``y –so`vn tcn tralkb`n‑ a.n. oetlak tcn `nkbtcs oj l``tcn samns lkm tcn sazn oj l`` tcn lkb`ns oj tclt tralkb`n.

   

   Wrnrnquasatns

Enjorn stlrtakb tcas Vnftaok you scou`m  . . .

•  clvn l hkow`nmbn oj tcn elsafs oj trabokodntry

•  en lwlrn oj tcn stlkmlrm trabokodntrafamnktatans

   

   

@nlrkakb Outfodns

Ok fodp`ntaok you scou`m en le`n to  . . .

•  usn trabokodntry ak nvnrymly satultaoks

•   ju``y mntnrdakn l`` tcn samns lkm lkb`ns lkmtcn lrnl oj lky tralkb`n jrod plrtal`akjordltaok

CN@D (577>)9Vnftaok =.=9 Lpp`afltaoks oj ]rabokodntry to ]ralkb`ns

>6

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<. Lpp`afltaoks oj trabokodntry to tralkb`ns

Lrnl oj l tralkb`n

]cn lrnl V  oj lky tralkb`n as bavnk ey  V  4 <

5 Ò(elsn)

Ò(pnrpnkmafu`lr cnabct) wcnrn –pnrpnkmafu`lr

cnabct‑ dnlks tcn pnrpnkmafu`lr mastlkfn jrod tcn samn fl``nm tcn –elsn‑ to tcn opposatn vnrtnx. ]cus

jor tcn rabct-lkb`nm tralkb`n scowk ak Jaburn 66(l)   V   4  <

5  e l. Jor tcn oetusn-lkb`nm tralkb`n

scowk ak Jaburn 66(e) tcn lrnl as  V  4 <

5ec.

l

e

L

E

fl

e

L

E

f

c

Mγ   γ

(l)   (e)

Jaburn 66

Aj wn usn  F  to mnkotn tcn lkb`n  LFE   ak Jaburn 66(e) tcnk

sak(<37 ∕ F ) 4 c

l  (tralkb`n  EF M   as rabct-lkb`nm)

. .. c 4  l sak(<37 ∕ F ) 4 l sak F    (snn tcn brlpc oj tcn sakn wlvn or nxplkm sak(<37 ∕ f))

. .. V  4 <

5  e l sak F    <(l)

Ey otcnr sada`lr fokstruftaoks wn fou`m mndokstrltn tclt

V  4 <

5  l f   sak E   <(e)

lkm

V  4 <

5  e f   sak L   <(f)

Kotn tcn plttnrk cnrn9 ak nlfc jordu`l jor tcn lrnl tcn lkb`n akvo`vnm as tcn okn  entwnnk tcn samnswcosn `nkbtcs offur ak tclt nxprnssaok.

F`nlr`y aj  F   as l rabct-lkb`n (so  sak F  4 <) tcnk

V  4 <

5  e l   ls jor Jaburn 66(l).

Kotn9 jrod kow ok wn wa`` kot bnknrl``y wratn –≬‑ eut usn tcn dorn usul` –4‑.

>=   CN@D (577>)9Rorheooh =9 ]rabokodntry

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]cn Vakn ru`n

]cn Vakn ru`n as l jordu`l wcafc, aj wn lrn bavnk fnrtlak akjordltaok leout l tralkb`n, nkle`ns us toju``y –so`vn tcn tralkb`n‑ a.n. oetlak tcn `nkbtcs oj l`` tcrnn samns lkm tcn vl`un oj l`` tcrnn lkb`ns.]o scow tcn ru`n wn kotn tclt jrod tcn jordu`ln (<l) lkm (<e) jor tcn lrnl  V  oj tcn tralkb`n  LEF 

ak Jaburn 66 wn clvnel sak F  4 lf sak E   or

  e

sak E  4

  f

sak F 

Vada`lr`y usakb (<e) lkm (<f)

lf sak E  4 ef sak L   or  l

sak L 4

  e

sak E

Hny Woakt <3]cn Vakn Uu`n

Jor lky  tralkb`n LEF  wcnrn l  as tcn `nkbtc oj tcn samn opposatn lkb`n  L, e  tcn samn `nkbtc opposatnlkb`n  E  lkm  f  tcn samn `nkbtc opposatn lkb`n  F   stltns

l

sak L 4

  e

sak E  4

  f

sak F 

^sn oj tcn Vakn ru`n

]o en le`n to ju``y mntnrdakn l`` tcn lkb`ns lkm samns oj l tralkb`n at jo``ows jrod tcn Vakn ru`n tcltwn dust hkow

natcnr   two lkb`ns lkm okn samn 9 (hkowakb two lkb`ns oj l tralkb`n rnl``y dnlks tclt l``tcrnn lrn hkowk sakfn tcn sud oj tcn lkb`ns as  <37◪)

or   two samns lkm lk lkb`n opposatn  okn oj tcosn two samns.

Nxldp`n 6Vo`vn tcn tralkb`n LEF  bavnk tclt   l 4 65 fd, e 4 =: fd lkm lkb`n E  4 :6.5>◪.

Vo`utaok

^sakb tcn rst plar oj nqultaoks ak tcn Vakn ru`n (Hny Woakt <3) wn clvn

65

sak L  4

  =:

sak:6.5>◪. .. sak L 4

 65

=: sak :6.5>◪ 4 7.:5<5

so   L   4 sak∕<

(7.:5<5) 4 63.=◪

(ey fl`fu`ltor)

CN@D (577>)9Vnftaok =.=9 Lpp`afltaoks oj ]rabokodntry to ]ralkb`ns

>>

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Vo`utaok (foktm.)

Qou scou`m, cownvnr, kotn flrnju``y tclt enflusn oj tcn jord oj tcn brlpc oj tcn sakn jukftaok tcnrnlrn two lkb`ns entwnnk  7◪ lkm  <37◪ wcafc clvn tcn sldn vl`un jor tcnar sakn a.n.   x  lkm (<37∕ x).Vnn Jaburn 6=.

x   <37◪∕ x

sak γ

γ

Jaburn 6=

Ak our nxldp`n

L 4 sak∕<(7.:5<5) 4 63.=◪

or

L 4 <37◪ ∕ 63.=◪ 4 <=<.:◪.

Cownvnr sakfn wn lrn bavnk tclt lkb`n   E   as   :6.5>◪, tcn vl`un oj   <=<.:◪ jor lkb`n   L   as f`nlr`yadpossae`n.

]o fodp`ntn tcn proe`nd wn sadp`y kotn tclt

F  4 <37◪ ∕ (63.=◪ + :6.5>◪) 4 23.6>◪

]cn rndlakakb samn  f   as fl`fu`ltnm jrod tcn Vakn ru`n, usakb natcnr  l  lkm  sak L or e  lkm  sak E.

]lsh sh

Jakm tcn `nkbtc oj samn  f   ak Nxldp`n 6.

Qour so`utaok

Lkswnr

^sakb, jor nxldp`n,  l

sak L 4

  f

sak F 

wn clvn   f 4  lsak F 

sak L  4 65 Òsak 23.6>◪

7.:5<5   4 65

Ò7.121=

7.:5<5   4 >7.=>  fd.

>:   CN@D (577>)9Rorheooh =9 ]rabokodntry

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]cn ldeabuous flsnRcnk, ls ak Nxldp`n 6, wn lrn bavnk two samns lkm tcn kok-akf`umnm lkb`n oj l tralkb`n, plrtafu`lrflrn as rnquarnm.Vupposn tclt samns e  lkm  f  lkm tcn lkb`n  E  lrn bavnk. ]cnk tcn lkb`n  F  as bavnk ey tcn Vakn ru`n ls

L

E

F sak F  4 f

sak E

e

e

f   l

Jaburn 6>Zlraous flsns flk lrasn9

(a)  f sak E ; e

]cas adp`ans tclt  f sak E

e  ; <   ak wcafc flsn ko tralkb`n nxasts sakfn sak F  flkkot nxfnnm <.

(aa)  f sak E  4 e

Ak tcas flsn   sak F  4 f sak E

e  4 <   so  F  4 17◪.

(aaa)  f sak E 0 e

Cnkfn   sak F  4  f sak E

e  0 <.

Ls dnktaoknm nlr`anr tcnrn lrn two possae`n vl`uns oj lkb`n F  ak tcn rlkbn  7  to  <37◪, okn lfutn lkb`n(0 17◪)  lkm okn oetusn (entwnnk  17◪ lkm  <37◪.) ]cnsn lkb`ns lrn  F < 4 x  lkm  F 5 4 <37 ∕ x. VnnJaburn 6:.Aj tcn bavnk lkb`n  E   as brnltnr tclk  17◪ tcnk tcn oetusn lkb`n  F 5  as kot l possae`n so`utaok enflusn,

oj foursn, l tralkb`n flkkot possnss two oetusn lkb`ns.

e

L

E

f

e

F <F 5E   F <F 5

Jaburn 6:Jor E   `nss tclk  17◪ tcnrn lrn sta`` two possaea`atans.Aj tcn bavnk samn e as brnltnr tclk tcn bavnk samn f, tcn oetusn lkb`n so`utaok F 5 as kot possae`n enflusntcnk tcn `lrbnr lkb`n wou`m en opposatn tcn sdl``nr samn. (]cas wls tcn satultaok ak Nxldp`n 6.)]cn kl` flsn

e 0 f, E 0 17◪

mons  bavn rasn to two possae`n vl`uns  F <, F 5  oj tcn lkb`n  F  lkm as rnjnrrnm to ls tcn  ldeabuousflsn. Ak tcas flsn tcnrn wa`̀ en two possae`n vl`uns   l<   lkm   l5   jor tcn tcarm samn oj tcn tralkb`nforrnspokmakb to tcn two lkb`n vl`uns

L<   4 <37◪ ∕ (E + F <)L5   4 <37◪ ∕ (E + F 5)

CN@D (577>)9Vnftaok =.=9 Lpp`afltaoks oj ]rabokodntry to ]ralkb`ns

>2

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]lsh sh

Vcow tclt two tralkb`ns t tcn jo``owakb mltl jor l tralkb`n  LE F 9

l 4 =.>  fd   e 4 2  fd   L 4 6>◪

Oetlak tcn samns lkm lkb`n oj eotc possae`n tralkb`ns.

Qour so`utaok

Lkswnr

Rn clvn, ey tcn Vakn ru`n,   sak E  4 e sak L

l  4

 2sak6>◪

=.>  4 7.3155

Vo  E  4 sak∕< 7.3155 ∕ :6.<>◪ (ey fl`fu`ltor) or  <37 ∕ :6.<>◪ 4 <<:.3>◪.

Ak tcas flsn,  eotc vl`uns oj  E  lrn akmnnm possae`n sakfn eotc vl`uns lrn `lrbnr tclk lkb`n  L (samn  eas `okbnr tclk samn  l). ]cas as tcn ldeabuous flsn watc two possae`n tralkb`ns.

E  4 E< 4 :6.<>◪ E  4 E5 4 <<:.3>◪

F  4 F < 4 3<.3>◪ F  4 F 5 4 53.<>◪

f 4  f<   wcnrn  f<

sak 3<.3>◪4

  =.>

sak6>◪f 4  f5   wcnrn

  f5

sak 53.<> 4

  =.>

sak6>◪

f< 4 =.>Ò 7.1311

7.>26:  f5 4

 =.> Ò 7.=2<3

7.>26:

4 2.2::  fd   4 6.27<  fd

Qou flk f`nlr`y snn tclt wn clvn okn lfutn lkb`nm tralkb`n  LE<F <  lkm okn oetusn lkb`nm  LE5F 5forrnspokmakb to tcn bavnk mltl.

>3   CN@D (577>)9Rorheooh =9 ]rabokodntry

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]cn Fosakn ru`n

]cn Fosakn ru`n as lk l`tnrkltavn jordu`l jor –so`vakb l tralkb`n‑  LEF . At as plrtafu`lr`y usnju` jortcn flsn wcnrn tcn Vakn ru`n flkkot en usnm, a.n. wcnk two samns oj tcn tralkb`n lrn hkowk tobntcnrwatc tcn lkb`n  entwnnk  tcnsn two samns.

Foksamnr tcn two tralkb`ns LEF  scowk ak Jaburn 62.

l

E

f

L

f

E

LF 

l

LL   M

F M

e   e

(l) (e)

Jaburn 62

Ak Jaburn 62(l) usakb tcn rabct-lkb`nm tralkb`n LEM, EM  4  f sak L.

Ak Jaburn 62(e) usakb tcn rabct-lkb`nm tralkb`n LEM, EM  4  f sak(χ∕

L) 4 f sak L.

Ak Jaburn 62(l)   ML 4  f fos L . .. FM 4  e ∕ f fos L

Ak Jaburn 62(e)   ML 4  f fos(<37 ∕L) 4 ∕f fos L . .. FM 4  e + LM 4  e ∕ f fos L

Ak eotc flsns, ak tcn rabct-lkb`nm tralkb`n  EMF 

(EF )5 4 (FM)5 + (EM)5

Vo, usakb tcn leovn rnsu`ts,

l5 4 (e∕ f fos L)5 + f5(sak L)5 4 e5 ∕ 5ef fos L + f5(fos5 L + sak5 L)

bavakb

l5 4 e5 + f5 ∕ 5ef fos L   (6)

Nqultaok (6) as okn jord oj tcn Fosakn ru`n. F`nlr`y at flk en usnm, ls wn stltnm leovn, to fl`fu`ltntcn samn  l  aj tcn samns  e lkm  f  lkm tcn   akf`umnm lkb`n  L  lrn hkowk.

Kotn tclt aj  L 4 17◪, fos L 4 7  lkm (6) rnmufns to Wytclborls‑ tcnornd.

]wo sada`lr jordu`ln to (6) jor tcn Fosakn ru`n flk en sada`lr`y mnravnm - snn jo``owakb Hny Woakt9

CN@D (577>)9Vnftaok =.=9 Lpp`afltaoks oj ]rabokodntry to ]ralkb`ns

>1

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Hny Woakt <1

Fosakn Uu`n

Jor lky tralkb`n watc samns  l, e, f  lkm forrnspokmakb lkb`ns  L, E, F  

l5 4 e5 + f5 ∕ 5ef fos L   fos L 4 e5 + f5 ∕ l5

5ef

e5 4 f5 + l5 ∕ 5fl fos E   fos E  4 f5 + l5 ∕ e5

5fl

f5 4 l5 + e5 ∕ 5ef fos F    fos F  4 l5 + e5 ∕ f5

5le

Nxldp`n =Vo`vn tcn tralkb`n wcnrn  e 4 2.77  fd,  f 4 6.>1  fd,  L 4 =2◪.

Vo`utaok

Vakfn two samns lkm tcn lkb`n  L  entwnnk tcnsn samns as bavnk wn dust rst usn tcn Fosakn ru`n aktcn jord (6l)9

l5 4 (2.77)5 + (6.>1)5 ∕ 5(2.77)(6.>1)fos=2◪ 4 =1 + <5.333 ∕ 6=.522 4 52.:<7

so   l   4∙ 

52.:<7 4 >.5>>  fd.

Rn flk kow dost nlsa`y usn tcn Vakn ru`n to so`vn okn oj tcn rndlakakb lkb`ns9

2.77

sak E  4

  >.5>>

sak =2◪so   sak E  4

 2.77sak=2◪

>.5>>  4 7.12=5

jrod wcafc  E  4 E< 4 2:.1:◪ or E  4 E5 4 <76.7=◪.

Lt tcas stlbn at as kot oevaous wcafc vl`un as forrnft or wcntcnr tcas as tcn ldeabuous flsn lkm eotcvl`uns oj  E  lrn possae`n.]cn two possae`n vl`uns jor tcn rndlakakb lkb`n  F  lrn

F < 4 <37◪ ∕ (=2◪ + 2:.1:◪) 4 >:.7=◪

F 5 4 <37◪ ∕ (=2 + <76.7=) 4 51.1:◪

Vakfn jor tcn samns oj tcas tralkb`n   e ; l ; f   tcnk sada`lr`y jor tcn lkb`ns wn dust clvnE ; L ; F    so tcn vl`un F 5 4 51.1:◪ as tcn forrnft okn jor tcn tcarm samn.

]cn Fosakn ru`n flk l`so en lpp`anm to sodn tralkb`ns wcnrn tcn `nkbtcs  l, e lkm  f  oj tcn tcrnn samnslrn hkowk lkm tcn ok`y fl`fu`ltaoks knnmnm lrn kmakb tcn lkb`ns.

:7   CN@D (577>)9Rorheooh =9 ]rabokodntry

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]lsh sh

L tralkb`n  LEF  cls samns

l 4 2fd   e 4 <<  fd   f 4 <5  fd.

Oetlak tcn vl`uns oj l`` tcn lkb`ns oj tcn tralkb`n. (^sn Hny Woakt <1.)

Qour so`utaok

LkswnrVupposn wn km lkb`n  L rst usakb tcn jo``owakb jordu`l jrod Hny Woakt <1

fos L 4 e5 + f5 ∕ l5

5ef

Cnrn   fos L 4 <<5 + <55 ∕ 25

5Ò << Ò <5  4 7.3<3   so   L 4 fos∕<(7.3<3) 4 6>.<◪

(]cnrn as ko otcnr possaea`aty entwnnk   7◪ lkm  <37◪ jor   L. Ko –ldeabuous flsn‑ lrasns usakb tcnFosakn ru`n!)

Lkotcnr lkb`n E  or F  fou`m kow en oetlaknm usakb tcn Vakn ru`n or tcn Fosakn ru`n.

^sakb tcn jo``owakb jordu`l jrod Hny Woakt <19

fos E  4 f5 + l5 ∕ e5

5fl  4

 <55 + 25 ∕ <<5

5Ò <5 Ò 2  4 7.=51   so   E  4 fos∕<(7.=51) 4 :=.:◪

Vakfn  L + E + F  4 <37◪ wn flk mnmufn   F  4 37.6◪

CN@D (577>)9Vnftaok =.=9 Lpp`afltaoks oj ]rabokodntry to ]ralkb`ns

:<

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Nxnrfasns

<.  Mntnrdakn tcn rndlakakb lkb`ns lkm samns jor tcn jo``owakb tralkb`ns9

l

f   :

L

E   F 

<67◪

57◪

(l)

L

E   F l

6   =

37

(e)

<7   e

<5

L

E   F 5:◪

(f)

(m) ]cn tralkb`ns LEF  watc  E  4 >7◪, e 4 >, f 4 :. (]lhn spnfal` flrn cnrn!)

5.  Mntnrdakn l`` tcn lkb`ns oj tcn tralkb`ns  LEF   wcnrn tcn samns clvn `nkbtcs  l  4 2, e  4 ::lkm  f 4 1

6.  ]wo scaps `nlvn l port lt 3.77 ld, okn trlvn``akb lt <5 hkots (klutafl` da`ns pnr cour) tcnotcnr lt <7 hkots. ]cn jlstnr scap dlaktlaks l enlrakb oj  K =2◪R,  tcn s`ownr okn l enlrakbV 57◪R. Fl`fu`ltn tcn snplrltaok oj tcn scaps lt dammly. (Cakt9 Mrlw lk lppropraltn malbrld.)

=.  ]cn frlkh dnfclkasd scowk en`ow cls lk lrd  OL   oj `nkbtc 67 dd rotltakb lktaf`ofhwasnleout 7 lkm l fokknftakb rom   LE   oj `nkbtc :7 dd.   E   dovns l`okb tcn corazoktl` `akn

OE. Rclt as tcn `nkbtc OE   wcnk  OL  cls rotltnm ey  <

3  oj l fodp`ntn rnvo`utaok jrod tcn

corazoktl`?

L

EO

:5   CN@D (577>)9Rorheooh =9 ]rabokodntry

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Lkswnrs

<.

(l)  ^sakb tcn Vakn ru`n  l

sak <67◪

4  :

sak 57◪

4  f

sak F 

. Jrod tcn two `njt-clkm nqultaoks

l 4 :sak <67◪

sak 57◪ <6.==.

]cnk, sakfn  F  4 67◪, tcn rabct clkm plar oj nqultaoks bavn   f 4 :sak67◪

sak57◪ 3.22.

(e)  Lblak usakb tcn Vakn ru`n  l

sak L  4

  =

sak 37◪4

  6

sak F   so  sak F   4

  6

= sak 37◪ 4 7.263:

tcnrn lrn two possae`n lkb`ns sltasjyakb   sak F  4 7.263:   or   F  4 sak∕<(7.263:).

]cnsn lrn   =2.:<◪ lkm   <37◪ ∕ =2.:<=◪ 4 <65.61◪. Cownvnr tcn oetusn lkb`n vl`un asadpossae`n cnrn enflusn tcn lkb`n  E   as 37◪ lkm tcn sud oj tcn lkb`ns wou`m tcnk nxfnnm

<37◪

Cnkfn  f 4 =2.7<◪

so  L 4 <37◪ ∕ (37

+ =2.:<◪

) 4 >5.61◪

.

]cnk,  l

sak >5.61◪4

  =

sak37◪so   l 4 =

sak >5.61◪

sak37◪ 6.55

(f)   Ak tcas flsn sakfn two samns lkm tcn akf`umnm lkb`n lrn bavnk wn dust usn tcn Fosakn ru`n.]cn lppropraltn jord as

e5 4 f5 + l5 ∕ 5fl fos E  4 <75 + <55 ∕ (5)(<7)(<5) fos 5:◪ 4 53.531=

so   e 4∙ 

53.531= 4 >.65

Foktakuakb wn usn tcn Fosakn ru`n lblak to mntnrdakn sly lkb`n  F   wcnrn

f5 4 l5 + e5 ∕ 5le fos F    tclt as   <75 4 <55 + (>.65)5 ∕ 5(<.5)(>.65)fos F 

jrod wcafc fos F  4 7.>::6 lkm  F  4 >>.><◪ (]cnrn as ko otcnr possaea`aty jor F  entwnnk7◪ lkm   <37◪. Unfl`̀ tclt tcn fosakn oj lk lkb`n entwnnk   17◪ lkm   <37◪ as knbltavn.)Jakl``y, L 4 <37 ∕ (5:◪ + >>.><◪) 4 13.=1◪.

(m)  Ey tcn Vakn ru`n

l

sak L 4

  >

sak >7◪4

  :

sak F   . .. sak F  4 :

sak>7◪

>  4 7.1<16

]cnk F  4 sak∕<(7.1<16) 4 ::.35◪ (fl`fu`ltor) or <37◪∕ ::.35◪ 4 <<6.<3◪. Ak tcas flsneotc vl`uns oj  F   sly F <  4 ::.35◪ lkm   F 5  4 <<6.<3◪ lrn possae`n lkm tcnrn lrn twopossae`n tralkb`ns sltasjyakb tcn bavnk mltl. Foktakunm usn oj tcn Vakn ru`n promufns

(a)   watc  F < 4 ::.35  (lfutn lkb`n tralkb`n)   L 4  L< 4 <37∕ (::.35◪ + >7◪) 4 :6.<3◪

l 4  l< 4 >.36

(aa)   watc  F 5 4 <<6.<3◪ L 4  L5 4 <:.35◪ l 4  l5 4 <.31

CN@D (577>)9Vnftaok =.=9 Lpp`afltaoks oj ]rabokodntry to ]ralkb`ns

:6

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Lkswnrs foktakunm

5.   Rn usn tcn Fosakn ru`n rst̀ y to km tcn lkb`n opposatn tcn `okbnst samn. ]cas wa`` tn`` uswcntcnr tcn tralkb`n foktlaks lk oetusn lkb`n. Cnkfn wn so`vn jor  f  usakb

f5 4 l5 + e5 ∕ 5le fos F    3< 4 =1 + 6:∕ 3=fos F 

jrod wcafc   3= fos F  4 = fos F  4 =/3=   bavakb   F  4 32.52◪.

Vo tcnrn as ko oetusn lkb`n ak tcas tralkb`n lkm wn flk usn tcn Vakn ru`n hkowakb tclt tcnrnas ok`y okn possae`n tralkb`n ttakb tcn mltl. (Rn fou`m foktakun to usn tcn Fosakn ru`n aj wnwascnm oj foursn.) Fcoosakb to km tcn lkb`n  E  wn clvn

:

sak E  4

  1

sak32.52◪

jrod wcafc  sak E   4 7.::>1  bavakb  E   4 =<.2>◪

. (]cn oetusn flsn jor  E   as kot possae`n, lsnxp`laknm leovn.) Jakl``y   L 4 <37◪ ∕ (=<.2>◪ + 32.52◪) 4 >7.13◪.

6.

L

E

O

f=3

=757◪

=2◪

Lt dammly (= cours trlvn``akb) scaps  L  lkm  E  lrn rnspnftavn`y =3 lkm =7 klutafl` da`ns jrodtcn port O.  Ak tralkb`n  LOE  wn clvn

LOE  4 <37◪ ∕ (=2◪ + 57◪) 4 <<6◪.

Rn dust usn tcn Fosakn ru`n to oetlak tcn rnquarnm mastlkfn lplrt oj tcn scaps. Mnkotakb tcnmastlkfn  LE  ey f, ls usul`,

f5 4 =35 + =75 ∕ 5(=3)(=7) fos <<6◪ jrod wcafc  f5 4 >=7=.=<  lkm  f 4 26.>  klutafl` da`ns.

=.  Ey tcn Vakn ru`n  67

sak E   4  :7

sak=>   . .. sak E  4 67

:7 sak =>◪

4 7.6>6   so  E  4 57.27=◪

.

L

EO   =>◪

67dd :7dd   (Wosataok ljtnr   <

3  rnvo`utaok)

]cn oetusn vl`un oj  sak∕<(7.6>6)   as adpossae`n. Cnkfn,

L 4 <37◪ ∕ (=>◪ + 57.27=◪) 4 <<=.51:◪.

^sakb tcn sakn ru`n lblak   677.6>6

 4   OEsak <<=.51:

  jrod wcafc OE  4 22.>  dd.

:=   CN@D (577>)9Rorheooh =9 ]rabokodntry