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SL1.AlgFuncCh5Transforms.1718.notebook 1 November 12, 2017 11/9 5A Graphs of functions Much of mathematics is based on just a few functions. There are general principals that apply to all functions. By understanding them, you can interpret, graph, and analyze an infinite number of common situations. Some of the primary function families are given below. The parent function or (mother or father) is the simplest form, generally centered at the origin with unit coefficients. The family consists of variations of the parent function, obtained by changing various coefficients. Parent Linear y = x Quadratic f(x)=x 2 Square Root Cubic f(x)= x 3 Cube Root Exponential f(x)= b x b >0 Logarithmic f(x) = log b xx >0 Reciprocal Rational It is important to know and recognize the major features of each function family. The general shape of each family should be familiar. Important graphical features of any graph: Domain and Range Axes intercepts Local maxima and minima Zeros or roots Values of x for which the function is undefined Asymptotes Let's review these for the main function families Family Parent Domain* Range* Asymp ? Turn Pts. ? XInt* YInt* Linear y = x No No 1 1 Quadratic f(x) = x 2 y≥0 No Yes 0, 1, 2 1 Square Root x≥0 y≥0 No No 1 1* Cubic f(x)= x 3 No Yes 1, 2, 3 1 Cube Root No No 1 1* Exponential f(x)= b x b >0 y>0 Yes No 0* 1 Logarithmic f(x) = log b xx >0 x>0 Yes No 1 0* Reciprocal x≠0 y≠0 Yes No 0* 0* Rational H & V.! No 0, 1 0, 1 *The domain, range and number of intercepts is for the parent function. A member of the family may have different values, depending on how it is shifted or stretched. 5A: #1,3,4,5 (Graphing Functions) Objectives 1. Recognize and use function families for graphing 4H: #214 even (Solve growth & decay using logs) Very brief questions QB: #8,9,10,11,16 (QB Growth & Decay) Exponent & Log Test today Intro to what's next 5A: #1,3,4,5 (Graphing Functions)

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  • SL1.AlgFuncCh5Transforms.1718.notebook

    1

    November12,2017

    11/95AGraphsoffunctions

    Muchofmathematicsisbasedonjustafewfunctions.Therearegeneralprincipalsthatapplytoallfunctions.Byunderstandingthem,youcaninterpret,graph,andanalyzeaninfinitenumberofcommonsituations.

    Someoftheprimaryfunctionfamiliesaregivenbelow.Theparentfunctionor(motherorfather)isthesimplestform,generallycenteredattheoriginwithunitcoefficients.Thefamilyconsistsofvariationsoftheparentfunction,obtainedbychangingvariouscoefficients.

    Parent

    Linear y=x

    Quadratic f(x)=x2

    SquareRoot

    Cubic f(x)=x3

    CubeRoot

    Exponential f(x)=bxb>0

    Logarithmic f(x)=logbxx>0

    Reciprocal

    Rational

    Itisimportanttoknowandrecognizethemajorfeaturesofeachfunctionfamily.Thegeneralshapeofeachfamilyshouldbefamiliar.

    Importantgraphicalfeaturesofanygraph: DomainandRange Axesintercepts Localmaximaandminima Zerosorroots Valuesofxforwhichthefunctionisundefined AsymptotesLet'sreviewtheseforthemainfunctionfamilies

    Family Parent Domain* Range* Asymp?

    Turn

    Pts.?

    XInt* YInt*

    Linear y=x No No 1 1

    Quadratic f(x)=x2 y0 No Yes 0,1,2 1

    SquareRoot x0 y0 No No 1 1*

    Cubic f(x)=x3 No Yes 1,2,3 1

    CubeRoot No No 1 1*

    Exponential f(x)=bxb>0 y>0 Yes No 0* 1

    Logarithmic f(x)=logbxx>0 x>0 Yes No 1 0*

    Reciprocal x0 y0 Yes No 0* 0*

    Rational H&V.! No 0,1 0,1

    *Thedomain,rangeandnumberofinterceptsisfortheparentfunction.Amemberofthefamilymayhavedifferentvalues,dependingonhowitisshiftedorstretched.

    5A:#1,3,4,5(GraphingFunctions)Objectives1. Recognize and use function families for graphing

    4H:#214even(Solvegrowth&decayusinglogs) VerybriefquestionsQB:#8,9,10,11,16(QBGrowth&Decay)

    Exponent&LogTesttoday

    Introtowhat'snext

    5A:#1,3,4,5(GraphingFunctions)

  • SL1.AlgFuncCh5Transforms.1718.notebook

    2

    November12,2017

    11/135BTransformationsIntro

    Startingfromanyfunction,f(x),onecantransformitinseveralways.Graphically,themostcommontransformationsare:

    TranslationsshiftthegraphhorizontallyorverticallybysomeamountStretchesorcompressionsscalethegraphverticallyorhorizontallybysomefactorReflectionsflipthegraphoveragivenlineRotationsrotatethegrapharoundagivenpointbysomeangle.

    Let'sexplorethechangesinthegraphandthechangesintherelatedfunction.

    Beforeyouexploreonyourown,it'sworthreviewingtheideaoffunctioncomposition.Supposewehaveafunction,fthatsquareswhatevercomesintoit.Wewouldwritethatasf(x)=x2sincexrepresents"thethingweputintof".Tohelptalkaboutthis,weusethewordargumenttorepresentthe"expressionthatweputintoafunction".Sointhiscasexistheargumentoff.Ifweputt+5intof,theargumentoffist+5whichiswrittenf(t+5).

    f(x)=(x+3)2

    fx f(x)=x2

    Squaretheinputx+3

    Seeingthisideainreverseisveryhelpfulingraphingcertainfunctions.YouwillpracticefunctioncompositionmoreintheHWforthissection.Payattentiontowhattheresultingfunctionformslookliketheyaresimpletransformationsofacommonmotherfunction!

    Let'slookatsomecompositionsofx2.Thiscanhelpusrecognizeformsthatarisefromtransformationsofit.

    Objectives1. Understand the reasons behind the four basic

    transformations.

    5B:#2,3,4,5(Composition)

    Thisisaveryshortunit.QuizonitwillbeMon,11/205A:#1,3,4,5(GraphingFunctions) Discussall

    5B:#2,3,4,5(Composition)IntroGeogebrasetupsketches

  • SL1.AlgFuncCh5Transforms.1718.notebook

    3

    November12,2017

    11/145CTranslations

    Objectives1. Understand translations in x and y.

    Videolinktolesson:https://youtu.be/HgfzlHR1H5Q

    UsingGeogebraonline,doPartIofthe"ExploringTransformations"activity.YouwillcompletethisaspartofyourHW.

    Quizontransformations:Mon,11/20 (Oneweekfromtoday!)

    5B:#2,3,4,5c&dforall(Composition) Present2d,3d,4d,5d

    5C:#ExploringXformsPartI,#6,7(Investigation)5D:#ExploringXformsPartII,#,7(Investigation)

    You will turn this HW in - it will be graded as a Quiz.

    https://youtu.be/HgfzlHR1H5Q

  • SL1.AlgFuncCh5Transforms.1718.notebook

    4

    November12,2017

    11/145DDilations

    Objectives1. Understand translations in x and y.

    Video:https://youtu.be/5Dm4rW96CO4(Stretches)

    UsingGeogebraonline,doPartIIofthe"ExploringTransformations"activity.YouwillcompletethisaspartofyourHW.

    5C:#ExploringXformsPartI,#6,7(Investigation)5D:#ExploringXformsPartII,#,7(Investigation)

    You will turn this HW in - it will be graded as a Quiz.

    https://youtu.be/5Dm4rW96CO4

  • SL1.AlgFuncCh5Transforms.1718.notebook

    5

    November12,2017

    11/165EReflections

    SummaryofDilations

    SummaryofReflections

    Video:https://www.youtube.com/watch?v=iFYX3MvLt4M(Reflections)

    Objectives1. Understand reflections in x and y.

    QuizonMon,11/20(Tuesdayschedule)

    SummaryofDilations

    SummaryofTranslations

    UsingGeogebraonline,doPartIIIofthe"ExploringTransformations"activity.YouwillcompletethisaspartofyourHW.

    You will turn in the Exploring Transformations work which will be graded as a Quiz.

    5E:#ExploringXformsPartIII,#58(Reflections)5F:#18(MiscTransforms)QB:#17(QBTransformations)

    https://www.youtube.com/watch?v=iFYX3MvLt4M

  • SL1.AlgFuncCh5Transforms.1718.notebook

    6

    November12,2017

    11/165FMiscTransforms

    Thereisnonewinformationforsection5F.Justsomemorepracticelookingatavarietyoftransformationsandcombinationsoftransformations.

    PracticeinpreparationforQuizThursday

    QBProblems ConceptMap

    Forextrapractice,seetheReviewSectionsA,B,andCinthebook.

    Objectives1. Practice miscellaneous combinations of transformations.

    30minQuizontransformationsnexttime....afterdiscussingproblemsandreview.

    You will turn in the Exploring Transformations work which will be graded as a Quiz.

    5E:#ExploringXformsPartIII,#58(Reflections)5F:#18(MiscTransforms)QB:#17(QBTransformations)

  • Attachments

    Reciprocals.ggb

    concept_map.pdf

    Transformations.ggb

    SLA3&4ExpLogPractice.pdf

    SLA5TransformPractice.pdf

    XformGen2.ggb

    geogebra_thumbnail.png

    geogebra_javascript.js

    function ggbOnInit() {}

    geogebra.xml

    SMART Notebook

  • y = f(x)

    y = pf(x)

    y

    x

    A(180, -1)A(180, -1)

    Example: Vertical stretch by a factor of 2

    A (180, -2)0

    y = f(x)

    y = f(qx)

    y

    x

    A(90, 0)A(90, 0)

    Example: Horizontal stretch by a factor of 2

    A (180, 0)0

    y

    x

    Example: Inverse function reflect in y = x

    y = f(x)

    y = f-1(x)

    y = xA(0.5, 3)A(0.5, 3)

    B(-3, -4)B(-3, -4)

    A (3, 0.5)0

    B (-4, -3)0

    y = f(x)

    y

    x

    Example: Horizontal translation 2 units right

    y = f(x-2)

    A (2, 8)0

    B (1, 1)0

    A(0, 8)A(0, 8)

    B(-1, 1)B(-1, 1)

    y = f(x)y

    x

    Example: Vertical translation 3 units up

    y = f(x) + 3

    A (-2, 3)0

    A(-2, 0)A(-2, 0)

    y = f(x)

    y

    x

    Example: Reflection in y-axis

    A (-2, 4)0 A(2, 4)A(2, 4)

    y = f(-x)

    Example: Reflection in x-axisy

    x

    A(2, 4)A(2, 4)

    A (2, -4)0

    y = f(x)

    y = -f(x)

    Transformations

    of graphs y = f(x)Reflection

    Stretch

    Translation

    In y-axis

    y = f(-x)

    In x-axis

    y = -f(x)

    Horizontal

    y = f(x-a)

    Vertical

    y = f(x)+b

    Inverse

    y = f-1(x)

    Vertical

    y = pf(x)

    Horizontal

    y = f(qx)

    p > 0 q > 0

    (

    (ab

    Return to text

    SMART Notebook

    geogebra_thumbnail.png

    geogebra_javascript.js

    function ggbOnInit() {}

    geogebra.xml

    SMART Notebook

  • IB Math Standard Level Year 1 Exponent and Logarithm Practice Alei - Desert Academy

    C:\Users\Bob\Documents\Dropbox\Desert\SL1\1 - Algebra&Functions\Practice\SLA3&4ExpLogPractice.docx on 10/31/15 at 12:13 PM Page 1 of 4

    Exponents & Logs Practice Problems

    1. Solve the equation 9x1 =

    Working:

    Answer: ......................................................................

    (Total 4 marks) 2. Solve the equation 43x1 = 1.5625 102.

    Working:

    Answer: ......................................................................

    (Total 4 marks) 3. If loga 2 = x and loga 5 = y, find in terms of x and y, expressions for

    (a) log2 5; (b) loga 20. Working:

    Answers: (a) .................................................................. (b) ..................................................................

    (Total 4 marks)

    4. Let log10P = x , log10Q = y and log10R = z. Express 2

    10 3logP

    QR

    in terms of x , y and z.

    Working:

    Answer: ....................................................................

    (Total 4 marks)

    .31 2x

  • IB Math Standard Level Year 1 Exponent and Logarithm Practice Alei - Desert Academy

    C:\Users\Bob\Documents\Dropbox\Desert\SL1\1 - Algebra&Functions\Practice\SLA3&4ExpLogPractice.docx on 10/31/15 at 12:13 PM Page 2 of 4

    5. Solve the equation log9 81 + log919

    + log9 3 = log9 x.

    Working:

    Answer: .......................................................................

    (Total 4 marks) 6. Consider the following statements

    A: log10 (10x) > 0. B: 0.5 cos (0.5x) 0.5.

    C: arctan2 2

    x .

    (a) Determine which statements are true for all real numbers x. Write your answers (yes or no) in the table below. Statement (a) Is the statement true for all

    real numbers x? (Yes/No) (b) If not true, example

    A B C

    (b) If a statement is not true for all x, complete the last column by giving an example of one value of x for which the statement is false.

    Working:

    (Total 6 marks) 7. Given that log5 x = y, express each of the following in terms of y.

    (a) log5 x2

    (b) log5

    (c) log25 x Working:

    Answers: (a) .................................................................. (b) .................................................................. (c) ..................................................................

    (Total 6 marks) 8. A population of bacteria is growing at the rate of 2.3% per minute. How long will it take for the size

    of the population to double? Give your answer to the nearest minute. Working:

    Answer: ......................................................................

    (Total 4 marks)

    x1

  • IB Math Standard Level Year 1 Exponent and Logarithm Practice Alei - Desert Academy

    C:\Users\Bob\Documents\Dropbox\Desert\SL1\1 - Algebra&Functions\Practice\SLA3&4ExpLogPractice.docx on 10/31/15 at 12:13 PM Page 3 of 4

    9. Initially a tank contains 10 000 litres of liquid. At the time t = 0 minutes a tap is opened, and liquid then flows out of the tank. The volume of liquid, V litres, which remains in the tank after t minutes is given by

    V = 10 000 (0.933t). (a) Find the value of V after 5 minutes.

    (1) (b) Find how long, to the nearest second, it takes for half of the initial amount of liquid to flow out

    of the tank. (3)

    (c) The tank is regarded as effectively empty when 95% of the liquid has flowed out. Show that it takes almost three-quarters of an hour for this to happen.

    (3) (d) (i) Find the value of 10 000 V when t = 0.001 minutes.

    (ii) Hence or otherwise, estimate the initial flow rate of the liquid. Give your answer in litres per minute, correct to two significant figures.

    (3) (Total 10 marks)

    10. A group of ten leopards is introduced into a game park. After t years the number of leopards, N, is modelled by N = 10 e0.4t. (a) How many leopards are there after 2 years? (b) How long will it take for the number of leopards to reach 100? Give your answers to an

    appropriate degree of accuracy. Give your answers to an appropriate degree of accuracy. Working:

    Answers: (a) .................................................................. (b) ..................................................................

    (Total 4 marks) 11. Each year for the past five years the population of a certain country has increased at a steady rate of

    2.7% per annum. The present population is 15.2 million. (a) What was the population one year ago? (b) What was the population five years ago? Working:

    Answers: (a) .................................................................. (b) ..................................................................

    (Total 4 marks) 12. Michele invested 1500 francs at an annual rate of interest of 5.25 percent,

    compounded annually. (a) Find the value of Micheles investment after 3 years. Give your answer to the nearest franc.

    (3) (b) How many complete years will it take for Micheles initial investment to double in value?

    (3) (c) What should the interest rate be if Micheles initial investment were to double in value in 10

    years? (4)

    (Total 10 marks)

  • IB Math Standard Level Year 1 Exponent and Logarithm Practice Alei - Desert Academy

    C:\Users\Bob\Documents\Dropbox\Desert\SL1\1 - Algebra&Functions\Practice\SLA3&4ExpLogPractice.docx on 10/31/15 at 12:13 PM Page 4 of 4

    13. Solve the equation log27 x = 1 log27 (x 0.4). Working:

    Answer: ......................................................................

    (Total 6 marks) 14. Consider functions of the form y = ekx

    (a) Show that ( )1

    0

    1 1kx ke dx ek

    = . (3)

    (b) Let k = 0.5 (i) Sketch the graph of y = e0.5x, for 1 x 3, indicating the coordinates of the

    y-intercept. (ii) Shade the region enclosed by this graph, the x-axis, y-axis and the line x = 1. (iii) Find the area of this region.

    (5)

    (c) (i) Find dydx

    in terms of k, where y = ekx.

    The point P(1, 0.8) lies on the graph of the function y = ekx. (ii) Find the value of k in this case. (iii) Find the gradient of the tangent to the curve at P.

    (5) (Total 13 marks)

    15. $1000 is invested at 15% per annum interest, compounded monthly. Calculate the minimum number of months required for the value of the investment to exceed $3000. Working:

    Answer: ......................................................................

    (Total 6 marks) 16. The mass m kg of a radio-active substance at time t hours is given by

    m = 4e0.2t. (a) Write down the initial mass. (b) The mass is reduced to 1.5 kg. How long does this take? Working:

    Answers: (a) .................................................................. (b) ..................................................................

    (Total 6 marks)

  • IB Math Standard Level Year 1 Exponent and Logarithm Practice - Markscheme Alei - Desert Academy

    C:\Users\Bob\Documents\Dropbox\Desert\SL1\1 - Algebra&Functions\Practice\SLA3&4ExpLogPractice.docx on 10/31/15 at 12:13 PM Page 1 of 5

    Exponents & Logs Practice Problems - Markscheme

    1. 9x1 =

    32x2 = 32x (M1) (A1) 2x 2 = 2x (A1)

    x = (A1) (C4)

    [4] 2. 43x1 = 1.5625 102

    (3x 1)log10 4 = log10 1.5625 2 (M1)

    3x 1 = 1010

    log 1.5625 2log 4

    (A1)

    3x 1 = 3 (A1)

    x = (A1) (C4)

    [4]

    3. (a) log2 5 = (M1)

    = (A1) (C2)

    (b) loga 20 = loga 4 + loga 5 or loga 2 + loga 10 (M1) = 2 loga 2 + loga 5 = 2x + y (A1) (C2)

    [4]

    4. log10 = 2log10 (M1)

    2log10 = 2(log10P log10(QR3)) (M1)

    = 2(1og10P log10Q 3log10R) (M1) = 2(x y 3z) = 2x 2y 6z or 2(x y 3z) (A1)

    [4] 5. METHOD 1

    log9 81 + log9 + log9 3 = 2 1 + (M1)

    = log9 x (A1)

    x = (M1) x = 27 (A1) (C4)

    METHOD 2 log 81 + log9 + log9 3 = log9 (M2)

    = log9 27 (A1) x = 27 (A1) (C4)

    [4]

    x2

    31

    21

    32

    2log5log

    a

    a

    xy

    2

    3

    QRP

    3QR

    P

    3QR

    P

    91

    21

    23

    23

    9

    91

    3

    918 1

  • IB Math Standard Level Year 1 Exponent and Logarithm Practice - Markscheme Alei - Desert Academy

    C:\Users\Bob\Documents\Dropbox\Desert\SL1\1 - Algebra&Functions\Practice\SLA3&4ExpLogPractice.docx on 10/31/15 at 12:13 PM Page 2 of 5

    6. Statement (a) Is the statement true for all

    real numbers x? (Yes/No) (b) If not true, example

    A No x = l (log10 0.1 = 1) (a) (A3) (C3) B No x = 0 (cos 0 = 1) (b) (A3) (C3) C Yes N/A

    Notes: (a) Award (A1) for each correct answer. (b) Award (A) marks for statements A and B only if NO in column (a). Award (A2) for a correct counter example to statement A, (A1) for a correct counter example to statement B (ignore other incorrect examples). Special Case for statement C: Award (A1) if candidates write NO, and give a valid reason (eg

    arctan 1 = ).

    [6] 7. (a) log5 x2 = 2 log5 x (M1)

    = 2y (A1) (C2)

    (b) log5 = log5 x (M1)

    = y (A1) (C2)

    (c) log25 x = (M1)

    = (A1) (C2) [6]

    8. 1.023t = 2 (M1)

    t = (M1)(A1)

    = 30.48... 30 minutes (nearest minute) (A1) (C4)

    Note: Do not accept 31 minutes. [4]

    9. Note: A reminder that a candidate is penalized only once in this question for not giving answers to 3 sf

    (a) V(5) = 10000 (0.9335) = 7069.8 = 7070 (3 sf) (A1) 1

    (b) We want t when V = 5000 (M1) 5000 = 10000 (0.933)t 0.5 = 0.933t (A1)

    log(0.5) ln(0.5) or log(0.993) ln(0.993)

    t =

    9.9949 = t After 10 minutes 0 seconds, to nearest second (or 600 seconds). (A1) 3

    (c) 0.05 = 0.933t (M1) log(0.5) 43.197 minutes

    log(0.993)t= = (M1)(A1)

    3/4 hour (AG) 3

    45

    x1

    25loglog

    5

    5 x

    y21

    0 2 3.1ln2ln

  • IB Math Standard Level Year 1 Exponent and Logarithm Practice - Markscheme Alei - Desert Academy

    C:\Users\Bob\Documents\Dropbox\Desert\SL1\1 - Algebra&Functions\Practice\SLA3&4ExpLogPractice.docx on 10/31/15 at 12:13 PM Page 3 of 5

    (d) (i) 10000 10000(0.933)0.001 = 0.693 (A1)

    (ii) Initial flow rate = where t = 0, (M1)

    0.6930.001

    dvdt

    = = 693

    = 690 (2 sf) (A1) OR

    dvdt

    = 690 (G2) 3

    [10] 10. (a) At t = 2, N = 10e0.4(2) (M1)

    N = 22.3 (3 sf) Number of leopards = 22 (A1)

    (b) If N = 100, then solve 100 = 100e0.4t

    10 = e04t ln 10 = 0.4t

    t = ~ 5.76 years (3 sf) (A1)

    [4]

    11. (a) = 14.8 million (M1)(A1) (C2)

    (b) 515.2

    (1.027) = 13.3 million (M1)(A1)(C2)

    OR

    414.8

    (1.027)= 13.3 million (M1)(A1)(C2)

    [4] 12. (a) Value = 1500(1.0525)3 (M1)

    = 1748.87 (A1) = 1749 (nearest franc) (A1) 3

    (b) 3000 = 1500(1.0525)t 2 = 1.0525t (M1)

    t = log 2

    log1.0525= 13.546 (A1)

    It takes 14 years. (A1) 3 (c) 3000 = 1500(1 +r)10 or 2(1 +r)10 (M1)

    = 1 + r or log 2 = 10 log (1 + r) (M1)

    r = 1 or r = 1 (A1) r = 0.0718 [or 7.18%] (A1) 4

    [10] 13. log27 (x(x 0.4)) = l (M1)(A1)

    x2 0.4x = 27 (M1) x = 5.4 or x = 5 (G2) x = 5.4 (A1) (C6)

    Note: Award (C5) for giving both roots. [6]

    tV

    dd

    4.010ln

    027.12.15

    10 2

    10 2 102log

    10

  • IB Math Standard Level Year 1 Exponent and Logarithm Practice - Markscheme Alei - Desert Academy

    C:\Users\Bob\Documents\Dropbox\Desert\SL1\1 - Algebra&Functions\Practice\SLA3&4ExpLogPractice.docx on 10/31/15 at 12:13 PM Page 4 of 5

    14. (a) 11

    00

    1kx kxe dx ek

    = (A1)

    = ( )01 ke ek (A1)

    = ( )1 1kek (A1)

    = ( )1 1 kek (AG) 3

    (b) k = 0.5 (i)

    (A2)

    Note: Award (A1) for shape, and (A1) for the point (0,1). (ii) Shading (see graph) (A1)

    (iii) Area =1

    0

    kxe dx for k = 0.5 (M1)

    = (1 e0.5)

    = 0.787 (3 sf) (A1) OR Area = 0.787 (3 sf) (G2) 5

    (c) (i) dydx

    = kekx (A1)

    (ii) x = 1 y = 0.8 0.8 = e k (A1) ln 0.8 = k k = 0.223 (A1)

    (iii) At x = 1 dydx

    = 0.223e0.223 (M1)

    = 0.179 (accept 0.178) (A1) OR dydx

    = 0.178 or 0.179 (G2) 5

    [13]

    15. 15% per annum = % = 1.25% per month (M1)(A1)

    Total value of investment after n months, 1000(1.0125)n > 3000 (M1) => (1.0125)n > 3

    n log (1.0125) > log (3) => n >log3

    log1.0125 (M1)

    Whole number of months required so n = 89 months. (A1) (C6)

    1 0 1 2 3

    1(0,1)

    y

    x

    5.01

    1215

  • IB Math Standard Level Year 1 Exponent and Logarithm Practice - Markscheme Alei - Desert Academy

    C:\Users\Bob\Documents\Dropbox\Desert\SL1\1 - Algebra&Functions\Practice\SLA3&4ExpLogPractice.docx on 10/31/15 at 12:13 PM Page 5 of 5

    Notes: Award (C5) for the answer of 90 months obtained from using n 1 instead of n to set up the equation. Award (C2) for the answer 161 months obtained by using simple interest. Award (C1) for the answer 160 months obtained by using simple interest.

    [6] 16. (a) Initial mass t = 0 (A1)

    mass = 4 (A1) (C2) (b) 1.5 = 4e0.2t (or 0.375 = e0.2t) (M2)

    ln 0.375 = 0.2t (M1) t = 4.90 hours (A1) (C4)

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  • IB Math Standard Level Year 1 Transformation Practice Alei - Desert Academy

    /Users/Shared/Dropbox/Desert/SL1/1 - Algebra&Functions/Practice/SLA5TransformPractice.docx on 11/14/15 at 8:16 PM Page 1 of 5

    Transformations Practice Problems 1. Three of the following diagrams I, II, III, IV represent the graphs of

    (a) y = 3 + cos 2x (b) y = 3 cos (x + 2) (c) y = 2 cos x + 3.

    Identify which diagram represents which graph.

    Working:

    Answers: (a) .................................................................. (b) .................................................................. (c) ..................................................................

    (Total 4 marks)

    x

    12

    12

    32

    y

    2

    1

    1

    2

    x

    12

    12

    32

    y

    3

    2

    1

    3

    y

    x

    4

    2

    12

    12

    32

    x

    12

    12

    32

    5

    4

    3

    2

    1

    y

    I

    III

    II

    IV

  • IB Math Standard Level Year 1 Transformation Practice Alei - Desert Academy

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    2. The diagrams show how the graph of y = x2 is transformed to the graph of y = f (x) in three steps. For each diagram give the equation of the curve.

    Working: Answers:

    (a) .................................................................. (b) .................................................................. (c) ..................................................................

    (Total 4 marks) 3. The diagram shows the graph of y = f (x), with the x-axis as an asymptote.

    (a) On the same axes, draw the graph of y =f (x + 2) 3, indicating the coordinates of the images

    of the points A and B. (b) Write down the equation of the asymptote to the graph of y = f (x + 2) 3.

    Working:

    Answer: (b) ....................................................................

    (Total 4 marks)

    y

    y

    y

    y

    0

    0

    0

    0

    x

    xx

    xy=x2

    4

    1

    1 1

    1

    3

    7

    (a)

    (b) (c)

    A(5, 4)

    B(5, 4)

    y

    x

  • IB Math Standard Level Year 1 Transformation Practice Alei - Desert Academy

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    4. The following diagram shows the graph of y = f (x). It has minimum and maximum points at

    (0, 0) and ( ).

    (a) On the same diagram, draw the graph of y = f(x 1) + 32 .

    (b) What are the coordinates of the minimum and maximum points of y = f(x 1) + 32 ?

    Working:

    Answer: (b) ................................................................

    (Total 4 marks) 5. The sketch shows part of the graph of y = f (x) which passes through the points A(1, 3), B(0, 2),

    C(l, 0), D(2, 1) and E(3, 5).

    A second function is defined by g (x) = 2f (x 1).

    (a) Calculate g (0), g (1), g (2) and g (3). (b) On the same axes, sketch the graph of the function g (x).

    Working:

    Answers: (a) .................................................................. ..................................................................

    (Total 6 marks)

    2

    1,1

    2 1 0 1 2 3

    3.5

    3

    2.5

    2

    1.5

    1

    0.5

    1

    1.5

    0.5

    2

    2.5

    y

    x

    8

    7

    6

    5

    4

    3

    2

    1

    0

    1

    2

    4 3 2 1 1 2 3 4 5

    A

    B

    C

    D

    E

  • IB Math Standard Level Year 1 Transformation Practice Alei - Desert Academy

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    6. (a) The diagram shows part of the graph of the function f (x) = The curve passes through

    the point A (3, 10). The line (CD) is an asymptote.

    Find the value of

    (i) p; (ii) q.

    (b) The graph of f (x) is transformed as shown in the following diagram. The point A is

    transformed to A (3, 10).

    Give a full geometric description of the transformation.

    Working:

    Answers: (a) (i) ........................................................... (ii) ........................................................... (b) .................................................................. ..................................................................

    (Total 6 marks)

    . pxq

    15

    10

    5

    -5

    -10

    -15

    C

    A

    D

    y

    x15105051015

    y

    x

    15

    15

    10

    10

    5

    50

    5

    5

    10

    10

    15

    15

    A

    C

    D

  • IB Math Standard Level Year 1 Transformation Practice Alei - Desert Academy

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    7. The diagram shows parts of the graphs of y = x2 and y = 5 3(x 4)2.

    The graph of y = x2 may be transformed into the graph of y = 5 3(x 4)2 by these transformations.

    A reflection in the line y = 0 followed by a vertical stretch with scale factor k followed by a horizontal translation of p units followed by a vertical translation of q units.

    Write down the value of (a) k; (b) p; (c) q.

    Working:

    Answers: (a) .................................................................. (b) .................................................................. (c) ..................................................................

    (Total 4 marks)

    2

    4

    6

    8

    2 0 2 4 6

    y

    x

    y = x2

    2y x= 5 3( 4)

  • IB Math Standard Level Year 1 Transformation Practice Alei - Desert Academy

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    Transformations Practice Problems - Markscheme 1. (a) I

    (b) III (c) IV

    Note: Award (C4) for 3 correct, (C2) for 2 correct, (C1) for 1 correct. [4]

    2. (a) y = (x 1)2 (A2)(C2) (b) y = 4(x 1)2 (A1) (C1) (c) y = 4(x 1)2 + 3 (A1) (C1)

    Note: Do not penalize if these are correctly expanded. [4]

    3. (a) Correct vertical shift (A1) Coordinates of the images (see diagram) (A1) (A1)

    (b) Asymptote: y = 3 (A1)

    [4] 4. (a)

    (A2)(C2)

    (b) Minimum: (A1) (C1)

    Maximum: (2, 2) (A1) (C1) [4]

    5. (a) g (x) = 2 f (x l) x 0 1 2 3

    x 1 1 0 1 2 f (x 1) 3 2 0 1

    g (0) = 2 f (1) = 6 (A1)(C1) g (1) = 2 f (0) = 4 (A1)(C1) g (2) = 2 f (l) = 0 (A1)(C1) g (3) = 2 f (2) = 2 (A1)(C1)

    A(5, 4)

    B(5, 4)

    y

    x

    A(7, 7)

    B(3, 1)

    2 1 0 1 2 3

    0.5

    1

    1.5

    2

    2.5

    0.5

    1

    1.5

    2

    2.5

    3

    3.5

    y

    x

    (1, )12

    23,1

  • IB Math Standard Level Year 1 Transformation Practice Alei - Desert Academy

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    (b) Graph passing through (0, 6), (1, 4), (2, 0), (3, 2) (A1)

    Correct shape. (A1)

    (C2)

    [6] 6. (a) (i) p = 2 (A2)(C2)

    (ii) 10 = (or equivalent) (M1)

    q = 10 (A1) (C2) (b) Reflection, in x-axis (A1)(A1) (C2)

    [6] 7.

    q = 5 (A1)(C1)

    k = 3, p = 4 (A3)(C3) [4]

    8

    7

    6

    5

    4

    3

    2

    1

    0

    1

    2

    4 3 2 1 1 2 3 4 5

    A

    B

    C

    D

    E

    x

    y

    23q

    2 0 2 4 6

    2

    4

    6

    8y = x

    y = x53( 4)2

    2

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