ALGEBRA II - Mathematics Vision ProjectUses tables, graphs, equations, and written descriptions of...

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The Mathematics Vision Project Scott Hendrickson, Joleigh Honey, Barbara Kuehl, Travis Lemon, Janet Sutorius

© 2018 Mathematics Vision Project Original work © 2013 in partnership with the Utah State Office of Education

This work is licensed under the Creative Commons Attribution CC BY 4.0

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ALGEBRA II

An Integrated Approach

ALGEBRA II // MODULE 1

FUNCTIONS AND THEIR INVERSES

Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org

MODULE 1 - TABLE OF CONTENTS

FUNCTIONS AND THEIR INVERSES

1.1Brutus Bites Back – A Develop Understanding Task Develops the concept of inverse functions in a linear modeling context using tables, graphs, and equations. (F.BF.1, F.BF.4, F.BF.4a) Ready, Set, Go Homework: Functions and Their Inverses 1.1

1.2Flipping Ferraris – A Solidify Understanding Task Extends the concepts of inverse functions in a quadratic modeling context with a focus on domain and range and whether a function is invertible in a given domain. (F.BF.1, F.BF.4, F.BF.4c, F.BF.4d)Ready, Set, Go Homework: Functions and Their Inverses 1.2

1.3Tracking the Tortoise – A Solidify Understanding Task Solidifies the concepts of inverse function in an exponential modeling context and surfaces ideas about logarithms. (F.BF.1, F.BF.4, F.BF.4c, F.BF.4d)Ready, Set, Go Homework: Functions and Their Inverses 1.3

1.4 Pulling a Rabbit Out of a Hat – A Solidify Understanding Task Uses function machines to model functions and their inverses. Focus on finding inverse functions and verifying that two functions are inverses. (F.BF.4, F.BF.4a, F.BF.4b) Ready, Set, Go Homework: Functions and Their Inverses 1.4

1.5 Inverse Universe – A Practice Understanding Task Uses tables, graphs, equations, and written descriptions of functions to match functions and their inverses together and to verify the inverse relationship between two functions. (F.BF.4a, F.BF.4b, F.BF.4c, F.BF.4d)Ready, Set, Go Homework: Functions and Their Inverses 1.5

ALGEBRA II // MODULE 1

FUNCTIONS AND THEIR INVERSES – 1.1

Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org

1.1 Brutus Bites Back

A Develop Understanding Task

RememberCarlosandClarita?Acoupleofyearsago,theystartedearningmoneybytakingcareofpetswhiletheirownersareaway.Duetotheiramazingmathematicalanalysisandtheirlovingcareofthecatsanddogsthattheytakein,CarlosandClaritahavemadetheirbusinessverysuccessful.Tokeepthehungrydogsfed,theymustregularlybuyBrutusBites,thefavoritefoodofallthedogs.

CarlosandClaritahavebeensearchingforanewdogfoodsupplierandhaveidentifiedtwopossibilities.TheCanineCateringCompany,locatedintheirtown,sells7poundsoffoodfor$5.

Carlosthoughtabouthowmuchtheywouldpayforagivenamountoffoodanddrewthisgraph:

1. WritetheequationofthefunctionthatCarlosgraphed.

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ALGEBRA II // MODULE 1

FUNCTIONS AND THEIR INVERSES – 1.1

Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org

Claritathoughtabouthowmuchfoodtheycouldbuyforagivenamountofmoneyanddrewthisgraph:

2.WritetheequationofthefunctionthatClaritagraphed.

3. WriteaquestionthatwouldbemosteasilyansweredbyCarlos’graph.WriteaquestionthatwouldbemosteasilyansweredbyClarita’sgraph.Whatisthedifferencebetweenthetwoquestions?

4. Whatistherelationshipbetweenthetwofunctions?Howdoyouknow?

5.Usefunctionnotationtowritetherelationshipbetweenthefunctions.

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ALGEBRA II // MODULE 1

FUNCTIONS AND THEIR INVERSES – 1.1

Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org

Lookingonline,Carlosfoundacompanythatwillsell8poundsofBrutusBitesfor$6plusaflat$5shippingchargeforeachorder.Thecompanyadvertisesthattheywillsellanyamountoffoodatthesamepriceperpound.

6. ModeltherelationshipbetweenthepriceandtheamountoffoodusingCarlos’approach.

7. ModeltherelationshipbetweenthepriceandtheamountoffoodusingClarita’sapproach.

8. Whatistherelationshipbetweenthesetwofunctions?Howdoyouknow?

9. Usefunctionnotationtowritetherelationshipbetweenthefunctions.

10. WhichcompanyshouldClaritaandCarlosbuytheirBrutusBitesfrom?Why?

3

ALGEBRA II // MODULE 1

FUNCTIONS AND INVERSES – 1.1 1.1

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READYTopic:Inverseoperations

Inverseoperations“undo”eachother.Forinstance,additionandsubtractionareinverseoperations.

Soaremultiplicationanddivision.Inmathematics,itisoftenconvenienttoundoseveraloperations

inordertosolveforavariable.

Solveforxinthefollowingproblems.Thencompletethestatementbyidentifyingthe

operationyouusedto“undo”theequation.

1.24=3x Undomultiplicationby3by_______________________________________________

2. Undodivisionby5by______________________________________________________

3. Undoadd17by_____________________________________________________________

4. Undothesquarerootby___________________________________________________

5. Undothecuberootby_____________________________then___________________

6. Undoraisingxtothe4thpowerby________________________________________

7. Undosquaringby_______________________________then______________________

SET Topic:Linearfunctionsandtheirinverses

CarlosandClaritahaveapetsittingbusiness.Whentheyweretryingtodecidehowmanyeachof

dogsandcatstheycouldfitintotheiryard,theymadeatablebasedonthefollowinginformation.

Catpensrequire6ft2ofspace,whiledogrunsrequire24ft2.CarlosandClaritahaveupto360ft2

availableinthestorageshedforpensandruns,whilestillleavingenoughroomtomovearoundthe

cages.Theymadeatableofallofthecombinationsofcatsanddogstheycouldusetofillthespace.

Theyquicklyrealizedthattheycouldfitin4catsinthesamespaceasonedog.

x5= −2

x +17 = 20

x = 6

x +1( )3 = 2

x4 = 81

x − 9( )2 = 49

READY, SET, GO! Name PeriodDate

4

ALGEBRA II // MODULE 1

FUNCTIONS AND INVERSES – 1.1

1.1

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cats 0 4 8 12 16 20 24 28 32 36 40 44 48 52 56 60

dogs 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

8.Usetheinformationinthetabletowrite5orderedpairsthathavecatsastheinputvalue

anddogsastheoutputvalue.

9.Writeanexplicitequationthatshowshowmanydogstheycanaccommodatebasedonhow

manycatstheyhave.(Thenumberofdogs“d”willbeafunctionofthenumberofcats“c”or

! = #(%).)

10.Usetheinformationinthetabletowrite5orderedpairsthathavedogsastheinputvalue

andcatsastheoutputvalue.

11.Writeanexplicitequationthatshowshowmanycatstheycanaccommodatebasedonhow

manydogstheyhave.(Thenumberofcats“c”willbeafunctionofthenumberofdogs“d”

or% = '(!).)

Baseyouranswersin#12and#13onthetableatthetopofthepage.

12.Lookbackatproblem8andproblem10.Describehowtheorderedpairsaredifferent.

13.a)Lookbackattheequationyouwroteinproblem9.Describethedomainfor! = #(%).

b)Describethedomainfortheequation% = '(!)thatyouwroteinproblem11.

c)Whatistherelationshipbetweenthem?

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ALGEBRA II // MODULE 1

FUNCTIONS AND INVERSES – 1.1

1.1

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GO Topic:Usingfunctionnotationtoevaluateafunction.

Thefunctions aredefinedbelow.

Calculatetheindicatedfunctionvaluesinthefollowingproblems.Simplifyyouranswers.

14.

15. 16. 17.

18.

19. 20. 20.)(* + ,)

22.

23. 24. 25.

f x( ), g x( ), and h x( )f x( ) = x g x( ) = 5x −12 h x( ) = x2 + 4x − 7

f 10( ) f −2( ) f a( ) f a + b( )

g 10( ) g −2( ) g a( )

h 10( ) h −2( ) h a( ) h a + b( )

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ALGEBRA II // MODULE 1

FUNCTIONS AND THEIR INVERSES – 1.2

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1.2 Flipping Ferraris

A Solidify Understanding Task

Whenpeoplefirstlearntodrive,theyareoftentoldthatthefastertheyaredriving,thelongeritwilltaketostop.So,whenyou’redrivingonthefreeway,youshouldleavemorespacebetweenyourcarandthecarinfrontofyouthanwhenyouaredrivingslowlythroughaneighborhood.Haveyoueverwonderedabouttherelationshipbetweenhowfastyouaredrivingandhowfaryoutravelbeforeyoustop,afterhittingthebrakes?

1. Thinkaboutitforaminute.Whatfactorsdoyouthinkmightmakeadifferenceinhowfaracartravelsafterhittingthebrakes?

Therehasactuallybeenquiteabitofexperimentalworkdone(mostlybypolicedepartmentsandinsurancecompanies)tobeabletomathematicallymodeltherelationshipbetweenthespeedofacarandthebrakingdistance(howfarthecargoesuntilitstopsafterthedriverhitsthebrakes).

2. Imagineyourdreamcar.MaybeitisaFerrari550Maranello,asuper-fastItaliancar.Experimentshaveshownthatonsmooth,dryroads,therelationshipbetweenthebrakingdistance(d)andspeed(s)isgivenby!(#) = 0.03#) .Speedisgiveninmiles/hourandthedistanceisinfeet.a) Howmanyfeetshouldyouleavebetweenyouandthecarinfrontofyouifyouare

drivingtheFerrariat55mi/hr?

b) Whatdistanceshouldyoukeepbetweenyouandthecarinfrontofyouifyouaredrivingat100mi/hr?

c) Ifanaveragecarisabout16feetlong,abouthowmanycarlengthsshouldyouhavebetweenyouandthatcarinfrontofyouifyouaredriving100mi/hr?

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ALGEBRA II // MODULE 1

FUNCTIONS AND THEIR INVERSES – 1.2

Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org

d) Itmakessensetoalotofpeoplethatifthecarismovingatsomespeedandthengoestwiceasfast,thebrakingdistancewillbetwiceasfar.Isthattrue?Explainwhyorwhynot.

3.Graphtherelationshipbetweenbrakingdistanced(s),andspeed(s),below.

4.AccordingtotheFerrariCompany,themaximumspeedofthecarisabout217mph.UsethistodescribeallthemathematicalfeaturesoftherelationshipbetweenbrakingdistanceandspeedfortheFerrarimodeledby!(#) = 0.03#) .

5.WhatifthedriveroftheFerrari550wascruisingalongandsuddenlyhitthebrakestostopbecauseshesawacatintheroad?Sheskiddedtoastop,andfortunately,missedthecat.Whenshegotoutofthecarshemeasuredtheskidmarksleftbythecarsothatsheknewthatherbrakingdistancewas31ft.

a)Howfastwasshegoingwhenshehitthebrakes?

b)Ifshedidn’tseethecatuntilshewas15feetaway,whatisthefastestspeedshecouldbetravelingbeforeshehitthebrakesifshewantstoavoidhittingthecat?

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ALGEBRA II // MODULE 1

FUNCTIONS AND THEIR INVERSES – 1.2

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6.Partofthejobofpoliceofficersistoinvestigatetrafficaccidentstodeterminewhatcausedtheaccidentandwhichdriverwasatfault.Theymeasurethebrakingdistanceusingskidmarksandcalculatespeedsusingthemathematicalrelationshipsjustlikewehavehere,althoughtheyoftenusedifferentformulastoaccountforvariousfactorssuchasroadconditions.Let’sgobacktotheFerrarionasmooth,dryroadsinceweknowtherelationship.Createatablethatshowsthespeedthecarwastravelingbaseduponthebrakingdistance.

7.Writeanequationofthefunctions(d)thatgivesthespeedthecarwastravelingforagivenbrakingdistance.

8.Graphthefunctions(d)anddescribeitsfeatures.

9.Whatdoyounoticeaboutthegraphofs(d)comparedtothegraphofd(s)?Whatistherelationshipbetweenthefunctionsd(s)ands(d)?

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ALGEBRA II // MODULE 1

FUNCTIONS AND THEIR INVERSES – 1.2

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10.Considerthefunction!(#) = 0.03#)overthedomainofallrealnumbers,notjustthedomainofthisproblemsituation.Howdoesthegraphchangefromthegraphofd(s)inquestion#3?

11.Howdoeschangingthedomainofd(s)changethegraphoftheinverseofd(s)?

12.Istheinverseofd(s)afunction?Justifyyouranswer.

10

ALGEBRA II // MODULE 1

FUNCTIONS AND INVERSES – 1.2

1.2

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READY Topic:SolvingforavariableSolveforx.

1. 17 = 5% + 2

2.2%( − 5 = 3%( − 12% +31

3.11 = √2% + 1

4.√%( + % − 2 = 25.−4 = √5% + 1- 6.√352- = √7%( + 9-

7.30 = 243 8.50 = 11(2 9.40 = 1

3(

SET Topic:Exploringinversefunctions

10.Studentsweregivenasetofdatatograph.Aftertheyhadcompletedtheirgraphs,each

studentsharedhisgraphwithhisshoulderpartner.WhenEthanandEmmasaweach

other’sgraphs,theyexclaimedtogether,“Yourgraphiswrong!”Neithergraphiswrong.

ExplainwhatEthanandEmmahavedonewiththeirdata.

Ethan’sgraph

Emma’sgraph

READY, SET, GO! Name PeriodDate

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ALGEBRA II // MODULE 1

FUNCTIONS AND INVERSES – 1.2

1.2

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11.DescribeasequenceoftransformationsthatwouldtakeEthan’sgraphontoEmma’s.

12.Abaseballishitupwardfromaheightof3feetwith

aninitialvelocityof80feetpersecond(about55mph).Thegraphshowstheheightoftheballatanygivensecondduringitsflight.Usethegraphtoanswerthequestionsbelow.

a. Approximatethetimethattheballisatitsmaximumheight.

b. Approximatethetimethattheballhitstheground.

c. Atwhattimeistheball67feetabovetheground?

d. Makeanewgraphthatshowsthetimewhentheballisatthegivenheights.

e. Isyournewgraphafunction?Explain.

6

7

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3

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ALGEBRA II // MODULE 1

FUNCTIONS AND INVERSES – 1.2

1.2

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GO Topic:Usingfunctionnotationtoevaluateafunction

Thefunctions aredefinedbelow.

Calculatetheindicatedfunctionvalues.Simplifyyouranswers.

13.4(7) 14.4(−9) 15.4(7) 16.4(7 − 8)

17.9(7) 18.9(−9) 19.9(7) 20.9(7 − 8)

21.ℎ(7) 22.ℎ(−9) 23.ℎ(7) 24.ℎ(7 − 8)

Noticethatthenotationf(g(x))isindicatingthatyoureplacexinf(x)withg(x).

Simplifythefollowing.

25.f(g(x)) 26.f(h(x)) 27.g(f(x))

f x( ), g x( ), and h x( )

f x( ) = 3x g x( ) = 10x + 4 h x( ) = x2 − x

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ALGEBRA II // MODULE 1

FUNCTIONS AND THEIR INVERSES – 1.3

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1.3 Tracking the Tortoise

A Solidify Understanding Task

Youmayrememberataskfromlastyearaboutthefamousracebetweenthetortoiseandthehare.Inthechildren’sstoryofthetortoiseandthehare,theharemocksthetortoiseforbeingslow.Thetortoisereplies,“Slowandsteadywinstherace.”Theharesays,“We’lljustseeaboutthat,”andchallengesthetortoisetoarace.

Inthetask,wemodeledthedistancefromthestartinglinethatboththetortoiseandtheharetravelledduringtherace.Todaywewillconsideronlythejourneyofthetortoiseintherace.

Becausethehareissoconfidentthathecanbeatthetortoise,hegivesthetortoisea1meterheadstart.Thedistancefromthestartinglineofthetortoiseincludingtheheadstartisgivenbythefunction:

!(#) = 2( (dinmetersandtinseconds)

Thetortoisefamilydecidestowatchtheracefromthesidelinessothattheycanseetheirdarlingtortoisesister,Shellie,provethevalueofpersistence.

1. Howfarawayfromthestartinglinemustthefamilybe,tobelocatedintherightplaceforShellietorunby5secondsafterthebeginningoftherace?After10seconds?

2. Describethegraphofd(t),Shellie’sdistanceattimet.Whataretheimportantfeaturesofd(t)?

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ALGEBRA II // MODULE 1

FUNCTIONS AND THEIR INVERSES – 1.3

Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org

3. Ifthetortoisefamilyplanstowatchtheraceat64metersawayfromShellie’sstartingpoint,howlongwilltheyhavetowaittoseeShellierunpast?

4. HowlongmusttheywaittoseeShellierunbyiftheystand1024metersawayfromher

startingpoint?

5. DrawagraphthatshowshowlongthetortoisefamilywillwaittoseeShellierunbyatagivenlocationfromherstartingpoint.

6. HowlongmustthefamilywaittoseeShellierunbyiftheystand220metersawayfrom

herstartingpoint?

7. Whatistherelationshipbetweend(t)andthegraphthatyouhavejustdrawn?Howdidyouused(t)todrawthegraphin#5?

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ALGEBRA II // MODULE 1

FUNCTIONS AND THEIR INVERSES – 1.3

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8. Considerthefunction)(*) = 2+ .A) Whatarethedomainandrangeof)(*)?Is)(*)invertible?

B) Graph)(*)and)01(*)onthegridbelow.

C) Whatarethedomainandrangeof)01(*)?

9. If)(3) = 8,whatis)01(8)?Howdoyouknow?

10. If) 5167 = 1.414,whatis)01(1.414)?Howdoyouknow?

11. If)(;) = <whatis)01(<)?Willyouranswerchangeiff(x)isadifferentfunction?Explain.

16

ALGEBRA II // MODULE 1

FUNCTIONS AND INVERSES – 1.3

1.3

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READY Topic:Solvingexponentialequations.Solveforthevalueofx.

1. 5"#$ = 5&"'( 2. 7("'& = 7'&"#* 3. 4(" = 2&"'*

4. 3."'/ = 9&"'( 5. 8"#$ = 2&"#( 6. 3"#$ = $

*$

SET Topic:ExploringtheinverseofanexponentialfunctionInthefairytaleJackandtheBeanstalk,Jackplantsamagicbeanbeforehegoestobed.InthemorningJackdiscoversagiantbeanstalkthathasgrownsolarge,itdisappearsintotheclouds.Buthereisthepartofthestoryyouneverheard.Writtenonthebagcontainingthemagicbeanswasthisnote.Plant a magic bean in rich soil just as the sun is setting. Do not look at the plant site for 10 hours. (This is part of the magic.) After the bean has been in the ground for 1 hour, the growth of the sprout can be modeled by the function 2(4) = 36. (b in feet and t in hours) Jackwasagoodmathstudent,soalthoughheneverlookedathisbeanstalkduringthenight,heusedthefunctiontocalculatehowtallitshouldbeasitgrew.Thetableontherightshowsthecalculationshemadeeveryhalfhour.Hence,Jackwasnotsurprisedwhen,inthemorning,hesawthatthetopofthebeanstalkhaddisappearedintotheclouds.

Time(hours) Height(feet)1 31.5 5.22 92.5 15.63 273.5 46.84 814.5 140.35 2435.5 420.96 7296.5 1,262.77 2,1877.5 3,7888 6,5618.5 11,3649 19,6839.5 34,09210 59,049

READY, SET, GO! Name PeriodDate

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ALGEBRA II // MODULE 1

FUNCTIONS AND INVERSES – 1.3

1.3

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7.DemonstratehowJackusedthemodel2(4) = 36 tocalculatehowhighthebeanstalkwouldbe

after6hourshadpassed.(Youmayusethetablebutwritedownwhereyouwouldputthenumbersinthefunctionifyoudidn’thavethetable.)

8.Duringthatsamenight,aneighborwasplayingwithhisdrone.Itwasprogrammedtohoverat

243ft.Howmanyhourshadthebeanstalkbeengrowingwhenitwasashighasthedrone?9.Didyouusethetableinthesamewaytoanswer#8asyoudidtoanswer#7? Explain.10.WhileJackwasmakinghistable,hewaswonderinghowtallthebeanstalkwouldbeafterthe

magical10hourshadpassed.Hequicklytypedthefunctionintohiscalculatortofindout.WritetheequationJackwouldhavetypedintohiscalculator.

11.Commercialjetsflybetween30,000ft.and36,000ft.Abouthowmanyhoursofgrowingcould

passbeforethebeanstalkmightinterferewithcommercialaircraft?Explainhowyougotyouranswer.

12.Usethetabletofind9(7)and9'$(11,364).13.Usethetabletofind9(9)and9'$(9).13.Explainwhyit’spossibletoanswersomeofthequestionsabouttheheightofthebeanstalkby

justpluggingthenumbersintothefunctionruleandwhysometimesyoucanonlyusethetable.

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ALGEBRA II // MODULE 1

FUNCTIONS AND INVERSES – 1.3

1.3

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GO Topic:EvaluatingfunctionsThefunctions aredefinedbelow.

f(x) = −2x g(x) = 2x + 5 h(x) = x& + 3x − 10

Calculatetheindicatedfunctionvalues.Simplifyyouranswers.

14.f(a)

15.f(b&) 16.f(a + b) 17.fFG(H)I

18.g(a)

19.g(b&) 20.g

(a + b) 21.hFf(H)I

22.h(a)

23.h(b&) 24.h

(a + b) 25.hFG(H)I

f x( ), g x( ), and h x( )

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ALGEBRA II // MODULE 1

FUNCTIONS AND THEIR INVERSES – 1.4

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1.4 Pulling a Rabbit Out of the Hat A Solidify Understanding Task Ihaveamagictrickforyou:

• Pickanumber,anynumber.• Add6• Multiplytheresultby2• Subtract12• Divideby2• Theansweristhenumberyoustartedwith!

Peopleareoftenmystifiedbysuchtricksbutthoseofuswhohavestudiedinverseoperationsandinversefunctionscaneasilyfigureouthowtheyworkandevencreateourownnumbertricks.Let’sgetstartedbyfiguringouthowinversefunctionsworktogether.

Foreachofthefollowingfunctionmachines,decidewhatfunctioncanbeusedtomaketheoutputthesameastheinputnumber.Describetheoperationinwordsandthenwriteitsymbolically.

Here’sanexample:

Input Output

!(#) = # + 8 !)*(#) = # − 8

# = 7 7 7 + 8 = 15

Inwords:Subtract8fromtheresult

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ALGEBRA II // MODULE 1

FUNCTIONS AND THEIR INVERSES – 1.4

Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org

1.

2.

Inwords:

Input Output

!(#) = 3# !)*(#) =

# = 7 7 3 ∙ 7 = 21

Input Output

!(#) = #/ !)*(#) =

# = 7 7 7/ = 49

Inwords:

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ALGEBRA II // MODULE 1

FUNCTIONS AND THEIR INVERSES – 1.4

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3.

4.

5.

Inwords:

Input Output

!(#) = 23 !)*(#) =

# = 7 7 24 = 128

Input Output

!(#) = 2# − 5 !)*(#) =

# = 7 7 2 ∙ 7 − 5 = 9

Input Output

!(#) = # + 53 !)*(#) =

# = 7 7 7 + 53 = 4

Inwords:

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ALGEBRA II // MODULE 1

FUNCTIONS AND THEIR INVERSES – 1.4

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6.

7.

Input Output

!(#) = (# − 3)/ !)*(#) =

# = 7 7 (7 − 3)/ = 16

Input Output

!(#) = 4 − √# !)*(#) =

# = 7 7 4 − √7

Inwords:

Inwords:

Inwords:

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ALGEBRA II // MODULE 1

FUNCTIONS AND THEIR INVERSES – 1.4

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8.

9.Eachoftheseproblemsbeganwithx=7.Whatis thedifferencebetweenthe#usedin!(#)andthe#used in!)*(#)?

10.In#6,couldanyvalueof#beusedin!(#)andstillgivethesameoutputfrom!)*(#)?Explain.Whatabout#7?

11.Basedonyourworkinthistaskandtheothertasksinthismodulewhatrelationshipsdoyouseebetweenfunctionsandtheirinverses?

Inwords:

Input Output

!(#) = 23 − 10 !)*(#) =

# = 7 7 24 − 10 = 118

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ALGEBRA II // MODULE 1

FUNCTIONS AND INVERSES – 1.4

1.4

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READY Topic:PropertiesofexponentsUsetheproductruleorthequotientruletosimplify.Leaveallanswersinexponentialformwithonlypositiveexponents.

1. 3" ∙ 3$

2.7& ∙ 7" 3.10)* ∙ 10+ 4. 5- ∙ 5)"

5. .&.$

6. 2" ∙ 2)0 ∙ 2 7. 1221)$ 8. +3

+4

9.-5-

10.0305 11.

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69

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SET Topic:Inversefunction13. Giventhefunctions:(<) = √< − 1BCDE(<) = <& + 7:

a.Calculate:(16)BCDE(3).

b.Write:(16)asanorderedpair.

c.WriteE(3)asanorderedpair.

d.Whatdoyourorderedpairsfor:(16)andE(3)imply?

e.Find:(25).

f.Basedonyouranswerfor:(25),predictE(4).

g.FindE(4). Didyouranswermatchyourprediction?

h.Are:(<)BCDE(<)inversefunctions? Justifyyouranswer.

READY, SET, GO! Name PeriodDate

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ALGEBRA II // MODULE 1

FUNCTIONS AND INVERSES – 1.4

1.4

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Matchthefunctioninthefirstcolumnwithitsinverseinthesecondcolumn.

:(<) :)2(<)16.:(<) = 3< + 5

a.:)2(<) = KLE$<

17.:(<) = <$ b.:)2(<) = √<9

18.:(<) = √< − 33 c.:)2(<) = M)$0

19.:(<) = <0 d.:)2(<) = M0 − 5

20.:(<) = 5M e.:)2(<) = KLE0<

21.:(<) = 3(< + 5) f.:)2(<) = <$ + 3

22.:(<) = 3M g.:)2(<) = √<3

GO Topic:Compositefunctionsandinverses

CalculateNOP(Q)RSTUPON(Q)Rforeachpairoffunctions.(Note:thenotation(: ∘ E)(<)BCD(E ∘ :)(<)meansthesamethingas:OE(<)RBCDEO:(<)R,respectively.)

23.:(<) = 2< + 5E(<) = M)$

&

24.:(<) = (< + 2)0E(<) = √<9 − 2

25.:(<) = 0* < + 6E(<) =

*(M)")0

26.:(<) = )0M + 2E(<) =

)0M)&

26

ALGEBRA II // MODULE 1

FUNCTIONS AND INVERSES – 1.4

1.4

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Matchthepairsoffunctionsabove(23-26)withtheirgraphs.Labelf(x)andg(x).

a. b.

c. d.

27.Graphtheliney=xoneachofthegraphsabove.Whatdoyounotice?

28.Doyouthinkyourobservationsaboutthegraphsin#27hasanythingtodowiththe

answersyougotwhenyoufound:OE(<)RBCDEO:(<)R?Explain.

29.Lookatgraphb.Shadethe2trianglesmadebythey-axis,x-axis,andeachline.Whatis

interestingaboutthesetwotriangles?

30.Shadethe2trianglesingraphd.Aretheyinterestinginthesameway?Explain.

27

ALGEBRA II // MODULE 1

FUNCTIONS AND THEIR INVERSES – 1.5

Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org

1.5 Inverse Universe A Practice Understanding Task Youandyourpartnerhaveeachbeengivenadifferent

setofcards.Theinstructionsare:

1. Selectacardandshowittoyourpartner.2. Worktogethertofindacardinyourpartner’sset

ofcardsthatrepresentstheinverseofthefunctionrepresentedonyourcard.

3. Recordthecardsyouselectedandthereasonthatyouknowthattheyareinversesinthespacebelow.

4. Repeattheprocessuntilallofthecardsarepairedup.

*Forthistaskonly,assumethatalltablesrepresentpointsonacontinuousfunction.

Pair1: _____________________ Justificationofinverserelationship:____________________________________

Pair2: _____________________ Justificationofinverserelationship:____________________________________

Pair3: _____________________ Justificationofinverserelationship:____________________________________

Pair4: _____________________ Justificationofinverserelationship:____________________________________

Pair5: _____________________ Justificationofinverserelationship:____________________________________

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http

s://f

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28

ALGEBRA II // MODULE 1

FUNCTIONS AND THEIR INVERSES – 1.5

Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org

Pair6: _____________________ Justificationofinverserelationship:____________________________________

Pair6: _____________________ Justificationofinverserelationship:____________________________________

Pair7: _____________________ Justificationofinverserelationship:____________________________________

Pair8: _____________________ Justificationofinverserelationship:____________________________________

Pair9: _____________________ Justificationofinverserelationship:____________________________________

Pair10:_____________________ Justificationofinverserelationship:____________________________________

29

A1

𝑓(𝑥) = {−2𝑥 − 2, −5 < 𝑥 < 0−2, 𝑥 ≥ 0

A3 Each input value, 𝑥, is squared and then 3 is added to the result. The domain of the function is [0,∞)

A5

x y -2 -3 2 3 0 0 6 5 4 4

−43

-2

A2 The function increases at a constant rate of 𝑎

𝑏 and the y-intercept is (0, c).

A4

A6

𝑦 = 3𝑥

A8

A7

x y -5 -125 -3 -27 -1 -1 1 1 3 27 5 125

A9

A10 Yasmin started a savings account with $5. At the end of each week, she added 3. This function models the amount of money in the account for a given week.

B1

𝑦 = log3 𝑥

B2

𝑓(𝑥) = { 23 𝑥, −3 < 𝑥 < 3

2𝑥 − 4, 𝑥 ≥ 3

B4

x y -216 -6 -64 -4 -8 -2 0 0 8 2

64 4 216 6

B3 The x-intercept is (c, 0) and the slope of the line is 𝑏

𝑎.

B6

x y 3 0 4 1 7 2

12 3 19 4 28 5 39 6

B5

B7

B8

𝒙 y -2 -3 -1 -2 0 1 1 6 2 13

B9

B10 The function is continuous and grows by an equal factor of 5 over equal intervals. The y-intercept is (0,1).

ALGEBRA II // MODULE 1

FUNCTIONS AND INVERSES – 1.5

1.5

Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org

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READY Topic:PropertiesofexponentsUsepropertiesofexponentstosimplifythefollowing.Writeyouranswersinexponentialformwithpositiveexponents.1.√"#$ ∙ √"&$

2.√"' ∙ √"( ∙ √")

3.√*) ∙ √*#' ∙ √+&,

4.√32, ∙ √9 ∙ √27'

5.√8( ∙ √16' ∙ √2)

6.(5#)&

7.(7#)78

8.(379)7:

9.;:<(

:=>&

SET Topic:RepresentationsofinversefunctionsWritetheinverseofthegivenfunctioninthesameformatasthegivenfunction.Functionf(x)

Inverse?78(")

10.x f(x)

-8 0

-4 3

0 6

4 9

8 12

10.

READY, SET, GO! Name PeriodDate

30

ALGEBRA II // MODULE 1

FUNCTIONS AND INVERSES – 1.5

1.5

Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org

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11. 12.

12.?(") = −2" + 4

13.?(") = EFG&"

14.

15.x ?(")

0 0

1 1

2 4

3 9

4 16

15.

31

ALGEBRA II // MODULE 1

FUNCTIONS AND INVERSES – 1.5

1.5

Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org

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GO Topic:CompositefunctionsCalculateHIJ(K)LMNOJIH(K)Lforeachpairoffunctions.

(Note:thenotation(? ∘ G)(")*QR(G ∘ ?)(")meanthesamething,respectively.)

16.?(") = 3" + 7; G(") = −4" − 11

17.?(") = −4" + 60; G(") = − 89" + 15

18.?(") = 10" − 5; G(") = #: " + 3

19.?(") = −#& " + 4; G(") = − &

# " + 6

20.Lookbackatyourcalculationsfor?IG(")L*QRGI?(")L.Twoofthepairsofequationsare

inversesofeachother.Whichonesdoyouthinktheyare?

Why?

32

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