2019 Specialist Mathematics Written examination 2 · SPECIALIST MATHEMATICS Written examination 2...
Transcript of 2019 Specialist Mathematics Written examination 2 · SPECIALIST MATHEMATICS Written examination 2...
SPECIALIST MATHEMATICSWritten examination 2
Wednesday 5 June 2019 Reading time: 10.00 am to 10.15 am (15 minutes) Writing time: 10.15 am to 12.15 pm (2 hours)
QUESTION AND ANSWER BOOK
Structure of bookSection Number of
questionsNumber of questions
to be answeredNumber of
marks
A 20 20 20B 6 6 60
Total 80
• Studentsarepermittedtobringintotheexaminationroom:pens,pencils,highlighters,erasers,sharpeners,rulers,aprotractor,setsquares,aidsforcurvesketching,oneboundreference,oneapprovedtechnology(calculatororsoftware)and,ifdesired,onescientificcalculator.CalculatormemoryDOESNOTneedtobecleared.Forapprovedcomputer-basedCAS,fullfunctionalitymaybeused.
• StudentsareNOTpermittedtobringintotheexaminationroom:blanksheetsofpaperand/orcorrectionfluid/tape.
Materials supplied• Questionandanswerbookof23pages• Formulasheet• Answersheetformultiple-choicequestions
Instructions• Writeyourstudent numberinthespaceprovidedaboveonthispage.• Checkthatyournameandstudent numberasprintedonyouranswersheetformultiple-choice
questionsarecorrect,andsignyournameinthespaceprovidedtoverifythis.• Unlessotherwiseindicated,thediagramsinthisbookarenotdrawntoscale.• AllwrittenresponsesmustbeinEnglish.
At the end of the examination• Placetheanswersheetformultiple-choicequestionsinsidethefrontcoverofthisbook.• Youmaykeeptheformulasheet.
Students are NOT permitted to bring mobile phones and/or any other unauthorised electronic devices into the examination room.
©VICTORIANCURRICULUMANDASSESSMENTAUTHORITY2019
SUPERVISOR TO ATTACH PROCESSING LABEL HEREVictorian Certificate of Education 2019
STUDENT NUMBER
Letter
SECTION A – continued
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Question 1Thegraphofwhichoneofthefollowingrelationsdoesnothaveaverticalasymptote?
A. y xx
=−3 1
B. y xx
=++
5 21
2
2
C. y xx
=−4
23
D. yx x
=+1
42
E. y xx
=−+12
Question 2Thecurvegivenbyx =3 sec(t)+1andy =2 tan(t)–1canbeexpressedincartesianformas
A. ( ) ( )y x+
−−
=1
41
91
2 2
B. ( ) ( )x y+
−−
=1
31
21
2 2
C. ( ) ( )y x+
−−
=1
91
41
2 2
D. ( ) ( )x y−
++
=1
31
21
2 2
E. ( ) ( )x y−
−+
=1
91
41
2 2
SECTION A – Multiple-choice questions
Instructions for Section AAnswerallquestionsinpencilontheanswersheetprovidedformultiple-choicequestions.Choosetheresponsethatiscorrectforthequestion.Acorrectanswerscores1;anincorrectanswerscores0.Markswillnotbedeductedforincorrectanswers.Nomarkswillbegivenifmorethanoneansweriscompletedforanyquestion.Unlessotherwiseindicated,thediagramsinthisbookarenot drawntoscale.Taketheacceleration due to gravitytohavemagnitudegms–2,whereg=9.8
SECTION A – continuedTURN OVER
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Question 3The maximal domain and range of the function f (x) = a cos–1(bx) + c, where a, b and c are real constants with a > 0, b < 0 and c > 0, are respectivelyA. [0, π] and [–a, a]
B. [0, π] and [–a + c, a + c]
C. −
1 1b b
, and [c, aπ + c]
D. 1 1b b
, −
and [c, aπ + c]
E. 1 1b b
, −
and [–aπ + c, aπ + c]
Question 4Which one of the following statements is false for z1, z2 ∈ C?
A. z zz
z− = ≠12 0,
B. z z z z1 2 1 2+ > +
C. zz
z zz
z1
2
1 2
22 2 0= ≠,
D. z z z z1 2 1 2=
E. zz
zz
z1
2
1
22 0= ≠,
Question 5The circle defined by z a z i+ = +3 , where a ∈ R, has a centre and radius respectively given by
A. a a8
98
38
12, ,−
+
B. a a8
98
9 964
2, ,−
+
C. a a8
98
18
153 7 2, ,−
−
D. −
+a a8
98
9 964
2, ,
E. −
+
a a8
98
38
12, ,
SECTION A – continued
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Question 6P(z)isapolynomialofdegreenwithrealcoefficientswherez ∈ C.Threeoftherootsoftheequation P(z)=0arez=3–2i,z=4andz=–5i.ThesmallestpossiblevalueofnisA. 3B. 4C. 5D. 6E. 7
Question 7Thegradientofthelinethatisperpendicular tothegraphofarelationatanypointP(x,y)ishalfthegradientofthelinejoiningPandthepointQ(–1,1).Therelationsatisfiesthedifferentialequation
A. dydx
yx
=−+1
2 1( )
B. dydx
xy
=++
2 11
( )
C. dydx
xy
=−+
2 11
( )
D. dydx
xy
=+−
12 1( )
E. dydx
xy
=+−
2 11( )
Question 8Thetotalareaenclosedbetweenthex-axisandthegraphof f x x x x( ) = − −3 2 isclosesttoA. –2.015B. –1.008C. 1.008D. 2.015E. 2.824
SECTION A – continuedTURN OVER
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Question 9
Withasuitablesubstitution, 5 11
2x dx−∫ canbeexpressedas
A. 51
2u du∫
B. 15 1
2u du∫
C. 54
9u du∫
D. 15 4
9u du∫
E. 5 5 14
9u du−∫
Question 10Euler’smethod,withastepsizeof0.1,isusedtoapproximatethesolutionofthedifferentialequation1ydydx
x= cos( ),withy =2whenx =0.
Whenx =0.2,thevalueobtainedfor y,correcttofourdecimalplaces,isA. 2.2000B. 2.3089C. 2.3098D. 2.4189E. 2.4199
Question 11Thevectorresoluteof
a i j k= − +2 3 thatisperpendicular to
b i + j k= − is
A. − −( )23
i + j k
B. − −( )23
2i j + 3k
C. 13
8i j + 7k
−( )
D.
i j + 4k− 2
E.
i + j + 2k
SECTION A – continued
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Question 12Giventhatθistheacuteanglebetweenthevectors
a i j k= − + −2 2 and
b i + 4j k,= − +4 7 thensin(2θ)isequalto
A. 2 2
B. 4 2
9
C. 2 2
9
D. 2 2
3
E. 4 2
3
Question 13Forthevectors
a i j k, b i 4j k and c i j k= + − = − − + = − − +3 2 6 λ tobelinearly dependent,thevalueofλ mustbeA. 0B. 1C. 2D. 3E. 4
Question 14
Thepositionvector
r( )t ofamassof3kgaftertseconds,wheret≥0,isgivenby
r( ) i j.t t t t= + −
10 16 4
32 3
Theforce,innewtons,actingonthemasswhent =2secondsisA. 16
j
B. 32
j
C. 48
j
D. 30 144
i j+
E. 16
Question 15Aliftacceleratesfromrestataconstantrateuntilitreachesaspeedof3ms–1.Itcontinuesatthisspeedfor10secondsandthendeceleratesataconstantratebeforecomingtorest.Thetotaltraveltimefortheliftis 30seconds.Thetotaldistance,inmetres,travelledbytheliftisA. 30B. 45C. 60D. 75E. 90
SECTION A – continuedTURN OVER
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Question 16Anobjectofmass2kgistravellinghorizontallyinastraightlineataconstantvelocityofmagnitude2ms–1.Theobjectishitinsuchawaythatitdeflects30°fromitsoriginalpath,continuingatthesamespeedinastraightline.Themagnitude,correcttotwodecimalplaces,ofthechangeofmomentum,inkgms–1,oftheobjectisA. 0.00B. 0.24C. 1.04D. 1.46E. 2.07
Question 17Aballisthrownverticallyupwardswithaninitialvelocityof7 6 ms–1,andissubjecttogravityandairresistance.Theaccelerationoftheballisgivenbyẍ=–(9.8+0.1v2),wherevms–1isitsvelocitywhenitisataheightofxmetresabovegroundlevel.Themaximumheight,inmetres,reachedbytheballisA. 5 loge(4)
B. loge 31( )
C. 5 2
21π
D. 5 loge(2)
E. 7 2
3π
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END OF SECTION A
Question 18ConsiderarandomvariableX withprobabilitydensityfunction
f xx x
x x( )
or =
≤ ≤< >
2 0 10 0 1
,,
Ifalargenumberofsamples,eachofsize100,istakenfromthisdistribution,thenthedistributionofthe
samplemeans,X ,willbeapproximatelynormalwithmeanE X( ) = 23andstandarddeviationsd X( )equal
to
A. 2
60
B. 2
6
C. 1
180
D. 1
18
E. 2
30
Question 19Bagsofpeanutsarepackedbyamachine.Themassesofthebagsarenormallydistributedwithastandarddeviationofthreegrams.Theminimumsizeofasamplerequiredtoensurethatthemanufacturercanbe98%confidentthatthesamplemeaniswithinonegramofthepopulationmeanisA. 37B. 38C. 48D. 49E. 60
Question 20Nitrogenoxideemissionsforacertaintypeofcarareknowntobenormallydistributedwithameanof0.875g/kmandastandarddeviationof0.188g/km.Fortworandomlyselectedcars,theprobabilitythattheirnitrogenoxideemissionsdifferbymorethan 0.5g/kmisclosesttoA. 0.030B. 0.060C. 0.960D. 0.970E. 0.977
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TURN OVER
CONTINUES OVER PAGE
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SECTION B – Question 1–continued
Question 1 (10marks)
Inthecomplexplane,Listhelinewithequation z z i+ = − −2 1 3 .
a. Verifythatthepoint(0,0)liesonL. 1mark
b. ShowthatthecartesianformoftheequationofLis 3 .y x= − 2marks
c. ThelineLcanalsobeexpressedintheform z z z− = −1 1 ,wherez1 ∈ C.
Findz1incartesianform. 2marks
SECTION B
Instructions for Section BAnswerallquestionsinthespacesprovided.Unlessotherwisespecified,anexactanswerisrequiredtoaquestion.Inquestionswheremorethanonemarkisavailable,appropriateworkingmust beshown.Unlessotherwiseindicated,thediagramsinthisbookarenotdrawntoscale.Taketheacceleration due to gravitytohavemagnitudegms–2,whereg=9.8
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SECTION B – continuedTURN OVER
d. Find, in cartesian form, the point(s) of intersection of L and the graph of z = 4. 2 marks
e. Sketch L and the graph of z = 4 on the Argand diagram below. 2 marks
5
4
3
2
1
–1
–2
–3
–4
–5
O–5 –4 –3 –2 –1 1 2 3 4 5
Im(z)
Re(z)
f. Find the area of the sector defined by the part of L where Re(z) ≥ 0, the graph of z = 4 where Re(z) ≥ 0, and the imaginary axis where Im(z) > 0. 1 mark
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SECTION B – Question 2–continued
Question 2 (10marks)
Considerthefunction f withrule f xx xx
( ) .=+ +−
2
21
1
a. i. Statetheequationsoftheasymptotesofthegraphof f. 2marks
ii. Statethecoordinatesofthestationarypointsandthepointofinflection.Giveyouranswerscorrecttotwodecimalplaces. 2marks
iii. Sketchthegraphof f fromx =–6tox =6(endpointcoordinatesarenotrequired)onthesetofaxesbelow,labellingtheturningpointsandthepointofinflectionwiththeircoordinatescorrecttotwodecimalplaces.Labeltheasymptoteswiththeirequations. 3marks
y
x–6 –4 –2 2 4 6
2
1
O
–1
–2
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SECTION B – continuedTURN OVER
Considerthefunction fk withrule f x x x kxk ( ) ,=+ +−
2
2 1wherek ∈ R.
b. Forwhatvaluesofkwill fk haveno stationary points? 2marks
c. Forwhatvalueof k willthegraphof fk haveapointofinflectionlocatedonthey-axis? 1mark
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SECTION B – Question 3–continued
Question 3 (9marks)
h
60
40
20
O
–20
–30 30
y
x
Theverticalcross-sectionofabarrelisshownabove.Theradiusofthecircularbase (alongthex-axis)is30cmandtheradiusofthecirculartopis70cm.Thecurvedsidesofthe
cross-sectionshownarepartsoftheparabolawithrule y x= −
2
80454
. Theheightofthebarrelis 50cm.
a. i. Showthatthevolumeofthebarrelisgivenbyπ ( ) .900 800
50+∫ y dy 1mark
ii. Findthevolumeofthebarrelincubiccentimetres. 1mark
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SECTION B – continuedTURN OVER
Thebarrelisinitiallyfullofwater.WaterbeginstoleakfromthebottomofthebarrelsuchthatdVdt
hA
=−8000π cubiccentimetrespersecond,whereaftertsecondsthedepthofthewateris
hcentimetres,thevolumeofwaterremaininginthebarrelisVcubiccentimetresandtheuppermostsurfaceareaofthewaterisAsquarecentimetres.
b. Showthat dVdt
hh
=−
+400
4 45. 2marks
c. Finddhdt
intermsofh. Expressyouranswerintheform −+a hb chπ ( )
,2 wherea,bandcare
positiveintegers. 3marks
d. Usingadefiniteintegralintermsofh,findthetime,in hours,correcttoonedecimalplace,takenforthebarreltoempty. 2marks
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SECTION B – Question 4–continued
Question 4 (10marks)AsnowboarderattheWinterOlympicsleavesaskijumpatanangleofθdegreestothehorizontal,risesupintheair,performsvarioustricksandthenlandsatadistancedownastraightslopethatmakesanangleof45°tothehorizontal,asshownbelow.LettheoriginO ofacartesiancoordinate systembeatthepointwherethesnowboarderleavesthejump,withaunitvectorinthepositivexdirectionbeingrepresentedby
i andaunitvectorinthepositiveydirectionbeingrepresentedby
j.Distancesaremeasuredinmetresandtimeismeasuredinseconds.Thepositionvectorofthesnowboardertsecondsafterleavingthejumpisgivenby
r( ) i j, 0t t t t t t t= −( ) + − +( ) ≥6 0 01 6 3 4 9 0 013 2 3. . .
θ°
45°O
y
x
path of snowboarder
slope
a. Findtheangleθ °. 2marks
b. Findthespeed,inmetrespersecond,ofthesnowboarderwhensheleavesthejumpatO. 1mark
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SECTION B – continuedTURN OVER
c. FindthemaximumheightaboveOreachedbythesnowboarder.Giveyouranswerinmetres,correcttoonedecimalplace. 2marks
d. Showthatthetimespentintheairbythesnowboarderis60 3 1
49
+( )seconds. 3marks
e. Findthetotaldistancethesnowboardertravelswhileairborne.Giveyouranswerinmetres,correcttotwodecimalplaces. 2marks
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SECTION B – Question 5–continued
Question 5 (12marks)Apalletofbricksweighing500kgsitsonaroughplaneinclinedatanangleofα°tothehorizontal,
where tan( ) .α° =724
Thepalletisconnectedbyalightinextensiblecablethatpassesoverasmooth
pulleytoahangingcontainerofmassm kilogramsinwhichthereis10Lofwater.ThepalletofbricksisheldinequilibriumbythetensionTnewtonsinthecableandafrictionalresistanceforceof50g newtonsactingupandparalleltotheplane.Taketheweightforceexertedby1Lofwatertobegnewtons.
α°
a. Labelallforcesactingonboththepalletofbricksandthehangingcontaineronthediagramabove,whenthepalletofbricksisinequilibriumasdescribed. 1mark
b. Showthatthevalueofmis80. 3marks
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SECTION B – Question 5–continuedTURN OVER
Suddenlythewateriscompletelyemptiedfromthecontainerandthepalletofbricksbeginstoslidedowntheplane.Thefrictionalresistanceforceof50gnewtonsactinguptheplanecontinuestoactonthepallet.
c. Findthedistance,inmetres,travelledbythepalletafter10seconds. 3marks
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SECTION B – continued
d. Whenthepalletreachesavelocityof3ms–1,waterispouredbackintothecontainerataconstantrateof2Lpersecond,whichinturnretardsthemotionofthepalletmovingdowntheplane.Let tbethetime,inseconds,afterthecontainerbeginstofill.
i. Writedown,intermsoft,anexpressionforthetotalmassofthehangingcontainerandthewateritcontainsaftertseconds.Giveyouranswerinkilograms. 1mark
ii. Showthattheaccelerationofthepalletdowntheplaneisgivenby g tt
( )5290
2−+
−ms for t∈[ )0 5, . 2marks
iii. Findthevelocityofthepalletwhent =4.Giveyouranswerinmetrespersecond,correcttoonedecimalplace. 2marks
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SECTION B – continuedTURN OVER
CONTINUES OVER PAGE
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SECTION B – Question 6–continued
Question 6 (9marks)Apaintcompanyclaimsthatthemeantimetakenforitspainttodrywhenmotorvehiclesarerepairedis3.55hours,withastandarddeviationof0.66hours.Assumethatthedryingtimeforthepaintfollowsanormaldistributionandthattheclaimedstandarddeviationvalueisaccurate.
a. LettherandomvariableX representthemeantimetakenforthepainttodryforarandomsampleof36motorvehicles.
WritedownthemeanandstandarddeviationofX . 2marks
Atacrashrepaircentre,itwasfoundthatthemeantimetakenforthepaintcompany’spainttodryon36randomlyselectedvehicleswas3.85hours.Themanagementofthiscrashrepaircentrewasnothappyandbelievedthattheclaimregardingthemeantimetakenforthepainttodrywastoolow.Totestthepaintcompany’sclaim,astatisticaltestwascarriedout.
b. WritedownsuitablenullandalternativehypothesesH0andH1respectivelytotestwhetherthemeantimetakenforthepainttodryislongerthanclaimed. 1mark
c. Writedownanexpressionforthepvalueofthestatisticaltestandevaluateitcorrecttothreedecimalplaces. 2marks
d. Usinga1%levelofsignificance,statewithareasonwhetherthecrashrepaircentreisjustifiedinbelievingthatthepaintcompany’sclaimofameantimetakenforitspainttodryof 3.55hoursistoolow. 1mark
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e. Atthe1%levelofsignificance,findthesetofsamplemeanvaluesthatwouldsupporttheconclusionthatthemeantimetakenforthepainttodryexceeded3.55hours.Giveyouranswerinhours,correcttothreedecimalplaces. 2marks
f. Ifthetrue meantimetakenforthepainttodryis3.83hours,findtheprobabilitythatthepaintcompany’sclaimisnotrejectedatthe1%levelofsignificance,assumingthestandarddeviationforthepainttodryisstill0.66hours.Giveyouranswercorrecttotwodecimalplaces. 1mark
END OF QUESTION AND ANSWER BOOK
SPECIALIST MATHEMATICS
Written examination 2
FORMULA SHEET
Instructions
This formula sheet is provided for your reference.A question and answer book is provided with this formula sheet.
Students are NOT permitted to bring mobile phones and/or any other unauthorised electronic devices into the examination room.
Victorian Certificate of Education 2019
© VICTORIAN CURRICULUM AND ASSESSMENT AUTHORITY 2019
SPECMATH EXAM 2
Specialist Mathematics formulas
Mensuration
area of a trapezium 12 a b h+( )
curved surface area of a cylinder 2π rh
volume of a cylinder π r2h
volume of a cone 13π r2h
volume of a pyramid 13 Ah
volume of a sphere 43π r3
area of a triangle 12 bc Asin ( )
sine ruleaA
bB
cCsin ( ) sin ( ) sin ( )
= =
cosine rule c2 = a2 + b2 – 2ab cos (C )
Circular functions
cos2 (x) + sin2 (x) = 1
1 + tan2 (x) = sec2 (x) cot2 (x) + 1 = cosec2 (x)
sin (x + y) = sin (x) cos (y) + cos (x) sin (y) sin (x – y) = sin (x) cos (y) – cos (x) sin (y)
cos (x + y) = cos (x) cos (y) – sin (x) sin (y) cos (x – y) = cos (x) cos (y) + sin (x) sin (y)
tan ( ) tan ( ) tan ( )tan ( ) tan ( )
x y x yx y
+ =+
−1tan ( ) tan ( ) tan ( )
tan ( ) tan ( )x y x y
x y− =
−+1
cos (2x) = cos2 (x) – sin2 (x) = 2 cos2 (x) – 1 = 1 – 2 sin2 (x)
sin (2x) = 2 sin (x) cos (x) tan ( ) tan ( )tan ( )
2 21 2x x
x=
−
3 SPECMATH EXAM
TURN OVER
Circular functions – continued
Function sin–1 or arcsin cos–1 or arccos tan–1 or arctan
Domain [–1, 1] [–1, 1] R
Range −
π π2 2
, [0, �] −
π π2 2
,
Algebra (complex numbers)
z x iy r i r= + = +( ) =cos( ) sin ( ) ( )θ θ θcis
z x y r= + =2 2 –π < Arg(z) ≤ π
z1z2 = r1r2 cis (θ1 + θ2)zz
rr
1
2
1
21 2= −( )cis θ θ
zn = rn cis (nθ) (de Moivre’s theorem)
Probability and statistics
for random variables X and YE(aX + b) = aE(X) + bE(aX + bY ) = aE(X ) + bE(Y )var(aX + b) = a2var(X )
for independent random variables X and Y var(aX + bY ) = a2var(X ) + b2var(Y )
approximate confidence interval for μ x z snx z s
n− +
,
distribution of sample mean Xmean E X( ) = µvariance var X
n( ) = σ2
SPECMATH EXAM 4
END OF FORMULA SHEET
Calculus
ddx
x nxn n( ) = −1 x dxn
x c nn n=+
+ ≠ −+∫ 11
11 ,
ddxe aeax ax( ) = e dx
ae cax ax= +∫ 1
ddx
xxelog ( )( ) = 1 1
xdx x ce= +∫ log
ddx
ax a axsin ( ) cos( )( ) = sin ( ) cos( )ax dxa
ax c= − +∫ 1
ddx
ax a axcos( ) sin ( )( ) = − cos( ) sin ( )ax dxa
ax c= +∫ 1
ddx
ax a axtan ( ) sec ( )( ) = 2 sec ( ) tan ( )2 1ax dxa
ax c= +∫ddx
xx
sin−( ) =−
12
1
1( ) 1 0
2 21
a xdx x
a c a−
=
+ >−∫ sin ,
ddx
xx
cos−( ) = −
−
12
1
1( ) −
−=
+ >−∫ 1 0
2 21
a xdx x
a c acos ,
ddx
xx
tan−( ) =+
12
11
( ) aa x
dx xa c2 2
1
+=
+
−∫ tan
( )( )
( ) ,ax b dxa n
ax b c nn n+ =+
+ + ≠ −+∫ 11
11
( ) logax b dxa
ax b ce+ = + +−∫ 1 1
product rule ddxuv u dv
dxv dudx
( ) = +
quotient rule ddx
uv
v dudx
u dvdx
v
=
−
2
chain rule dydx
dydududx
=
Euler’s method If dydx
f x= ( ), x0 = a and y0 = b, then xn + 1 = xn + h and yn + 1 = yn + h f (xn)
acceleration a d xdt
dvdt
v dvdx
ddx
v= = = =
2
221
2
arc length 1 2 2 2
1
2
1
2
+ ′( ) ′( ) + ′( )∫ ∫f x dx x t y t dtx
x
t
t( ) ( ) ( )or
Vectors in two and three dimensions
r = i + j + kx y z
r = + + =x y z r2 2 2
� � � � �ir r i j k= = + +ddt
dxdt
dydt
dzdt
r r1 2. cos( )= = + +r r x x y y z z1 2 1 2 1 2 1 2θ
Mechanics
momentum
p v= m
equation of motion
R a= m