contents · contents limits 3 deriv atives 14 integrals 33 appendix 42 ... dif fer ential equation...

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Co

nte

nts

Lim

its

3

De

riva

tiv

es

14

Inte

gra

ls3

3

Ap

pe

nd

ix4

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isre

vie

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uid

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ara

Ad

ib.

Po

rtio

ns

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its”

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ivat

ives

”ch

apte

rsar

eb

ased

off

the

Cal

culu

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ikib

oo

kav

aila

ble

on

the

Inte

rnet

athttp://en.wikibooks.org/wiki/

Calculus

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.In

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all

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iew

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ject

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atso

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or

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ut

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nn

ecti

on

wit

hth

eu

seo

rp

erfo

rman

ceo

fth

isre

vie

wg

uid

eo

ro

ther

do

cum

ents

wh

ich

are

refe

ren

ced

by

or

lin

ked

toin

this

rev

iew

gu

ide.

Gra

ph

icC

red

its

•F

igu

re0.

1o

np

age

24is

ap

ub

lic

do

mai

ng

rap

hic

by

Ind

uct

ivel

oad

:http://commons.wikimedia.org/wiki/File:Maxima_and_Minima.svg

•F

igu

re0.

2o

np

age

26is

ap

ub

lic

do

mai

ng

rap

hic

by

Ind

uct

ivel

oad

:http://commons.wikimedia.org/wiki/File:X_cubed_(narrow).svg

2

Ap

pen

dix

Tri

go

no

me

tric

Ide

nti

tie

s

Py

thag

ore

an

Ide

nti

tie

s

1.si

n2θ

+co

s2θ

=1

2.1

+ta

n2θ

=se

c2θ

3.1

+co

t2θ

=cs

c2θ

Qu

oti

en

tId

en

titi

es

1.

tan

θ=

sin

θ

cosθ

2.

cotθ

=co

sin

θ

Su

mo

fTw

oA

ng

les

1.si

n(A

+B)

=si

nA

cosB

+co

sA

sin

B

2.co

s(A

+B)

=co

sA

cosB

−si

nA

sin

B

42

Lim

its

Th

isch

apte

rw

aso

rig

inal

lyd

esig

ned

for

ate

sto

nli

mit

sad

min

iste

red

by

Jean

ine

Len

no

nto

her

Mat

h12

H(4

H/

Pre

calc

ulu

s)cl

ass

on

Ap

ril

2,20

08.

Itw

asla

ter

up

dat

edw

ith

an“A

dd

end

um

”se

ctio

n(p

age

12)

for

ate

sto

nli

mit

sad

min

iste

red

by

Jon

ath

anC

her

nic

kto

his

AP

1C

alcu

lus

BC

clas

so

nS

epte

mb

er18

,200

8.

Intr

od

uc

tio

n

Ali

mit

loo

ks

atw

hat

hap

pen

sto

afu

nct

ion

wh

enth

ein

pu

tap

pro

ach

es,

bu

td

oes

no

tn

eces

sari

lyre

ach

,ace

rtai

nv

alu

e.T

he

gen

eral

no

tati

on

for

ali

mit

isb

elo

w.

lim

x→

cf(

x)

=L

Th

isis

read

as“t

he

lim

ito

ff(

x)

asx

app

roac

hes

cis

L.”

Info

rma

lD

efi

nit

ion

of

aL

imit

Lis

the

lim

ito

ff(

x)

asx

app

roac

hes

c.

Th

ev

alu

eo

ff(

x)

com

escl

ose

toL

wh

enx

iscl

ose

(bu

tn

ot

nec

essa

rily

equ

al)

toc.

Itca

nb

ere

pre

sen

ted

by

eith

ero

fth

efo

llo

win

gfo

rms,

wit

hth

efo

rmer

bei

ng

far

mo

reco

mm

on

.

•li

mx→

cf(

x)

=L

•f(

x)

→L

asx

→c

Ru

les

No

wth

ata

lim

ith

asb

een

info

rmal

lyd

efin

ed,

som

eru

les

that

are

use

ful

for

man

ipu

lati

ng

ali

mit

are

list

ed.

Ide

nti

tie

s

Th

efo

llo

win

gid

enti

ties

assu

me

lim

x→

cf(

x)

=L

and

lim

x→

cg(x

)=

M.

Usi

ng

thes

eid

enti

ties

,o

ther

rule

s

can

be

ded

uce

d.

1A

Pis

are

gis

tere

dtr

adem

ark

of

the

Co

lleg

eB

oar

d,

wh

ich

was

no

tin

vo

lved

inth

ep

rod

uct

ion

of,

and

do

esn

ot

end

ors

e,th

isp

rod

uct

.

3

Sc

ala

rM

ult

ipli

ca

tio

n

Asc

alar

isa

con

stan

t.W

hen

afu

nct

ion

ism

ult

ipli

edb

ya

con

stan

t,sc

alar

mu

ltip

lica

tio

nis

per

form

ed.

lim

x→

ckf(

x)

=k·l

imx→

cf(

x)

=kL

Ad

dit

ion

lim

x→

c[f

(x)+

g(x

)]=

lim

x→

cf(

x)+

lim

x→

cg(x

)=

L+

M

Su

btr

ac

tio

n

lim

x→

c[f

(x)−

g(x

)]=

lim

x→

cf(

x)−

lim

x→

cg(x

)=

L−

M

Mu

ltip

lic

ati

on

lim

x→

c[f

(x)·g

(x)]

=li

mx→

cf(

x)·l

imx→

cg(x

)=

L·M

Div

isio

n

lim

x→

c

f(x)

g(x

)=

lim

x→

cf(

x)

lim

x→

cg(x

)=

L M,w

her

eM

6=0

Co

ns

tan

tR

ule

Th

eco

nst

ant

rule

stat

esth

atif

f(x)

=k

isco

nst

ant

for

allx

,th

enth

eli

mit

asx

app

roac

hes

cm

ust

be

equ

alto

k.

lim

x→

ck

=k

Ide

nti

tyR

ule

Th

eid

enti

tyru

lest

ates

that

iff(

x)

=x

,th

enth

eli

mit

asx

app

roac

hes

cis

equ

alto

c.

lim

x→

cx

=c

4

Ex

am

ple

dy

dx

=yx

dy y

=xdx

ln|y

|=

1 2x2

eln

|y|

=e

1 2x

2

y=

e1 2x

2+

C

Inte

gra

tio

nB

yS

ub

sti

tuti

on

Inte

gra

tio

nb

ysu

bst

itu

tio

nis

am

eth

od

for

inte

gra

tin

ga

com

po

siti

on

of

fun

ctio

n,

wh

enth

een

tire

inte

gra

lca

nb

eex

pre

ssed

inte

rms

of

con

stan

ts,u

,an

ddu

.

Inte

gra

tio

nb

ysu

bst

itu

tio

nm

ayb

eu

sed

inco

mb

inat

ion

wit

hru

les

for

inv

erse

trig

on

om

etri

cfu

nc-

tio

ns.

Tri

go

no

me

tric

Ide

nti

tie

s

Tri

go

no

met

ric

iden

titi

es(p

age

42)

can

be

use

dto

sim

pli

fyex

pre

ssio

ns

bef

ore

or

afte

rin

teg

rati

ng

.

41

Slo

pe

Fie

lds

Slo

pe

fiel

ds

(als

ok

no

wn

asd

irec

tio

nfi

eld

s)ar

ea

log

ical

exte

nsi

on

toin

itia

lv

alu

ep

rob

lem

sas

they

pro

vid

ea

sket

cho

fth

ed

iffe

ren

tial

equ

atio

nfo

ran

yv

alu

eo

fC

.

Ata

ble

con

tain

ing

the

val

ue

of

dy

dx

(th

efu

nct

ion

’ssl

op

e)at

dif

fere

ntx

and

yv

alu

esis

use

dto

crea

tea

slo

pe

fiel

d.

Ap

pro

ach

es

Th

ese

app

roac

hes

red

uce

the

tim

ere

qu

ired

tom

ake

or

anal

yze

slo

pe

fiel

ds

and

the

po

ssib

ilit

yo

fm

akin

ger

rors

.

Pa

tte

rns

Ho

rizo

nta

lP

att

ern

Wh

enth

ed

iffe

ren

tial

equ

atio

no

nly

con

tain

sth

ele

tter

y(e

.g.

dy

dx

=y

),th

ere

isa

ho

rizo

nta

lp

atte

rn.

Ve

rtic

al

Pa

tte

rnW

hen

the

dif

fere

nti

aleq

uat

ion

on

lyco

nta

ins

the

lett

erx

(e.g

.dy

dx

=x

),th

ere

isa

ver

tica

lp

atte

rn.

Dir

ec

tio

no

fS

lop

e

Det

erm

inin

gw

het

her

the

slo

pes

of

po

ints

ina

cert

ain

vic

init

yar

ep

osi

tiv

eo

rn

egat

ive

isu

sefu

lfo

rco

mp

arin

gsl

op

efi

eld

s.

Ze

ro/N

oS

lop

e

Det

erm

inin

gw

her

eth

esl

op

eso

fp

oin

tsar

ein

fin

ity

(ver

tica

lan

du

nd

efin

ed)

and

wh

ere

they

are

zero

isu

sefu

lfo

rco

mp

arin

gsl

op

efi

eld

s.

Se

pa

rati

on

of

Va

ria

ble

s

Sep

arat

ion

of

var

iab

les

iso

ne

met

ho

dto

iso

late

var

iab

les

ina

dif

fere

nti

able

equ

atio

n.

Th

ese

par

ated

var

iab

les

can

then

be

inte

gra

ted

.

Ifdy

dx

=g(x

)h(y

),th

endy

h(y

)=

g(x

)dx

.

Bas

ical

ly,

dy

dx

isb

ein

gtr

eate

das

afr

acti

on

,wh

ich

can

be

can

be

sep

arat

ed.

40

Po

we

rR

ule

Th

eru

lefo

rp

rod

uct

sm

any

tim

esre

sult

sin

det

erm

inin

gth

ep

ow

erru

le.

lim

x→

cf(

x)n

=(

lim

x→

cf(

x))

n

Fin

din

gL

imit

s

Ifc

isin

the

do

mai

no

fth

efu

nct

ion

and

the

fun

ctio

nca

nb

eb

uil

to

ut

of

rati

on

al,

trig

on

om

etri

c,lo

gar

ith

mic

and

exp

on

enti

alfu

nct

ion

s,th

enth

eli

mit

issi

mp

lyth

ev

alu

eo

fth

efu

nct

ion

atc.

Ifc

isn

ot

inth

ed

om

ain

of

the

fun

ctio

n,

then

inm

any

case

s(a

sw

ith

rati

on

alfu

nct

ion

s)th

ed

om

ain

of

the

fun

ctio

nin

clu

des

all

of

the

po

ints

nea

rc,

bu

tn

otc.

An

exam

ple

wo

uld

be

ifo

ne

wan

ted

to

fin

dli

mx→

0

x x,

wh

ere

the

do

mai

nin

clu

des

all

real

nu

mb

ers

exce

pt0.

Inth

atca

se,

on

ew

ou

ldw

ant

to

fin

da

sim

ilar

fun

ctio

n,

wit

hth

eh

ole

fill

edin

.T

he

lim

ito

fth

isfu

nct

ion

atc

wil

lb

eth

esa

me,

wh

ile

the

fun

ctio

nis

the

sam

eat

all

po

ints

no

teq

ual

toc.

Th

eli

mit

defi

nit

ion

dep

end

so

nf(

x)

on

lyat

the

po

ints

wh

ere

xis

clo

seto

cb

ut

no

teq

ual

toit

.A

nd

sin

ceth

ed

om

ain

of

the

new

fun

ctio

nin

clu

des

c,

on

eca

nn

ow

(ass

um

ing

it’s

stil

lb

uil

to

ut

of

rati

on

al,

trig

on

om

etri

c,lo

gar

ith

mic

and

exp

on

enti

alfu

nct

ion

s)ju

stev

alu

ate

the

fun

ctio

nat

cas

bef

ore

.

Inth

eab

ov

eex

amp

le,

this

isea

sy;

can

celi

ng

the

x’s

giv

es1,

wh

ich

equ

als

x /x

atal

lp

oin

tsex

cep

t0.

Th

us,

lim

x→

0

x x=

lim

x→

01

=1.

Ing

ener

al,

wh

enco

mp

uti

ng

lim

its

of

rati

on

alfu

nct

ion

s,it

’sa

go

od

idea

to

loo

kfo

rco

mm

on

fact

ors

inth

en

um

erat

or

and

den

om

inat

or.

Do

es

No

tE

xis

t

No

teth

atth

eli

mit

mig

ht

no

tex

ist

atal

l.T

her

ear

ea

nu

mb

ero

fw

ays

inw

hic

hth

isca

no

ccu

r.

No

tS

am

efr

om

Bo

thS

ide

s

Ale

ft-h

and

edli

mit

isd

iffe

ren

tfr

om

the

rig

ht-

han

ded

lim

ito

fth

esa

me

var

iab

le,v

alu

e,an

dfu

nct

ion

.S

ince

,th

ele

ft-h

and

edli

mit6=

rig

ht-

han

ded

lim

it,t

he

lim

itd

oes

no

tex

ist.

Th

isin

clu

des

case

sin

wh

ich

the

lim

ito

fa

cert

ain

sid

ed

oes

no

tex

ist

(e.g

.li

mx→

2

√x

−2,w

hic

hh

asn

ole

ft-h

and

edli

mit

).

Ga

p

Th

ere

isa

gap

(mo

reth

ana

po

int

wid

e)in

the

fun

ctio

nw

her

eth

efu

nct

ion

isn

ot

defi

ned

.A

san

exam

ple

,in

f(x)

=√

x2

−16,f(

x)

do

esn

ot

hav

ean

yli

mit

wh

en−

4≤

x≤

4.

Th

ere

isn

ow

ayto

“ap

pro

ach

”th

em

idd

leo

fth

eg

rap

h.

No

teal

soth

atth

efu

nct

ion

also

has

no

lim

itat

the

end

po

ints

of

the

two

curv

esg

ener

ated

(atx

=−

4an

dx

=4)

sin

celi

mit

sfr

om

bo

thsi

des

do

no

tex

ist.

5

Ju

mp

Ifth

eg

rap

hsu

dd

enly

jum

ps

toa

dif

fere

nt

lev

el,

ther

eis

no

lim

it.

Th

isis

illu

stra

ted

inth

efl

oo

rfu

nct

ion

(in

wh

ich

the

ou

tpu

tv

alu

eis

the

gre

ates

tin

teg

ern

ot

gre

ater

than

the

inp

ut

val

ue)

.T

he

lim

itd

oes

no

tex

ist

wh

enth

eg

reat

est

inte

ger

fun

ctio

nap

pro

ach

esan

inte

ger

(li

mx→

inte

ger⌊x⌋,

also

wri

tten

as

intx

).|x

| /x

and

x /|x

|ar

eo

ther

exam

ple

so

fg

rap

hs

that

con

tain

jum

ps.

Infi

nit

eO

sc

illa

tio

n

Th

isca

nb

etr

ick

yto

vis

ual

ize.

Ag

rap

hco

nti

nu

ally

rise

sab

ov

ean

db

elo

wa

ho

rizo

nta

lli

ne

asit

app

roac

hes

ace

rtai

nx

-val

ue,

for

inst

ance

infi

nit

y.T

his

oft

enm

ean

sth

atth

eli

mit

do

esn

ot

exis

t,as

the

gra

ph

nev

erap

pro

ach

esa

par

ticu

lar

val

ue.

Ho

wev

er,i

fth

eh

eig

ht

(an

dd

epth

)o

fea

cho

scil

lati

on

dim

inis

hes

asth

eg

rap

hap

pro

ach

esth

ex

-val

ue,

soth

atth

eo

scil

lati

on

sg

etar

bit

rari

lysm

alle

r,th

enth

ere

mig

ht

actu

ally

be

ali

mit

.

Th

eu

seo

fo

scil

lati

on

nat

ura

lly

call

sto

min

dth

etr

igo

no

met

ric

fun

ctio

ns.

An

exam

ple

of

atr

igo

no

-

met

ric

fun

ctio

nth

atd

oes

no

th

ave

ali

mit

asx

app

roac

hes

0is

f(x)

=si

n1 x

.A

sx

get

scl

ose

rto

0,

the

fun

ctio

nk

eep

so

scil

lati

ng

bet

wee

n−

1an

d1.

Inc

om

ple

teG

rap

h

Co

nsi

der

the

foll

ow

ing

exam

ple

.

g(x

)=

{2,

ifx

isra

tio

nal

0,

ifx

isir

rati

on

al

g(x

)d

oes

no

th

ave

ali

mit

.F

or

letx

be

are

aln

um

ber

,g(x

)ca

n’t

hav

ea

lim

itat

x.

No

mat

ter

ho

wcl

ose

on

eg

ets

tox

,th

ere

wil

lb

era

tio

nal

nu

mb

ers

(wh

eng(x

)w

ill

be

2)

and

irra

tio

nal

nu

mb

ers

(wh

eng

wil

lb

e0).

Th

us

g(x

)h

asn

oli

mit

atan

yre

aln

um

ber

.

On

e-S

ide

dL

imit

s

So

met

imes

,it

isn

eces

sary

toco

nsi

der

wh

ath

app

ens

wh

eno

ne

app

roac

hes

anx

val

ue

fro

mo

ne

par

-ti

cula

rd

irec

tio

n.

To

acco

mm

od

ate

for

this

,th

ere

are

on

e-si

ded

lim

its.

Ina

left

-han

ded

lim

it,x

ap-

pro

ach

esa

fro

mth

ele

fth

and

sid

e(n

egat

ive)

.L

ikew

ise,

ina

rig

ht-

han

ded

lim

it,x

app

roac

hes

afr

om

the

rig

ht

han

dsi

de

(po

siti

ve)

.

Fo

rex

amp

le,

lim

x→

2

√x

−2

do

esn

ot

exis

tb

ecau

seth

ere

isn

ole

ft-h

and

edli

mit

.

Th

ele

ft-h

and

edli

mit

,wh

ich

do

esn

ot

exis

t,is

exp

ress

edas

the

foll

ow

ing

.

lim

x→

2−

√x

−2

Th

eri

gh

t-h

and

edli

mit

,wh

ich

equ

als

0,i

sex

pre

ssed

asth

efo

llo

win

g.

lim

x→

2+

√x

−2

=0

6

Me

an

Va

lue

of

De

fin

ite

Inte

gra

ls

Me

an

Va

lue

Th

eav

erag

e(a

rith

met

icm

ean

)y

-val

ue

of

afu

nct

ion

ov

eran

inte

rval

isth

ein

teg

ral

ov

erth

ein

terv

ald

ivid

edb

yth

ele

ng

tho

fth

ein

terv

al.

f avg

=

∫b a[f

(x)d

x]

b−

a

Me

an

Va

lue

Th

eo

rem

Iff

isco

nti

nu

ou

so

nth

ecl

ose

din

terv

al[a

,b],

then

atso

me

po

intc

in[a

,b]

ther

eex

ists

the

foll

ow

ing

:

f(c)

=

∫b a[f

(x)d

x]

b−

a

Init

ial

Va

lue

Pro

ble

ms

Intr

od

uc

tio

n

An

equ

atio

nth

atco

nta

ins

ad

eriv

ativ

eis

call

eda

dif

fere

nti

aleq

uat

ion

.F

or

exam

ple

,dy

dx

=2x

isa

dif

fere

nti

aleq

uat

ion

.E

ver

yd

iffe

ren

tial

equ

atio

no

fa

fun

ctio

nco

rres

po

nd

sto

asp

ecifi

ceq

uat

ion

ata

par

ticu

lar

po

int

(ref

erre

dto

asa

par

ticu

lar

solu

tio

n),

assu

min

gth

ep

oin

tis

inth

efu

nct

ion

’sd

om

ain

.

An

init

ial

val

ue

pro

ble

mp

rov

ides

ad

iffe

ren

tial

equ

atio

nan

da

par

ticu

lar

po

int

thro

ug

hw

hic

hth

efu

nct

ion

pas

ses

thro

ug

h.

Th

esp

ecifi

ceq

uat

ion

isd

eter

min

edb

yca

lcu

lati

ng

the

val

ue

ofC

.

Ex

am

ple

dy

dx

=2x

,y(1

)=

6

∫[

dy

dx

]

=

[2xdx]

y=

x2

+C

6=

(1)2

+C

6=

1+

C

C=

5

y=

x2

+5

39

ax

Ru

le

[ axdx]=

ax

lna

+C

Tri

go

no

me

try

•in

teg

rati

ng

the

der

ivat

ives

of

the

six

trig

on

om

etri

cfu

nct

ion

s

•in

teg

rati

ng

the

der

ivat

ives

of

the

inv

erse

trig

on

om

etri

cfu

nct

ion

s

See

the

the

trig

on

om

etri

cse

ctio

no

fth

ed

eriv

ativ

esch

apte

ro

np

age

20fo

rm

ore

info

rmat

ion

.

Co

ns

tan

t

Ifth

eco

nst

ant

iso

uts

ide

the

trig

on

om

etri

cfu

nct

ion

,u

seth

eco

nst

ant

mu

ltip

lier

rule

(Sec

tio

n).

Ifth

eco

nst

ant

isin

sid

eth

etr

igo

no

met

ric

fun

ctio

n,u

seth

efo

llo

win

gru

le.

[(tr

igkx)d

x]=

(∫[t

rig]k

x)

k+

C

wh

ere

kis

aco

nst

ant.

De

fin

ite

Inte

gra

ls

Ad

dit

ivit

yR

ule

Th

ear

eau

nd

erth

eg

rap

ho

ff(

x)

bet

wee

na

and

bis

the

area

bet

wee

na

and

cp

lus

the

area

bet

wee

nc

and

b.

∫b a[f

(x)d

x]=

∫c a[f

(x)d

x]+

∫b c[f

(x)d

x]

Ze

roR

ule

∫a a[f

(x)d

x]=

0

Ord

er

of

Inte

gra

tio

nR

ule

∫a b[f

(x)d

x]=

∫b a[f

(x)d

x]

38

Infi

nit

eL

imit

s

Lim

its

can

also

inv

olv

elo

ok

ing

atw

hat

hap

pen

sto

f(x)

asx

get

sv

ery

big

.F

or

exam

ple

,co

nsi

der

the

fun

ctio

nf(

x)

=1 x

.A

sx

bec

om

esv

ery

big

,1 x

bec

om

escl

ose

rto

zero

.W

ith

ou

tli

mit

sit

isv

ery

dif

ficu

ltto

talk

abo

ut

this

fact

,b

ecau

se1 x

nev

erac

tual

lyb

eco

mes

zero

.B

ut

the

lan

gu

age

of

lim

its

exis

tsp

reci

sely

tole

to

ne

talk

abo

ut

the

beh

avio

ro

fa

fun

ctio

nas

itap

pro

ach

esso

met

hin

g,

wit

ho

ut

cari

ng

abo

ut

the

fact

that

itw

ill

nev

erg

etth

ere.

Inth

isca

se,

ho

wev

er,

the

sam

ep

rob

lem

asb

efo

reex

ists

;ho

wb

igd

oes

xh

ave

tob

eto

be

sure

that

f(x)

isre

ally

go

ing

tow

ard

s0?

Inth

isca

se,

the

big

ger

xg

ets,

the

clo

ser

f(x)

sho

uld

get

to0.

Rea

lly,

this

mea

ns

that

ho

wev

ercl

ose

on

ew

ants

f(x)

tog

etto

0,o

ne

can

fin

dan

xb

igen

ou

gh

sof(

x)

isth

atcl

ose

.T

his

isw

ritt

enin

asi

mil

arw

ayto

fin

ite

lim

its

and

isre

adas

“th

eli

mit

,as

xap

pro

ach

esin

fin

ity,

equ

als

0,”

or

“as

xap

pro

ach

esin

fin

ity,

the

fun

ctio

nap

pro

ach

es0.”

lim

x→

1 x=

0

Ru

les

Th

eea

sies

tw

ayto

det

erm

ine

lim

its

asx

app

roac

hes

±∞

isb

yu

sin

gth

eg

rap

hin

gca

lcu

lato

rto

mak

eo

bse

rvat

ion

s,o

rb

yp

lug

gin

gin

hig

hv

alu

eso

fp

osi

tiv

ean

dn

egat

ive

nu

mb

ers

ina

calc

ula

tor.

Ho

wev

er,

ther

ear

eth

ree

rule

sfo

rd

eter

min

ing

ali

mit

of

afr

acti

on

anal

yti

call

yas

av

aria

ble

ap-

pro

ach

esin

fin

ity.

Fo

rea

chru

le,o

ne

mu

stlo

ok

atth

ev

aria

ble

so

nb

oth

the

nu

mer

ato

ran

dd

eno

min

a-to

ro

fth

efu

nct

ion

.

Lo

ok

for

the

hig

hes

tte

rm(w

ith

the

hig

hes

tex

po

nen

t)in

the

nu

mer

ato

r.L

oo

kfo

rth

esa

me

inth

ed

eno

min

ato

r.T

hes

eru

les

are

bas

edo

nth

atin

form

atio

n.

Fo

rli

mit

sas

the

var

iab

leap

pro

ach

esin

fin

ity

:

•If

the

exp

on

ent

of

the

hig

hes

tte

rmin

the

nu

mer

ato

rm

atch

esth

eex

po

nen

to

fth

eh

igh

est

term

inth

ed

eno

min

ato

r,th

eli

mit

isth

efr

acti

on

alra

tio

of

the

coef

fici

ents

of

the

hig

hes

tte

rms.

•If

the

nu

mer

ator

has

the

hig

hes

tte

rm,

then

the

frac

tio

nis

call

ed“t

op

hea

vy

”an

dth

eli

mit

isin

fin

ity.

•If

the

den

omin

ator

has

the

hig

hes

tte

rm,

then

the

frac

tio

nis

call

ed“b

ott

om

hea

vy

”an

dth

eli

mit

isze

ro.

Ifth

ere

isn

od

eno

min

ato

rst

ated

,it

isu

nd

erst

oo

dth

atth

ed

eno

min

ato

ris

1o

r1n

0,a

nd

the

lim

itw

ill

be

infi

nit

y.

As

ym

pto

tes

Ali

nea

ras

ym

pto

teis

ast

raig

ht

lin

eth

ata

gra

ph

app

roac

hes

,b

ut

do

esn

ot

bec

om

eid

enti

cal

to.

Asy

mp

tote

sar

efo

rmal

lyd

efin

edu

sin

gli

mit

s.

7

Ve

rtic

al

As

ym

pto

tes

Th

eli

ne

x=

ais

av

erti

cal

asy

mp

tote

for

the

fun

ctio

nf(

x)

ifat

leas

to

ne

of

the

foll

ow

ing

stat

emen

tsis

tru

e.

1.li

mx→

af(

x)

2.li

mx→

a−

f(x)

3.li

mx→

a+

f(x)

Th

eli

mit

sfr

om

bo

thd

irec

tio

ns

do

no

th

ave

tob

eeq

ual

toh

ave

anas

ym

pto

te,b

ut

they

may

be

equ

al.

Ess

enti

ally

,a

ver

tica

las

ym

pto

teo

ccu

rsw

her

eth

eth

ev

alu

eo

fa

lim

itis

po

siti

ve

or

neg

ativ

ein

fin

ity

fro

man

yd

irec

tio

n.

Rec

all

that

this

occ

urs

wh

ere

the

frac

tio

no

fa

fun

ctio

nis

un

defi

ned

(den

om

inat

or

equ

als

zero

).

Re

mo

va

ble

Dis

co

nti

nu

itie

s

Th

efu

nct

ion

f(x)

=x

2−

9x−

3is

con

sid

ered

toh

ave

are

mo

vab

led

isco

nti

nu

ity

atx

=3.

Itis

dis

con

tin

uo

us

atth

atp

oin

tb

ecau

seth

efr

acti

on

then

bec

om

es0 0

wh

ich

isu

nd

efin

ed.

Sta

nd

ard

alg

ebra

icte

chn

iqu

esfo

rsi

mp

lify

ing

frac

tio

ns

and

alg

ebra

icex

pre

ssio

ns

(i.e

.fa

cto

rin

g,m

ul-

tip

lyin

gb

yco

nju

gat

es)

can

be

use

dto

elim

inat

eth

ed

isco

nti

nu

ity.

f(x)

=x2

−9

x−

3=

(x+

3)(

x−

3)

(x−

3)

=x

+3

1·x

−3

x−

3=

x+

3

1·1

=x

+3

Ho

wev

er,

the

fun

ctio

nis

no

tre

ally

con

tin

uo

us,

and

ano

pen

circ

lem

ust

be

left

inth

eg

rap

hat

the

rem

ov

able

dis

con

tin

uit

y.

Ho

rizo

nta

lA

sy

mp

tote

s

Th

eli

ne

y=

ais

ah

ori

zon

tal

asy

mp

tote

for

the

fun

ctio

nf(

x)

ifli

mx→

∞f(

x)

=a

or

lim

x→

−∞

f(x)

=a

.

Ifli

mx→

∞f(

x)

=a

and

lim

x→

−∞

f(x)

=b

,th

enth

efu

nct

ion

f(x)

has

two

asy

mp

tote

sat

y=

aan

dy

=b

.

No

teth

atin

som

efu

nct

ion

s,th

eg

rap

hm

ayp

ass

thro

ug

hth

eh

ori

zon

tal

asy

mp

tote

atan

xv

alu

eo

fze

ro.

Ess

enti

ally

,a

ho

rizo

nta

las

ym

pto

teo

ccu

rsat

the

val

ue

of

ali

mit

wh

ere

xap

pro

ach

esp

osi

tiv

eo

rn

egat

ive

infi

nit

y.

Rec

all

that

rule

sex

ist

for

calc

ula

tin

gth

eth

ev

alu

eo

fa

lim

itw

her

ex

app

roac

hes

po

siti

ve

or

neg

ativ

ein

fin

ity.

Ru

les

Th

eea

sies

tw

ayto

det

erm

ine

lim

its

asx

app

roac

hes

±∞

isb

yu

sin

gth

eg

rap

hin

gca

lcu

lato

rto

mak

eo

bse

rvat

ion

s,o

rb

yp

lug

gin

gin

hig

hv

alu

eso

fp

osi

tiv

ean

dn

egat

ive

nu

mb

ers

ina

calc

ula

tor.

8

Co

ns

tan

tM

ult

ipli

er

Ru

le

[c×

f(x)d

x]=

c

[f(x

)dx]

∫b a[c×

f(x)d

x]=

c

∫b a[f

(x)d

x]

Po

we

rR

ule

[xndx]=

xn

+1

n+

1+

C

∫b a[x

ndx]=

bn

+1

−a

n+

1

n+

1

wh

ere

nis

aco

nst

ant

exp

on

ent

no

teq

ual

to−

1an

dx6=

0.

Ex

pre

ssio

ns

con

tain

ing

roo

ts(i

.e.

squ

are

roo

ts)

can

be

intr

egra

ted

by

usi

ng

afr

acti

on

alv

alu

efo

rn

(b√

xa

=x

a/

b).

Ex

pre

ssio

ns

con

tain

ing

alg

ebra

icm

on

om

ials

inth

ed

eno

min

ato

ro

fa

frac

tio

nca

nb

e

inte

gra

ted

by

inv

erti

ng

the

sig

no

fn

(1 xn

=x

−n

).

Lo

ga

rith

ms

1 xR

ule

∫[

dx x

]

=ln

|x|+

C

∫b a

[

dx x

]

=ln

|b|−

ln|a

|

wh

ere

x6=

0.

ex

Ru

le

∫[

ekxdx]

=ekx

k+

C

∫b a

[

ekxdx]

=ekb

k−

eka

k

wh

ere

kis

aco

nst

ant.

37

Co

roll

ary

Inte

gra

tio

nan

dd

iffe

ren

tiat

ion

are

inv

erse

so

fea

cho

ther

.

Iff

isco

nti

nu

ou

so

nth

ecl

ose

din

terv

al[a

,b]

then

:

d dx

[∫

x a[f

(t)d

t]

]

=f(

x)

d du

[∫

u a[f

(t)dt]

]

=f(

u)d

u

Inte

gra

lR

ule

s

Ru

les

for

calc

ula

tin

gth

ein

teg

rals

of

gen

eral

fun

ctio

ns

hav

eb

een

dev

elo

ped

.A

sa

resu

lt,i

tis

po

ssib

leto

calc

ula

teth

ein

teg

rals

of

aw

ide

var

iety

of

fun

ctio

ns.

Inm

any

case

sth

eu

seo

fm

ult

iple

rule

sar

ere

qu

ired

.

Inth

efo

llo

win

gru

les,

Cre

pre

sen

tsth

eco

nst

ant

of

inte

gra

tio

n.

Co

ns

tan

tF

un

cti

on

Th

ed

efin

ite

inte

gra

lo

fa

con

stan

tfu

nct

ion

isa

rect

ang

lew

ith

the

hei

gh

tb

ein

gth

eco

nst

ant

and

the

wid

thb

ein

gth

ein

terv

alo

fin

teg

rati

on

.

[cdx]=

cx

+C

∫b a[c

dx]=

c(b

−a)

wh

ere

cis

aco

nst

ant.

Ad

dit

ion

/Su

btr

ac

tio

nR

ule

Iff(

x)

and

g(x

)ar

eco

nti

nu

ou

so

nth

ecl

ose

din

terv

al[a

,b],

then

:

[(f(

x)±

g(x

))dx]=

[f(x

)dx]±

[g(x

)dx]+

C

∫b a[(

f(x)±

g(x

))dx]=

∫b a[f

(x)d

x]±

∫b a[g

(x)d

x]

As

are

sult

,o

ne

can

tak

ean

equ

atio

n,

bre

akit

up

into

term

s,fi

gu

reo

ut

the

defi

nit

ein

teg

rals

ind

ivid

-u

ally

,an

db

uil

dth

ean

swer

bac

ku

p.

36

Ho

wev

er,

ther

ear

eth

ree

rule

sfo

rd

eter

min

ing

ali

mit

of

afr

acti

on

anal

yti

call

yas

av

aria

ble

ap-

pro

ach

esin

fin

ity.

Fo

rea

chru

le,o

ne

mu

stlo

ok

atth

ev

aria

ble

so

nb

oth

the

nu

mer

ato

ran

dd

eno

min

a-to

ro

fth

efu

nct

ion

.

Lo

ok

for

the

hig

hes

tte

rm(w

ith

the

hig

hes

tex

po

nen

t)in

the

nu

mer

ato

r.L

oo

kfo

rth

esa

me

inth

ed

eno

min

ato

r.T

hes

eru

les

are

bas

edo

nth

atin

form

atio

n.

•If

the

exp

on

ent

of

the

hig

hes

tte

rmin

the

nu

mer

ato

rm

atch

esth

eex

po

nen

to

fth

eh

igh

est

term

inth

ed

eno

min

ato

r,th

eli

mit

isth

efr

acti

on

alra

tio

of

the

coef

fici

ents

of

the

hig

hes

tte

rms.

•If

the

nu

mer

ator

has

the

hig

hes

tte

rm,

then

the

frac

tio

nis

call

ed“t

op

hea

vy

”an

dth

eli

mit

isin

fin

ity.

•If

the

den

omin

ator

has

the

hig

hes

tte

rm,

then

the

frac

tio

nis

call

ed“b

ott

om

hea

vy

”an

dth

eli

mit

isze

ro.

Ifth

ere

isn

od

eno

min

ato

rst

ated

,it

isu

nd

erst

oo

dth

atth

ed

eno

min

ato

ris

1o

r1n

0,a

nd

the

lim

itw

ill

be

infi

nit

y.

Sk

etc

hin

gw

ith

As

ym

pto

tes

Ase

ries

of

step

sca

nb

eta

ken

tosk

etch

wit

has

ym

pto

tes.

As

are

sult

,cu

rves

may

be

sket

ched

wit

ho

ut

ag

rap

hin

gca

lcu

lato

r.

1.F

ind

the

x-i

nte

rcep

tb

yse

ttin

gy

equ

alto

zero

.

2.F

ind

the

y-i

nte

rcep

tb

yse

ttin

gx

equ

alto

zero

.

3.F

ind

the

ho

rizo

nta

las

ym

pto

te(s

).

4.F

ind

the

ver

tica

las

ym

pto

tes(

s).

5.P

lot

the

x-i

nte

rcep

tan

dy

-in

terc

ept.

6.S

ket

chth

eas

ym

pto

te(s

).

7.F

ind

the

lim

its

of

bo

thsi

des

of

the

ver

tica

las

ym

pto

teb

yu

sin

gte

stp

oin

ts.

8.S

ket

chth

ecu

rve

usi

ng

the

det

erm

ined

info

rmat

ion

and

the

sket

ched

asy

mp

tote

s.

Inso

me

pro

ble

ms

on

lyli

mit

sw

ill

be

pro

vid

ed.

Fro

mth

ese

lim

its

ho

rizo

nta

lan

dv

erti

cal

asy

mp

-to

tes

can

be

det

erm

ined

.W

hil

eth

ex

-in

terc

ept

and

y-i

nte

rcep

tar

en

ot

pro

vid

ed,

itis

stil

lp

oss

ible

tosk

etch

the

gra

ph

.T

he

sket

chw

ill

be

less

accu

rate

,b

ut

that

isac

cep

tab

lew

hen

pro

vid

edw

ith

lim

ited

info

rmat

ion

.

Co

nti

nu

ity

De

fin

itio

n

Th

efo

rmal

defi

nit

ion

of

con

tin

uit

yis

sim

ple

.

Iff(

x)

isd

efin

edo

nan

op

enin

terv

alco

nta

inin

gc,t

hen

f(x)

issa

idto

be

con

tin

uo

us

atc

ifan

do

nly

ifth

eli

mit

asx

app

roac

hes

ceq

ual

sf(

c).

lim

x→

cf(

x)

=f(

c)

9

No

teth

atfo

rf(

x)

tob

eco

nti

nu

ou

sat

c,t

he

defi

nit

ion

req

uir

esth

ree

con

dit

ion

s.

1.f(

x)

isd

efin

edat

c

a)f(

c)

exis

ts

2.T

he

lim

itas

xap

pro

ach

esc

exis

ts.

a)li

mx→

cf(

x)

exis

ts

3.T

he

lim

itan

df(

c)

are

equ

al.

a)f(

c)

=li

mx→

cf(

x)

Ifan

yo

fth

ese

do

no

th

old

then

f(x)

isn

ot

con

tin

uo

us

atc.

No

tice

ho

wth

isre

late

sto

the

idea

of

con

tin

uit

y.T

ob

eco

nti

nu

ou

s,th

efu

nct

ion

mu

stb

eu

nif

orm

ly“s

mo

oth

”(e

.g.

no

“gap

s,”

bre

aks,

or

shar

ptu

rns/

corn

ers)

wit

hin

anin

terv

al.

Afu

nct

ion

issa

idto

be

con

tin

uo

us

ifit

isco

nti

nu

ou

sat

ever

yp

oin

tc

init

sd

om

ain

.

Afu

nct

ion

may

be

con

tin

uo

us

ata

cert

ain

po

int,

bu

tn

ot

aco

nti

nu

ou

sfu

nct

ion

(th

rou

gh

ou

t).

Lik

e-w

ise,

ad

isco

nti

nu

ou

sfu

nct

ion

may

be

con

tin

uo

us

ata

cert

ain

po

int.

Re

mo

va

ble

Dis

co

nti

nu

itie

s

dis

co

nti

nu

ity

po

int

wh

ere

afu

nct

ion

isn

ot

con

tin

uo

us

Ifth

ere

isa

“gap

”o

ne

po

int

wid

eo

na

gra

ph

(f(c

)d

oes

no

tex

ist)

or

ifth

ere

isa

“ju

mp

”o

ne

po

int

wid

eo

na

gra

ph

(f(c

)6=

lim

x→

cf(

x))

,th

ed

isco

nti

nu

ity

isre

mo

vab

le.

Gap

dis

con

tin

uit

ies

(lim

x→

cf(

x)

do

esn

ot

ex-

ist)

,ju

mp

dis

con

tin

uit

ies

(f(c

)6=

lim

x→

cf(

x))

,an

din

fin

ite

osc

illa

tio

nd

isco

nti

nu

itie

sar

en

on

-rem

ov

able

.

Th

efu

nct

ion

f(x)

=x

2−

9x−

3is

con

sid

ered

toh

ave

are

mo

vab

led

isco

nti

nu

ity

atx

=3.

Itis

dis

con

tin

uo

us

atth

atp

oin

tb

ecau

seth

efr

acti

on

then

bec

om

es0 0

wh

ich

isu

nd

efin

ed.

Th

eref

ore

the

fun

ctio

nfa

ils

the

ver

yfi

rst

con

dit

ion

of

con

tin

uit

y.

Ifth

efu

nct

ion

issl

igh

tly

mo

difi

ed,

the

dis

con

tin

uit

yca

nb

ere

mo

ved

and

the

fun

ctio

nb

eco

mes

con

-ti

nu

ou

s.S

tan

dar

dal

geb

raic

tech

niq

ues

for

sim

pli

fyin

gfr

acti

on

san

dal

geb

raic

exp

ress

ion

s(e

.g.

fac-

tori

ng

,mu

ltip

lyin

gb

yco

nju

gat

es)

can

be

use

d.

To

mak

eth

efu

nct

ion

f(x)

con

tin

uo

us,

f(x)

mu

stb

esi

mp

lifi

ed.

f(x)

=x2

−9

x−

3=

(x+

3)(

x−

3)

(x−

3)

=x

+3

x−

3

x−

3=

x+

3

1=

x+

3

As

lon

gas

x6=

3,t

he

fun

ctio

nf(

x)

can

be

sim

pli

fied

tog

eta

new

fun

ctio

ng(x

).

g(x

)=

{x

+3,

ifx6=

3

6,

ifx

=3

No

teth

atth

efu

nct

ion

g(x

)is

no

tth

esa

me

asth

eo

rig

inal

fun

ctio

nf(

x),

bec

ause

g(x

)h

asth

eex

tra

po

int(3

,6).

g(x

)is

no

wd

efin

edfo

rx

=3,a

nd

ther

efo

reco

nti

nu

ou

s.

10

Gra

ph

ing

Ca

lcu

lato

r

Th

ese

inst

ruct

ion

sar

ed

esig

ned

for

aT

I-84

Plu

sca

lcu

lato

r,b

ut

they

may

use

do

no

ther

Tex

asIn

stru

-m

ents

gra

ph

ing

calc

ula

tors

,th

ou

gh

slig

ht

mo

difi

cati

on

may

be

nec

essa

ry.

Un

less

oth

erw

ise

spec

ified

,th

eg

rap

hin

gca

lcu

lato

rsh

ou

ldb

ein

rad

ian

mo

de.

De

fin

ite

Inte

gra

lR

ec

tan

gu

lar

Ap

pro

xim

ati

on

s

Inso

me

case

sit

may

be

easi

ero

rre

qu

ired

toca

lcu

late

rect

ang

ula

rap

pro

xim

atio

ns

of

defi

nit

ein

teg

rals

usi

ng

the

gra

ph

ing

calc

ula

tor,

esp

ecia

lly

wh

enu

sin

ga

larg

en

um

ber

of

rect

ang

les.

Th

ep

rog

ramRAM

mu

stb

ead

ded

toth

eca

lcu

lato

r’s

mem

ory

.O

nce

inst

alle

d,

set

the

y1

of

the

calc

u-

lato

r’s

gra

ph

toth

efu

nct

ion

bei

ng

inte

gra

ted

and

run

the

pro

gra

mw

ithPRGM−→

RAM

.

De

fin

ite

Inte

gra

lC

alc

ula

tio

ns

Inso

me

case

sit

may

be

easi

ero

rre

qu

ired

toca

lcu

late

defi

nit

ein

teg

rals

usi

ng

the

gra

ph

ing

calc

ula

tor,

esp

ecia

lly

wh

enth

efu

nct

ion

isto

oco

mp

lex

.It

can

also

be

use

dto

chec

ko

ne’

san

swer

.

Fu

nd

am

en

tal

Th

eo

rem

of

Ca

lcu

lus

Ev

ery

con

tin

uo

us

fun

ctio

nh

asan

anti

der

ivat

ive.

Pa

rtI

Iff

isco

nti

nu

ou

so

nth

ecl

ose

din

terv

al[a

,b]

and

F(x

)=

∫x a[f

(t)d

t]o

nth

ecl

ose

din

terv

al[a

,b],

then

Fis

dif

fere

nti

able

on

the

op

enin

terv

al(a

,b)

and

F′ (

x)

=f(

x)

for

allx

inth

eo

pen

inte

rval

(a,b

).

By

defi

nit

ion

F(x

)is

the

anti

der

ivat

ive

off(

x)

inth

eo

pen

inte

rval

(a,b

).

Pa

rtII

Iff

isco

nti

nu

ou

so

nth

ecl

ose

din

terv

al[a

,b]

and

Fis

anan

tid

eriv

ativ

eo

ff,

then

:

∫b a[f

(x)d

x]=

F(b

)−

F(a

)

Itis

ther

efo

rep

oss

ible

toca

lcu

late

ad

efin

ite

inte

gra

lu

sin

gru

les

for

anti

der

ivat

ives

(in

defi

nit

ein

te-

gra

ls).

35

Re

cta

ng

ula

rA

pp

rox

ima

tio

nM

eth

od

Rec

tan

gu

lar

Ap

pro

xim

atio

nM

eth

od

(RA

M)

isa

met

ho

do

fes

tim

atin

gd

efin

ite

inte

gra

lsb

yca

lcu

lati

ng

the

area

of

ace

rtai

nn

um

ber

of

rect

ang

les.

Ala

rger

nu

mb

ero

fre

ctan

gle

sw

ill

giv

ea

mo

reac

cura

tees

tim

ate.

Le

ftR

ec

tan

gu

lar

Ap

pro

xim

ati

on

Me

tho

d(L

RA

M)

∫b a[f

(x)d

x]≈

∆x(f

(a)+

f(a

+∆

x)+···+

f(b

−2∆

x)+

f(b

−∆

x))

wh

ere

∆x

isth

ew

idth

of

the

rect

ang

les

(b−

an

)an

dn

isth

en

um

ber

of

rect

ang

les.

Rig

ht

Re

cta

ng

ula

rA

pp

rox

ima

tio

nM

eth

od

(RR

AM

)

∫b a[f

(x)d

x]≈

∆x(f

(a+

∆x)+

f(a

+2∆

x)+···+

f(b

−∆

x)+

f(b))

wh

ere

∆x

isth

ew

idth

of

the

rect

ang

les

(b−

an

)an

dn

isth

en

um

ber

of

rect

ang

les.

Mid

po

int

Re

cta

ng

ula

rA

pp

rox

ima

tio

nM

eth

od

(MR

AM

)

∫b a[f

(x)d

x]≈

∆x(f

(a+

∆x 2)+

f(a

+∆

x)+···+

f(b

−∆

x)+

f(b

−∆

x 2))

wh

ere

∆x

isth

ew

idth

of

the

rect

ang

les

(b−

an

)an

dn

isth

en

um

ber

of

rect

ang

les.

Tra

pe

zo

ida

lA

pp

rox

ima

tio

nM

eth

od

∫b a[f

(x)d

x]≈(

1 2

)

(∆x)( f

(a)+

2f(

a+

∆x)+···+

2f(

b−

∆x)+

f(b))

wh

ere

∆x

isth

ew

idth

of

the

trap

ezo

ids

(b−

an

)an

dn

isth

en

um

ber

of

trap

ezo

ids.

An

inte

gra

lap

pro

xim

ated

wit

hth

isru

leo

na

con

cav

e-u

pfu

nct

ion

wil

lb

ean

ov

eres

tim

ate

bec

ause

the

trap

ezo

ids

incl

ud

eal

lo

fth

ear

eau

nd

erth

ecu

rve

and

exte

nd

ov

erit

.U

sin

gth

ism

eth

od

on

aco

nca

ve-

do

wn

fun

ctio

ny

ield

san

un

der

esti

mat

eb

ecau

sear

eais

un

acco

un

ted

for

un

der

the

curv

e,b

ut

no

ne

isco

un

ted

abo

ve.

34

Pro

pe

rtie

s

Iff(

x)

and

g(x

)ar

eco

nti

nu

ou

s,th

enth

efo

llo

win

gar

eal

soco

nti

nu

ou

s:

•f(

x)+

g(x

)

•f(

x)·g

(x)

•f(

x)−

g(x

)

•f(

x)

g(x

),g

6=0

•k×

f(x),

wh

ere

kis

aco

nst

ant

Inte

rme

dia

teV

alu

eT

he

ore

m

Ag

rap

ho

fa

con

tin

uo

us

fun

ctio

nh

asn

ob

reak

s,so

ap

oin

tb

etw

een

two

x-v

alu

esh

asa

y-v

alu

eb

etw

een

the

y-v

alu

eso

fth

ere

spec

tiv

ex

-val

ues

.

Ifa

fun

ctio

nis

con

tin

uo

us

on

the

clo

sed

inte

rval

[a,b

],th

enfo

rev

ery

val

ue

kb

etw

een

f(a)

and

f(b)

ther

eis

av

alu

ec

on

[a,b

]su

chth

atf(

c)

=k

.

Th

isca

nb

eu

sed

toap

pro

xim

ate

wh

enth

ey

-val

ue

of

afu

nct

ion

wil

lb

ea

cert

ain

val

ue

(e.g

.th

ex

-val

ue

wh

eny

=4).

Ca

lcu

lati

ng

Co

nti

nu

itie

s

On

esh

ou

ldb

eab

leto

det

erm

ine

wh

ere

afu

nct

ion

isd

isco

nti

nu

ou

s.In

som

eca

ses,

on

em

ayb

ere

qu

ired

tod

eter

min

eth

ev

alu

e(s)

of

var

iab

le(s

)in

rule

(s)

of

afu

nct

ion

soth

atth

efu

nct

ion

wil

lb

eco

nti

nu

ou

s.A

syst

emo

feq

uat

ion

sis

req

uir

edw

hen

ther

ear

em

ult

iple

var

iab

les.

Tri

go

no

me

tric

Fu

nc

tio

ns

Inm

ost

case

s,li

mit

sw

ith

trig

on

om

etri

cfu

nct

ion

sca

nb

etr

eate

dth

esa

me

way

aso

ther

lim

its.

On

eca

nsu

bst

itu

tein

toth

eex

pre

ssio

nif

po

ssib

le,o

ru

seth

eg

rap

hin

gca

lcu

lato

r.

Ifd

ivid

eb

yze

roo

ccu

rs,

on

em

ayel

imin

ate

rem

ov

able

dis

con

tin

uit

ies

ifth

eyex

ist

or

use

the

gra

ph

-in

gca

lcu

lato

r.In

som

eca

ses,

fact

ori

ng

toel

imin

ate

rem

ov

able

dis

con

tin

uit

ies

can

on

lyb

ed

on

eif

trig

on

om

etri

cid

enti

ties

are

use

dfi

rst.

No

teW

hen

gra

ph

ing

,st

ayin

rad

ian

mo

de

asth

eli

mit

sar

ep

rov

ided

inra

dia

nm

od

eu

nle

ssst

ated

oth

erw

ise.

Tri

go

no

me

tric

Ide

nti

tie

s

Tri

go

no

met

ric

iden

titi

es(p

age

42)

can

be

use

dto

sim

pli

fyex

pre

ssio

ns

bef

ore

or

afte

rfi

nd

ing

ali

mit

.

11

Ad

de

nd

um

Th

isse

ctio

nw

asd

esig

ned

for

ate

sto

nli

mit

sad

min

iste

red

by

Jon

ath

anC

her

nic

kto

his

AP

2C

alcu

lus

BC

clas

so

nS

epte

mb

er18

,200

8.It

isn

ot

cov

ered

inM

ath

12H

/4H

.

Fu

rth

er

Tri

go

no

me

tric

Ide

nti

tie

s

Th

ese

iden

titi

esca

nb

eu

sed

for

the

sam

ep

urp

ose

asth

eo

ther

trig

on

om

etri

cid

enti

ties

.T

ou

seth

ese

iden

titi

es,

the

lim

its

may

nee

dto

be

mu

ltip

lied

by

ace

rtai

nfa

cto

ro

rse

par

ated

bas

edo

nth

eru

les

on

pag

e3.

Sin

e

lim

x→

0

sin

x

x=

1

Co

sin

e

lim

x→

0

1−

cosx

x=

0

Sq

ue

eze

(Sa

nd

wic

h)

Th

eo

rem

Th

esq

uee

zeth

eore

m,

also

kn

ow

nas

the

san

dw

ich

theo

rem

,is

use

dto

fin

dth

eli

mit

of

afu

nct

ion

by

com

par

iso

nw

ith

two

oth

erfu

nct

ion

sw

ho

seli

mit

sar

ek

no

wn

or

easi

lyco

mp

ute

d.

Itre

fers

toa

fun

ctio

nf(

x)

wh

ose

val

ues

are

squ

eeze

db

etw

een

the

val

ues

of

two

oth

erfu

nct

ion

sg(x

)an

dh(x

),b

oth

of

wh

ich

hav

eth

esa

me

lim

itL

.If

the

val

ue

off(

x)

istr

app

edb

etw

een

the

val

ues

of

the

two

fun

ctio

ns

g(x

)an

dh(x

),th

ev

alu

eso

ff(

x)

mu

stal

soap

pro

ach

L.

Ifth

efo

llo

win

gar

etr

ue:

1.g(x

)≤

f(x)≤

h(x

)fo

ral

lx

no

teq

ual

toc

2.li

mx→

cg(x

)=

lim

x→

ch(x

)=

L

Th

enli

mx→

cf(

x)

=L

.

Ex

am

ple

:

lim

x→

0x

sin

1 x

2A

Pis

are

gis

tere

dtr

adem

ark

of

the

Co

lleg

eB

oar

d,

wh

ich

was

no

tin

vo

lved

inth

ep

rod

uct

ion

of,

and

do

esn

ot

end

ors

e,th

isp

rod

uct

.

12

Inte

gra

ls

Th

isch

apte

rw

asd

esig

ned

for

ate

sto

nin

teg

rals

adm

inis

tere

db

yJo

nat

han

Ch

ern

ick

toh

isA

P5

Cal

-cu

lus

BC

clas

so

nN

ov

emb

er26

,200

8.It

isn

ot

cov

ered

inM

ath

12H

/4H

.

De

fin

ite

Inte

gra

ls

De

fin

itio

n

de

fin

ite

inte

gra

lar

eab

etw

een

acu

rve

and

the

x-a

xis

(are

au

nd

ern

eath

the

x-a

xis

isn

egat

ive)

Afi

nit

en

um

ber

of

rect

ang

les

can

be

use

dto

esti

mat

eth

isar

ea.

Ala

rger

nu

mb

ero

fre

ctan

gle

sw

ill

giv

ea

mo

reac

cura

tees

tim

ate,

and

anin

fin

ite

nu

mb

ero

fre

ctan

gle

sca

ng

ive

anex

act

answ

er.

∫b a[f

(x)d

x]≈

Ak

=

n ∑ k=

1

ak

=a

1+

a2

+···+

an

−1

+a

n

Rie

ma

nn

Su

ms

Th

isar

eaca

nb

eex

pre

ssed

asth

ein

fin

ite

lim

ito

fR

iem

ann

sum

s.A

sn

get

sla

rger

the

wid

tho

fth

ere

ctan

gle

sg

ets

smal

ler

and

wh

enn

app

roac

hes

infi

nit

y,th

eex

act

area

isca

lcu

late

d.

Iff(

x)

isa

con

tin

uo

us

on

the

clo

sed

inte

rval

[a,b

],th

ed

efin

ite

inte

gra

lo

ff(

x)

bet

wee

na

and

bis

:

∫b a[f

(x)]

dx

=li

mn

→∞

(

n ∑ k=

1

f(ck))

(

b−

a

n

)

wh

ere

ck

are

sam

ple

po

ints

inth

ein

terv

al.

No

tati

on

Wh

enco

nsi

der

ing

the

exp

ress

ion

∫b a[f

(x)]

dx

,th

efu

nct

ion

f(x)

isca

lled

the

inte

gra

nd

and

the

inte

rval

[a,b

]is

the

inte

rval

of

inte

gra

tio

n.a

and

bar

eth

elo

wer

and

up

per

lim

its

of

inte

gra

tio

n,r

esp

ecti

vel

y.

5A

Pis

are

gis

tere

dtr

adem

ark

of

the

Co

lleg

eB

oar

d,

wh

ich

was

no

tin

vo

lved

inth

ep

rod

uct

ion

of,

and

do

esn

ot

end

ors

e,th

isp

rod

uct

.

33

Ex

tre

me

Va

lue

Th

eo

rem

Iff

isco

nti

nu

ou

so

nth

ein

terv

al[a

,b],

fh

asb

oth

am

axim

um

and

am

inim

um

val

ue

inth

ein

terv

al.

No

teth

atb

rack

ets

[]re

fer

toa

clo

sed

inte

rval

incl

ud

ing

the

end

po

ints

wh

ile

par

enth

eses

()

refe

rto

anin

terv

aln

ot

incl

ud

ing

the

end

po

ints

.

Me

an

Va

lue

Th

eo

rem

Iff

isco

nti

nu

ou

so

nth

ein

terv

al[a

,b]

and

dif

fere

nti

able

on

the

inte

rval

(a,b

),th

ere

exis

tsa

po

intc

on

(a,b

)su

chth

atf′

(c)

=f(

b)−

f(a)

b−

a.

Ino

ther

wo

rds,

som

ewh

ere

on

the

inte

rval

the

slo

pe

of

the

tan

gen

tli

ne

equ

als

(at

leas

to

nce

)th

esl

op

eo

fth

ese

can

tli

ne

con

nec

tin

gth

etw

oen

dp

oin

ts.

Ro

lle

’sT

he

ore

m

Ro

lle’

sT

heo

rem

isa

spec

ial

case

of

the

Mea

nV

alu

eT

heo

rem

.

Iff

isco

nti

nu

ou

so

nth

ein

terv

al[a

,b],

dif

fere

nti

able

on

the

inte

rval

(a,b

),an

df(

a)

=f(

b),

then

ther

eex

ists

ap

oin

tc

on

(a,b

)su

chth

atf′

(c)

=0.

32

No

teth

atth

esi

ne

of

any

thin

gis

inth

ein

terv

al[−

1,1

].In

oth

erw

ord

s,−

1≤

sin

x≤

1fo

ral

lx

).A

sa

resu

lt,f

or

all

no

nze

rox

,−1×

| x|≤

xsi

n1 x≤

| x| .

Sim

pli

fied

,th

ism

ean

s−

| x|≤

xsi

n1 x≤

| x| .

Sin

ce

lim

x→

0−

| x|=

lim

x→

0| x

|=

0,

lim

x→

0x

sin

1 x=

0.

En

dB

eh

av

ior

Th

een

db

ehav

ior

of

ag

rap

hd

escr

ibes

ho

wit

app

ears

asx

app

roac

hes

infi

nit

yto

the

rig

ht

(xin

crea

ses)

or

toth

ele

ft(x

dec

reas

es).

En

db

ehav

ior

isex

pre

ssed

asa

beh

avio

rm

od

el.

Th

eb

ehav

ior

mo

del

of

ag

rap

hd

epen

ds

on

the

hig

hes

to

rder

term

inth

eeq

uat

ion

.In

rati

on

alex

pre

ssio

ns

(fra

ctio

ns)

,th

isw

ou

ldb

eth

ed

ivis

ion

of

the

hig

hes

to

rder

term

inth

en

um

erat

or

by

the

hig

hes

to

rder

term

inth

ed

eno

min

ato

r.

Fo

rex

amp

le,t

he

beh

avio

rm

od

elo

f2x5

+x4

−x2

+1

3x2

−5x

+7

is2x5

3x2

.T

he

lim

itas

xap

pro

ach

esb

oth

po

siti

ve

and

neg

ativ

ein

fin

ity

wo

uld

be

po

siti

ve

infi

nit

y.

Dif

feri

ng

Be

hav

ior

So

met

imes

,rig

ht-

han

dan

dle

ft-h

and

beh

avio

rd

iffe

r.

Ifth

efu

nct

ion

isf(

x)

and

its

left

-han

db

ehav

ior

mo

del

isg(x

),li

mx→

∞−

f(x)

g(x

)=

1.

Lik

ewis

e,if

the

fun

c-

tio

nis

f(x)

and

its

rig

ht-

han

db

ehav

ior

mo

del

ish(x

),li

mx→

∞+

f(x)

h(x

)=

1.

Ex

am

ple

:f(

x)

=x

+e−

x

lim

x→

∞−

x+

e−

x

e−

x=

lim

x→

∞−

x

e−

x+

lim

x→

∞−

e−

x

e−

x=

0+

1=

1.

Th

eref

ore

,y=

e−

xis

the

left

-han

db

ehav

ior

mo

del

.

lim

x→

∞+

x+

e−

x

x=

lim

x→

∞+

x x=

lim

x→

∞+

e−

x

x=

1+

0=

1.

Th

eref

ore

,y=

xis

the

rig

ht-

han

db

ehav

ior

mo

del

.

13

Deri

vati

ves

Th

isch

apte

rw

aso

rig

inal

lyd

esig

ned

for

ate

sto

nd

eriv

ativ

esad

min

iste

red

by

Jean

ine

Len

no

nto

her

Mat

h12

H(4

H/

Pre

calc

ulu

s)cl

ass

on

Ap

ril

18,

2008

.It

was

up

dat

edfo

ra

qu

izo

nth

ed

eriv

ativ

eso

ftr

igo

no

met

ric

fun

ctio

ns

on

Ap

ril

29,

2008

,an

dla

ter

up

dat

edw

ith

an“A

dd

end

um

”se

ctio

n(p

age

27)

for

ate

sto

nd

eriv

ativ

esad

min

iste

red

by

Jon

ath

anC

her

nic

kto

his

AP

3C

alcu

lus

BC

clas

so

nO

cto

ber

14,2

008.

Intr

od

uc

tio

n

Th

esl

op

eo

fa

curv

eca

nn

ot

be

det

erm

ined

by

usi

ng

the

form

ula

m=

y2−

y1

x2−

x1

,bu

tth

esl

op

eso

fta

ng

ent

lin

esd

raw

nto

acu

rve

can

be

det

erm

ined

.T

ocr

eate

anin

fin

ite

nu

mb

ero

fta

ng

ent

lin

es,

two

po

ints

on

the

curv

em

ust

be

“pu

shed

”to

get

her

soth

atth

eir

dis

tan

ce,h

,ap

pro

ach

esze

ro.

Th

eco

nce

pt

of

ali

mit

isu

sed

tofi

nd

ad

eriv

ativ

e.T

he

der

ivat

ive

isth

em

tan

(slo

pe

of

tan

gen

tli

ne)

on

acu

rve

ata

spec

ific

po

int.

de

riva

tiv

esl

op

eo

fa

curv

eat

ag

iven

po

int

on

the

curv

e

no

rma

lli

ne

lin

ep

erp

end

icu

lar

toa

tan

gen

tli

ne

atth

ep

oin

to

fta

ng

ency

De

fin

itio

n

f′(x

)=

lim

h→

0

f(x

+h)−

f(x)

h

Ta

ng

en

tL

ine

s

Th

ed

eriv

ativ

eca

nb

eu

sed

toca

lcu

late

the

equ

atio

no

fa

lin

eta

ng

ent

toa

curv

eat

ace

rtai

np

oin

t.T

he

der

ivat

ive

isth

esl

op

eo

fth

eta

ng

ent

lin

e,an

dw

hen

the

coo

rdin

ates

of

the

cert

ain

po

int

on

the

curv

ear

ek

no

wn

,th

eca

lcu

late

dsl

op

ean

dth

eco

ord

inat

eso

fth

ece

rtai

np

oin

to

nth

ecu

rve

(val

ues

can

be

calc

ula

ted

by

plu

gg

ing

into

equ

atio

no

fcu

rve)

can

be

plu

gg

edin

toy

=m

x+

bo

rth

ep

oin

t-sl

op

efo

rmu

lato

det

erm

ine

the

equ

atio

no

fth

eta

ng

ent

lin

e.

Ifth

esl

op

eo

fa

curv

eat

ag

iven

po

int

(der

ivat

ive)

iseq

ual

toth

esl

op

eo

fan

oth

ercu

rve

ata

giv

enp

oin

t,th

enth

etw

ocu

rves

hav

ep

aral

lel

tan

gen

tli

nes

atth

ein

dic

ated

po

ints

.

No

tati

on

Th

ed

eriv

ativ

en

ota

tio

nis

spec

ial

and

un

iqu

ein

mat

hem

atic

s.T

her

ear

etw

ok

ind

so

fn

ota

tio

ns:

Lei

bn

izn

ota

tio

nan

dN

ewto

nia

nn

ota

tio

n.

3A

Pis

are

gis

tere

dtr

adem

ark

of

the

Co

lleg

eB

oar

d,

wh

ich

was

no

tin

vo

lved

inth

ep

rod

uct

ion

of,

and

do

esn

ot

end

ors

e,th

isp

rod

uct

.

14

Bas

edo

nth

ech

ain

rule

(pag

e17

),w

her

eu

isan

yd

iffe

ren

tiab

leex

pre

ssio

n,

d dx[e

u]=

eu×

du

dx

cx

cre

pre

sen

tsa

con

stan

t.T

he

der

ivat

ive

ofcx

iscx×

lnc,c

>0

and

c6=

1.

Bas

edo

nth

ech

ain

rule

(pag

e17

),w

her

ec

isa

con

stan

t,d dx[c

u]=

lnc×

cu×

du

dx

,c>

0an

dc6=

1

lnx

Th

ed

eriv

ativ

eo

fln

xis

1 x,x

>0.

Bas

edo

nth

ech

ain

rule

(pag

e17

),w

her

eu

isan

yd

iffe

ren

tiab

leex

pre

ssio

n,

d dx[l

nu]=

1 u×

du

dx

,u>

0

Lo

ga

rith

ms

Pro

pe

rtie

sT

hes

ep

rop

erti

esh

old

tru

efo

rb

oth

log

and

ln.

•lo

g(x

y)

=lo

gx

+lo

gy

•lo

g(x

/y)

=lo

gx

−lo

gy

•lo

gxa

=a

lnx

Ch

an

ge

of

Ba

se

log

ax

=lo

gx

log

a=

lnx

lna

log

bx

Th

ed

eriv

ativ

eo

flo

gb

xis

1

xln

(b)

.

Bas

edo

nth

ech

ain

rule

(pag

e17

),w

her

eu

isan

yd

iffe

ren

tiab

leex

pre

ssio

n,

d dx[l

og

bu]=

1

uln

(b)×

du

dx

;b>

0,b

6=1,a

nd

u>

0

Lo

ga

rith

mic

Dif

fere

nti

ati

on

Lo

gar

ith

mic

dif

fere

nti

atio

nis

ad

iffe

ren

tiat

ion

pro

cess

use

dto

tak

eth

ed

eriv

ativ

eo

fa

var

iab

lera

ised

toa

var

iab

leo

ro

ther

com

ple

xsi

tuat

ion

s.T

he

nat

ura

llo

g(l

n)

of

bo

thsi

des

of

aneq

uat

ion

are

tak

en,a

nd

the

resu

ltis

imp

lici

tly

dif

fere

nti

ated

.

31

Tri

go

no

met

ric

Fu

nct

ion

Inv

erse

(arc

no

tati

on

)In

ver

se(−

1n

ota

tio

n)

sin

arcs

insi

n−

1

cos

arcc

os

cos−

1

tan

arct

anta

n−

1

cot

arcc

ot

cot−

1

sec

arcs

ecse

c−1

csc

arcc

sccs

c−1

Inth

eta

ble

bel

ow

,uca

nre

pre

sen

tan

yd

iffe

ren

tiab

leex

pre

ssio

n,u

sin

gth

ech

ain

rule

(pag

e17

).

Inv

erse

Tri

go

no

met

ric

Fu

nct

ion

Der

ivat

ive

arcs

inu

1√

1−

u2×

du

dx

,|u|<

1

arcc

osu

−1

√1

−u

du

dx

,|u|<

1

arct

anu

1

1+

u2×

du

dx

arcc

otu

−1

1+

u2×

du

dx

arcs

ecu

1

|u|√

u2

−1×

du

dx

,|u|>

1

arcc

scu

−1

|u|√

u2

−1×

du

dx

,|u|>

1

Str

ate

gie

sfo

rS

imp

lify

ing

Inm

any

dif

ficu

ltp

rob

lem

s(e

.g.

mu

ltip

lech

oic

e)w

her

esi

mp

lify

ing

isn

eces

sary

,th

ere

are

som

est

rate

gie

sfo

rd

oin

gso

.If

sim

pli

fyin

gis

no

tre

qu

ired

,th

ese

stra

teg

ies

are

no

tn

eces

sary

.

•If

anex

pre

ssio

nu

nd

eran

abso

lute

val

ue

isal

way

sp

osi

tiv

e,th

eab

solu

tev

alu

esy

mb

ols

can

be

rem

ov

ed.

•C

om

bin

ete

rms

into

term

sw

ith

aco

mm

on

den

om

inat

or.

•F

acto

ro

ut

var

iab

les

fro

msq

uar

ero

ots

.

Mo

reR

ule

s

Ifth

eo

rig

inal

exp

ress

ion

isa

con

stan

tra

ised

toa

var

iab

lep

ow

er,

use

the

cx

rule

().

Ifth

eo

rig

inal

exp

ress

ion

con

tain

sa

var

iab

lein

the

bas

ean

dex

po

nen

t,lo

gar

ith

mic

dif

fere

nti

atio

n(p

age

31)

mu

stb

eu

sed

.

ex Th

ed

eriv

ativ

eo

fex

isit

self

.

30

Le

ibn

izN

ota

tio

n

Th

eL

eib

niz

no

tati

on

isex

pre

ssed

asdy

dx

,m

ean

ing

“rat

eo

fch

ang

ein

yw

ith

resp

ect

tox

”o

ras

d dx

,w

hic

hli

tera

lly

mea

ns

“der

ivat

ive

wit

hre

spec

tto

x.”

Bec

ause

the

der

ivat

ive

of

fun

ctio

ny

isd

efin

edas

afu

nct

ion

rep

rese

nti

ng

the

slo

pe

of

fun

ctio

ny

,th

ese

con

d(o

rd

ou

ble

)d

eriv

ativ

eis

the

fun

ctio

nre

pre

sen

tin

gth

esl

op

eo

fth

efi

rst

der

ivat

ive

fun

ctio

n.

InL

eib

niz

no

tati

on

,th

isis

wri

tten

as:

d dx

(

dy

dx

)

=d

2y

dx2

New

ton

ian

No

tati

on

Wit

hth

eN

ewto

nia

nn

ota

tio

n,

the

der

ivat

ive

of

the

fun

ctio

nf(

x)

isd

eno

ted

by

f′(x

),an

dit

sse

con

d(o

rd

ou

ble

)d

eriv

ativ

eis

den

ote

db

yf′′ (

x).

Th

isis

read

as“f

do

ub

lep

rim

eo

fx

,”o

r“t

he

seco

nd

der

ivat

ive

off(

x).

Hig

he

rO

rde

rD

eri

va

tiv

es

Th

ese

con

dd

eriv

ativ

eis

the

der

ivat

ive

of

the

der

ivat

ive

of

afu

nct

ion

.S

ub

seq

uen

td

eriv

ativ

esca

nb

eca

lcu

late

db

yca

lcu

lati

ng

the

der

ivat

ive

of

the

pre

vio

us

der

ivat

ive.

Th

efo

llo

win

gar

en

ota

tio

ns

for

der

ivat

ives

of

dif

fere

nt

ord

ers.

Ord

erN

ewto

nia

nN

ota

tio

nL

eib

niz

No

tati

on

Lei

bn

izN

ota

tio

n

Fir

stD

eriv

ativ

ef′

(x)

dy

dx

d dx

[ f(x

)]

Sec

on

dD

eriv

ativ

ef′′ (

x)

d2y

dx2

d2

dx2

[ f(x

)]

Th

ird

Der

ivat

ive

f′′′ (

x)

d3y

dx3

d3

dx3

[f(x

)]

Fo

urt

hD

eriv

ativ

ef(

4)(x

)d

4y

dx4

d4

dx4

[ f(x

)]

Nth

Der

ivat

ive

f(n

)(x

)d

ny

dxn

dn

dxn

[ f(x

)]

On

esh

ou

ldn

ot

wri

tefn

(x)

toin

dic

ate

the

nth

der

ivat

ive,

asth

isis

easi

lyco

nfu

sed

wit

hth

eq

uan

tity

f(x)

all

rais

edto

the

nth

po

wer

.

Ru

les

Ru

les

for

calc

ula

tin

gth

ed

eriv

ativ

eso

fg

ener

alfu

nct

ion

sh

ave

bee

nd

evel

op

ed.

As

are

sult

,it

isp

oss

ible

toca

lcu

late

the

der

ivat

ive

of

aw

ide

var

iety

of

fun

ctio

ns.

Inm

any

case

sth

eu

seo

fm

ult

iple

rule

sar

ere

qu

ired

.

15

Co

ns

tan

tF

un

cti

on

Fo

ran

yco

nst

antc,

d dx[c

]=

0

Th

efu

nct

ion

f(x)

=c

isa

ho

rizo

nta

lli

ne,

wh

ich

has

aco

nst

ant

slo

pe

of

zero

.T

her

efo

re,

itsh

ou

ldb

eex

pec

ted

that

the

der

ivat

ive

of

this

fun

ctio

nis

zero

,re

gar

dle

sso

fth

ev

alu

eo

fx

.It

isim

po

rtan

tto

un

der

stan

dth

ate

and

πar

eco

nst

ants

,an

dth

atth

eir

der

ivat

ive

isth

eref

ore

zero

.

Lin

ea

rF

un

cti

on

Fo

ran

yco

nst

ants

man

dc,

d dx[m

x+

c]=

m

Th

efu

nct

ion

f(x)

=m

x+

cis

ali

ne

wit

ha

slo

pe

ofm

.

Co

ns

tan

tM

ult

ipli

er

Ru

le

Fo

ran

yco

nst

antc,

d dx[c

f(x)]

=c

d dx[f

(x)]

Inth

ed

efin

itio

no

fa

der

ivat

ive,

on

eca

nfa

cto

rc

ou

to

fth

en

um

erat

or

and

then

ou

to

fth

een

tire

lim

it.

Ad

dit

ion

/Su

btr

ac

tio

nR

ule

Fo

rth

eg

iven

fun

ctio

ns

f(x)

and

g(x

),

d dx[f

(x)±

g(x

)]=

d dx[f

(x)]±

d dx[g

(x)]

As

are

sult

,o

ne

can

tak

ean

equ

atio

n,

bre

akit

up

into

term

s,fi

gu

reo

ut

the

der

ivat

ive

ind

ivid

ual

ly,

and

bu

ild

the

answ

erb

ack

up

.

Po

we

rR

ule

Fo

ran

yco

nst

ant

exp

on

entn

,

d dx

[ xn]=

nxn

−1,x

6=0

16

Wit

hu

seo

fth

ech

ain

rule

(pag

e17

),th

ere

lati

on

ship

bet

wee

nth

ed

eriv

ativ

eo

fa

fun

ctio

nan

dth

ed

eriv

ativ

eo

fit

sin

ver

seca

nb

ed

eter

min

ed. f(

f−1(x

))

=x

f′[

f−1(a

)]

×[

f−1]

′ (a)

=1

[

f−1]

′ (a)

=1

f′[

f−1(a

)]

Afu

nct

ion

and

its

inv

erse

hav

ere

cip

roca

lsl

op

esw

ith

rev

erse

d(x

,y)

val

ues

.

[

f−1]

′ (a)

=1

f′[

f−1(a

)]

Ex

am

ple

:f(

x)

=x3

+x

−2,fi

nd[

f−1]

′ (0)

0=

x3

+x

−2

x=

1

f′(x

)=

3x2

+1

f′(1

)=

4

[

f−1]

′ (a)

=1

f′[

f−1(a

)]

[

f−1]

′ (0)

=1

f′[

f−1(0

)]

[

f−1]

′ (0)

=1

f′(1

)[

f−1]

′ (0)

=1 4

Inv

ers

eTri

go

no

me

tric

Fu

nc

tio

ns

Th

ein

ver

setr

igo

no

met

ric

fun

ctio

ns

are

the

inv

erse

fun

ctio

ns

of

the

trig

on

om

etri

cfu

nct

ion

s.T

he

inv

erse

of

the

trig

on

om

etri

cfu

nct

ion

ssi

n,

cos,

tan

,co

t,se

c,an

dcs

cis

arcs

in,

arcc

os,

arct

an,

arcc

ot,

arcs

ec,a

nd

arcc

sc,r

esp

ecti

vel

y.

Th

en

ota

tio

ns

sin

−1,c

os−

1,e

tc.

are

oft

enu

sed

for

arcs

in,a

rcco

s,et

c.,r

esp

ecti

vel

y,b

ut

this

con

ven

tio

nm

ayre

sult

inco

nfu

sio

nb

etw

een

mu

ltip

lica

tiv

ein

ver

sean

dco

mp

osi

tio

nal

inv

erse

sin

ceth

islo

gic

ally

con

flic

tsw

ith

the

stru

ctu

reo

fex

pre

ssio

ns

lik

esi

n2x

,w

hic

hd

on

ot

refe

rto

fun

ctio

nco

mp

osi

tio

nb

ut

rath

erm

ult

ipli

cati

on

.

Eac

hin

ver

setr

igo

no

met

ric

fun

ctio

nh

asa

der

ivat

ive.

29

Imp

lic

itD

iffe

ren

tia

tio

n

ex

pli

cit

rela

tio

ns

hip

fun

ctio

nin

wh

ich

f(x)

isg

iven

inte

rms

ofx

and

con

stan

ts;

for

ever

yx

-val

ue

ther

eis

on

ey

-val

ue

imp

lic

itre

lati

on

sh

ipre

lati

on

ship

bet

wee

ntw

oo

rm

ore

var

iab

les;

two

or

mo

refu

nct

ion

sp

ut

to-

get

her

Ord

inar

yd

iffe

ren

tiat

ion

isex

pli

cit

dif

fere

nti

atio

n.

Imp

lici

td

iffe

ren

tiat

ion

isu

sefu

lw

hen

dif

fere

nti

-at

ing

aneq

uat

ion

that

can

no

tb

eex

pli

citl

yd

iffe

ren

tiat

edb

ecau

seit

isim

po

ssib

leo

rh

ard

tois

ola

tev

aria

ble

s(e

.g.x2

+xy

+y

2=

16).

Inm

any

dif

ficu

ltp

rob

lem

sin

vo

lvin

gim

pli

cit

dif

fere

nti

atio

n(e

.g.

mu

ltip

lech

oic

e),

itis

nec

essa

ryto

sub

stit

ute

the

dep

end

ent

var

iab

le(e

.g.

y)

and

its

der

ivat

ives

(e.g

.dy

dx

,d

2y

dx

2)

bas

edo

nth

eo

rig

inal

equ

atio

no

rp

rev

iou

sd

eter

min

edd

eriv

ativ

eex

pre

ssio

ns.

Ex

am

ple

:x2

+y

2=

1

Ex

pli

cit

Dif

fere

nti

ati

on

x2

+y

2=

1

y2

=1

−x2

y=

±√

1−

x2

y=

±(1

−x2)

1 2

dy

dx

=−

x y

Imp

lic

itD

iffe

ren

tia

tio

n

x2

+y

2=

1

2x

+2y

dy

dx

=0

2y

dy

dx

=−

2x

dy

dx

=−

2x

2y

dy

dx

=−

x y

Inv

ers

eF

un

cti

on

s

inv

ers

efu

nc

tio

n“o

pp

osi

te”

of

afu

nct

ion

;iff(

x)

=a

,f−

1(a

)=

f(x);

refl

ecte

do

ver

lin

ey

=x

Th

eco

mp

osi

tio

no

fa

fun

ctio

nan

dit

sin

ver

seis

xb

ecau

seth

etw

ofu

nct

ion

s“u

nd

o”

each

oth

er.

f(

f−1(x

))

=x

28

Th

isru

leis

actu

ally

inef

fect

inli

nea

req

uat

ion

sto

o,

sin

cexn

−1

=x0

wh

enn

=1,

and

any

real

nu

mb

ero

rv

aria

ble

toth

eze

rop

ow

eris

on

e.

Th

isru

leal

soap

pli

esto

frac

tio

nal

and

neg

ativ

ep

ow

ers.

Th

eref

ore

,

d dx

[√

x]

=d dx

[

x1

/2]

=1 2x

−1

/2

=1

2√

x

Sin

cep

oly

no

mia

lsar

esu

ms

of

mo

no

mia

ls,

usi

ng

this

rule

and

the

add

itio

n/

sub

trac

tio

nru

le(p

age

16)

lets

on

eca

lcu

late

the

der

ivat

ive

of

any

po

lyn

om

ial.

Sim

ple

Fra

cti

on

s

Wh

enta

kin

gth

ed

eriv

ativ

eo

fsi

mp

lefr

acti

on

s,o

ne

can

use

the

foll

ow

ing

sho

rtcu

tto

qu

ick

lyd

oso

.T

he

calc

ula

tio

ns

of

der

ivat

ives

of

mo

reco

mp

lex

frac

tio

ns

req

uir

eu

seo

fth

eq

uo

tien

tru

le.

d dx

[

c xb

]

=d dx

[

cx

−b]

=−

cbx

−b

−1

=−

cbx

−(b

+1)

=−

cb

xb

+1

,wh

ere

cis

aco

nst

ant

Ch

ain

Ru

le

Th

ech

ain

rule

allo

ws

on

eto

calc

ula

teth

ed

eriv

ativ

eo

fan

un

exp

and

edex

pre

ssio

nw

ith

ou

tex

pan

din

gth

eex

pre

ssio

n.

Th

isis

do

ne

by

calc

ula

tin

gth

ed

eriv

ativ

eo

fth

eco

mp

osi

teo

ftw

ofu

nct

ion

s.

Fo

rex

amp

le,

see

the

fun

ctio

nf(

x)

=(a

+b)c

.T

om

ake

this

the

com

po

site

of

two

fun

ctio

ns,

g(x

)=

a+

ban

df(

x)

=g(x

)c.

Th

isfu

nct

ion

can

be

rew

ritt

enas

the

com

po

site

fun

ctio

nf(

g(x

)),

wh

ere

g(x

)

isth

ep

oly

no

mia

l(a

+b

)an

df(

x)

isg(x

)to

the

cth

po

wer

.

Acc

ord

ing

toth

ech

ain

rule

,

d dx[f

(g(x

))]=

f′(g

(x))×

g′ (

x)

An

exam

ple

of

this

situ

atio

nis

f(x)

=(3

x+

4)3

.In

this

case

,g(x

)=

3x+

4an

df(

x)

=g(x

)3.

Acc

ord

ing

toth

ech

ain

rule

,

d dx

[

(3x

+4)3]

=3(3

x+

4)2

×d dx

[ 3x

+4]=

3(3

x+

4)2

×(3

+0)

=9(3

x+

4)2

Pro

du

ct

Ru

le

Th

ed

eriv

ativ

eo

fth

efu

nct

ion

f(x)

=A×

Bw

ou

ldn

otb

ef′

(a)×

f′(b

).T

he

pro

du

ctru

leal

low

so

ne

toco

rrec

tly

calc

ula

teth

ed

eriv

ativ

eo

fth

ep

rod

uct

of

two

fun

ctio

ns.

Acc

ord

ing

toth

ep

rod

uct

rule

, d dx[f

(x)×

g(x

)]=

f(x)×

g′ (

x)+

g(x

f′(x

)

Th

ed

eriv

ativ

eo

fth

ep

rod

uct

of

two

fun

ctio

ns

isth

efi

rst

fun

ctio

nm

ult

ipli

edb

yth

ed

eriv

ativ

eo

fth

eo

ther

fun

ctio

n,a

dd

edto

the

firs

tfu

nct

ion

mu

ltip

lied

by

the

der

ivat

ive

of

the

seco

nd

fun

ctio

n.

Th

em

nem

on

icd

evic

e“o

ne-

D-t

wo

plu

stw

o-D

-on

e”ca

nb

eu

sed

tore

mem

ber

this

rule

.

17

Qu

oti

en

tR

ule

As

wit

hm

ult

iply

ing

,th

ed

eriv

ativ

eo

fa

qu

oti

ent

isn

ot

the

qu

oti

ent

of

the

der

ivat

ives

.T

he

qu

oti

ent

rule

allo

ws

on

eto

corr

ectl

yca

lcu

late

the

der

ivat

ive

of

the

qu

oti

ent

of

two

fun

ctio

ns.

Acc

ord

ing

toth

eq

uo

tien

tru

le, d d

x

[

f(x)

g(x

)

]

=g(x

f′(x

)−

f(x)×

g′ (

x)

g(x

)2

Th

em

nem

on

icd

evic

e“l

ow

-D-h

igh

min

us

hig

h-D

-lo

wo

ver

the

squ

are

of

wh

at’s

bel

ow

”ca

nb

eu

sed

tore

mem

ber

this

rule

.

Ba

sic

Po

lyn

om

ials

Wit

hth

ese

rule

s,th

ed

eriv

ativ

eo

fan

yp

oly

no

mia

lca

nb

ed

eter

min

ed.

Her

eis

ast

ep-b

y-s

tep

exam

ple

of

the

pro

cess

of

calc

ula

tin

gth

ed

eriv

ativ

eo

fa

fair

lysi

mp

lep

oly

no

mia

l.T

he

chai

n,

pro

du

ct,

and

qu

oti

ent

rule

sar

en

ot

cov

ered

.

d dx

[

6x5

+3x2

+3x

+1]

Th

ead

dit

ion

/su

btr

acti

on

rule

(pag

e16

)sp

lits

the

equ

atio

nin

tose

ver

alte

rms.

d dx

[

6x5]

+d dx

[

3x2]

+d dx[3

x]+

d dx[1

]

Th

eco

nst

ant

(pag

e16

)an

dli

nea

r(p

age

16)

rule

sg

etri

do

fso

me

term

s.

d dx

[

6x5]

+d dx

[

3x2]

+3

+0

Th

eco

nst

ant

mu

ltip

lier

rule

(pag

e16

)m

ov

esth

eco

nst

ants

ou

tsid

eo

fth

ed

eriv

ativ

es.

6d dx

[

x5]

+3

d dx[x

]+

3

Th

ep

ow

erru

le(p

age

16)

wo

rks

on

the

ind

ivid

ual

mo

no

mia

ls.

6(

5x4)

+3(2

x)+

3

Sim

pli

fyin

go

bta

ins

the

fin

alan

swer

.

30x4

+6x

+3

Gra

ph

ing

Ca

lcu

lato

r

Inso

me

case

sit

may

be

easi

ero

rre

qu

ired

toca

lcu

late

der

ivat

ives

usi

ng

the

gra

ph

ing

calc

ula

tor.

Itca

nal

sob

eu

sed

toch

eck

on

e’s

answ

er.

Th

ere

are

two

met

ho

ds

of

calc

ula

tin

ga

der

ivat

ive

of

ag

rap

hw

ith

aT

exas

Inst

rum

ents

gra

ph

ing

calc

ula

tor.

Th

ese

inst

ruct

ion

sar

ed

esig

ned

for

aT

I-84

Plu

sca

lcu

lato

r,b

ut

they

may

use

do

no

ther

Tex

asIn

stru

men

tsg

rap

hin

gca

lcu

lato

rs,t

ho

ug

hsl

igh

tm

od

ifica

tio

nm

ayb

en

eces

sary

.

Un

less

oth

erw

ise

spec

ified

,th

eg

rap

hin

gca

lcu

lato

rsh

ou

ldb

ein

rad

ian

mo

de.

18

rec

tan

gu

lar

pri

sm

V=

abc,w

her

ea

,b,a

nd

car

eth

ele

ng

ths

of

the

3si

des

of

the

pri

sm

cy

lin

de

rV

=πr2

h,w

her

er

isth

era

diu

san

dh

isth

eh

eig

ht

of

the

cyli

nd

er

sp

he

reV

=4 3πr3

,wh

ere

rre

pre

sen

tsth

era

diu

so

fth

esp

her

e

Su

rfa

ce

Are

a

cu

be

A=

6a

2,w

her

ea

isth

ele

ng

tho

fth

esi

de

of

each

edg

eo

fth

ecu

be

rec

tan

gu

lar

pri

sm

A=

2ab

+2bc+

2ac,w

her

ea

,b,a

nd

car

eth

ele

ng

ths

of

the

3si

des

of

the

pri

sm

sp

he

reA

=4πr2

,wh

ere

ris

rad

ius

of

the

sph

ere

cy

lin

de

rA

=2πr2

+2πrh

,wh

ere

ris

the

rad

ius

and

his

the

hei

gh

to

fth

ecy

lin

der

Ad

de

nd

um

Th

isse

ctio

nw

asd

esig

ned

for

ate

sto

nd

eriv

ativ

esad

min

iste

red

by

Jon

ath

anC

her

nic

kto

his

AP

4

Cal

culu

sB

Ccl

ass

on

Oct

ob

er14

,200

8.It

isn

ot

cov

ered

inM

ath

12H

/4H

.

Alt

ern

ati

ve

De

fin

itio

no

fD

eri

va

tiv

e

f′(x

)=

lim

x→

a

f(x)−

f(a)

x−

a

Pa

ram

etr

icE

qu

ati

on

s

Par

amet

ric

equ

atio

ns

are

typ

ical

lyd

efin

edb

ytw

oeq

uat

ion

sth

atsp

ecif

yb

oth

the

xan

dy

coo

rdin

ates

of

ag

rap

hu

sin

ga

par

amet

er.

Th

eyar

eg

rap

hed

usi

ng

the

par

amet

er(u

sual

lyt)

tofi

gu

reo

ut

bo

thth

ex

and

yco

ord

inat

es.

Th

ed

eriv

ativ

eo

fth

ep

aram

etri

zed

curv

ex(t

),y(t

)is

:

dy

dx

=

dy

dt

dx

dt

,dx

dt6=

0

Ex

am

ple

:

x=

t,y

=t2

dy

dx

=

dy

dt

dx

dt

=2t 1

=2t

4A

Pis

are

gis

tere

dtr

adem

ark

of

the

Co

lleg

eB

oar

d,

wh

ich

was

no

tin

vo

lved

inth

ep

rod

uct

ion

of,

and

do

esn

ot

end

ors

e,th

isp

rod

uct

.

27

1.M

ath−→

8(8

.n

Der

iv)−→

ente

rw

ith

form

fun

ctio

n,x

,xva

lue−→

En

ter

a)re

pla

cefu

nct

ion

wit

hth

eap

pro

pri

ate

fun

ctio

n

b)

rep

lace

xva

lue

wit

hth

eap

pro

pri

ate

val

ue

2.G

rap

hfu

nct

ion−→

2nd−→

Tra

ce(C

alc)

−→en

terx

val

ue−→

En

ter

a)u

seth

eap

pro

pri

ate

xv

alu

e

Do

es

No

tE

xis

t

Th

eg

rap

hin

gca

lcu

lato

rm

ayd

isp

lay

anin

corr

ect

answ

erw

hen

calc

ula

tin

gd

eriv

ativ

esth

atd

on

ot

exis

t(e

.g.

ata

corn

er).

Gra

ph

ing

calc

ula

tors

lik

eth

eT

I-84

Plu

sca

lcu

late

der

ivat

ives

by

usi

ng

the

sym

met

ric

dif

fere

nce

qu

oti

ent.

f′(x

)=

lim

h→

0

f(x

+h)−

f(x

−h)

2h

Th

ep

rob

lem

wit

hth

ism

eth

od

isth

atth

eca

lcu

lato

rw

ill

actu

ally

calc

ula

teth

eav

erag

esl

op

eo

ver

av

ery

smal

lar

eain

stea

do

fth

etr

ue

der

ivat

ive

(in

stan

tan

eou

ssl

op

e).

At

aco

rner

,th

eav

erag

esl

op

eo

ver

av

ery

smal

lar

eaw

ill

be

zero

,bu

tth

eco

rrec

tan

swer

isth

atth

ed

eriv

ativ

ed

oes

no

tex

ist.

Dif

fere

nti

ab

ilit

y

De

fin

itio

n

Fo

rf(

x)

tob

ed

iffe

ren

tiab

leat

po

intc,t

he

foll

ow

ing

mu

stb

etr

ue:

1.f(

x)

mu

stb

eco

nti

nu

ou

sat

po

intc

a)f(

x)

isd

efin

edat

c

i.f(

c)

exis

ts

b)

Th

eli

mit

asx

app

roac

hes

cex

ists

.

i.li

mx→

cf(

x)

exis

ts

c)T

he

lim

itan

df(

c)

are

equ

al.

i.f(

c)

=li

mx→

cf(

x)

2.T

he

der

ivat

ive

fro

mb

oth

sid

esm

ust

be

equ

al

a)li

mx→

c−

f′(x

)=

lim

x→

c+

f′(x

)

Ifan

yo

fth

ese

do

no

th

old

then

f(x)

isn

ot

dif

fere

nti

able

atc.

No

tice

ho

wth

isre

late

sto

the

idea

of

dif

fere

nti

abil

ity.

To

be

dif

fere

nti

able

,th

efu

nct

ion

mu

sth

ave

au

nif

orm

rate

of

chan

ge

(e.g

.n

oco

rner

s,cu

sps,

or

ver

tica

lta

ng

ents

)w

ith

inan

inte

rval

.

Afu

nct

ion

issa

idto

be

dif

fere

nti

able

ifit

isd

iffe

ren

tiab

leat

ever

yp

oin

tc

init

sd

om

ain

.

Afu

nct

ion

may

be

dif

fere

nti

able

ata

cert

ain

po

int,

bu

tn

ot

ad

iffe

ren

tiab

lefu

nct

ion

(th

rou

gh

ou

t).

Lik

ewis

e,a

no

n-d

iffe

ren

tiab

lefu

nct

ion

may

be

dif

fere

nti

able

ata

cert

ain

po

int.

19

No

tD

iffe

ren

tia

ble

Co

rne

r

Afu

nct

ion

do

esn

ot

hav

ea

der

ivat

ive

ata

corn

er.

lim

x→

a−

f′(x

)6=

lim

x→

a+

f′(x

)

Cu

sp

Acu

spo

ccu

rsw

hen

the

lim

ito

fth

esl

op

efr

om

on

esi

de

of

acu

rve

go

esto

−∞

and

the

oth

ersi

de

of

the

curv

eg

oes

to+

∞.

As

are

sult

,afu

nct

ion

do

esn

ot

hav

ea

der

ivat

ive

ata

cusp

.

lim

x→

a−

f′(x

)6=

lim

x→

a+

f′(x

)

Ve

rtic

al

Ta

ng

en

t

Afu

nct

ion

do

esn

ot

hav

ea

der

ivat

ive

ata

ver

tica

lta

ng

ent.

lim

x→

af′

(x)

=∞

En

dp

oin

t

Afu

nct

ion

isn

ot

dif

fere

nti

able

atan

end

po

int

bec

ause

the

der

ivat

ive

can

on

lyb

eca

lcu

late

dfr

om

on

esi

de.

Ho

wev

er,

sin

cean

end

po

int

has

ao

ne-

sid

edd

eriv

ativ

e,th

een

dp

oin

tso

nth

eg

rap

ho

fth

ed

eriv

ativ

eo

fa

fun

ctio

nar

efi

lled

in.

En

dp

oin

tsar

ea

sou

rce

of

alo

to

fse

emin

gin

con

sist

ency

inca

lcu

lus.

Tri

go

no

me

tric

Fu

nc

tio

ns

Tri

go

no

me

tric

Ide

nti

tie

s

Tri

go

no

met

ric

iden

titi

es(p

age

42)

can

be

use

dto

sim

pli

fyex

pre

ssio

ns

bef

ore

or

afte

rfi

nd

ing

ad

eriv

a-ti

ve.

De

riva

tio

n

Sin

e,co

sin

e,ta

ng

ent,

cota

ng

ent,

seca

nt,

and

cose

can

tar

etr

igo

no

met

ric

fun

ctio

ns.

Eac

htr

igo

no

met

ric

fun

ctio

nh

asa

der

ivat

ive.

20

the

do

mai

nis

rest

rict

ed,

the

end

po

ints

of

the

do

mai

nm

ust

also

be

chec

ked

tose

eif

they

are

glo

bal

extr

ema.

cri

tic

al

po

int

po

int

ind

om

ain

off

wh

ere

f′=

0o

rf′

do

esn

ot

exis

t

Ex

trem

aca

no

nly

occ

ur

atcr

itic

alp

oin

tsan

den

dp

oin

ts.

Tru

eex

trem

are

qu

ire

asi

gn

chan

ge

inth

efi

rst

der

ivat

ive.

Th

ism

akes

sen

se—

the

gra

ph

mu

stri

se(p

osi

tiv

efi

rst

der

ivat

ive)

and

fall

(neg

ativ

efi

rst

der

ivat

ive)

tofo

rma

max

imu

m.

Inb

etw

een

risi

ng

and

fall

ing

,o

na

smo

oth

curv

e,th

ere

wil

lid

eall

yb

ea

po

int

of

zero

slo

pe

—th

em

axim

um

.A

min

i-m

um

wo

uld

exh

ibit

sim

ilar

pro

per

ties

,bu

tin

rev

erse

.

Fir

st

De

riva

tiv

eTe

st

Th

isle

ads

toa

sim

ple

met

ho

dto

clas

sify

ast

atio

nar

yp

oin

t—

plu

gx

val

ues

(tes

tp

oin

ts)

slig

htl

yle

ftan

dri

gh

tin

toth

ed

eriv

ativ

eo

fth

efu

nct

ion

.If

the

resu

lts

hav

eo

pp

osi

tesi

gn

sth

enit

isa

tru

eex

trem

um

.T

oca

lcu

late

the

coo

rdin

ates

of

the

min

imu

mo

rm

axim

um

po

int,

on

ew

ou

ldp

lug

the

det

erm

ined

xv

alu

ein

toth

eo

rig

inal

fun

ctio

nto

fin

dit

sy

val

ue.

•If

f′(x

)<

0fo

rx

<c

and

f′(x

)>

0fo

rx

>c,t

hen

f(c)

isa

loca

lm

inim

um

.

•If

f′(x

)>

0fo

rx

<c

and

f′(x

)<

0fo

rx

>c,t

hen

f(c)

isa

loca

lm

axim

um

.

Cau

tio

nm

ust

be

exer

cise

dw

ith

this

met

ho

d,

as,

ifa

po

int

too

far

fro

mth

eex

trem

um

isp

ick

ed,

on

eco

uld

tak

eit

on

the

far

sid

eo

fan

oth

erex

trem

um

and

inco

rrec

tly

clas

sify

the

po

int.

Am

ore

rig

oro

us

met

ho

dto

clas

sify

ast

atio

nar

yp

oin

tis

call

edth

eex

trem

um

test

that

use

sth

ese

con

dd

eriv

ativ

e,b

ut

this

sim

ple

met

ho

dis

acce

pta

ble

.

Se

co

nd

De

riva

tiv

eTe

st

•If

f′(c

)=

0an

df′′ (

c)

>0,t

hen

cis

alo

cal

min

imu

m.

•If

f′(c

)=

0an

df′′ (

c)

<0,t

hen

cis

alo

cal

max

imu

m.

No

teth

atth

ese

con

dd

eriv

ativ

ete

stca

nn

ot

be

use

dto

ver

ify

anex

trem

aif

the

firs

to

rse

con

dd

eriv

a-ti

ve

do

esn

ot

exis

t.

Info

rma

tio

n

Sta

tio

nar

yP

oin

tF

irst

Der

ivat

ive

Sec

on

dD

eriv

ativ

e

Min

imu

mP

oin

tze

roo

ru

nd

efin

edp

osi

tiv

eo

ru

nd

efin

ed

Max

imu

mP

oin

tze

roo

ru

nd

efin

edn

egat

ive

or

un

defi

ned

“Fla

tpo

int”

zero

zero

25

Tri

go

no

met

ric

Fu

nct

ion

Der

ivat

ive

sin

xco

sx

cosx

−si

nx

tan

xse

c2x

cotx

−cs

c2x

secx

secx×

tan

x

cscx

−cs

cx×

cotx

Sin

e

Th

ed

eriv

ativ

eo

fsi

ne

isco

sin

e.

d dx[s

in(x

)]=

cos(

x)

Co

sin

e

Th

ed

eriv

ativ

eo

fco

sin

eis

neg

ativ

esi

ne.

d dx[c

os(

x)]

=−

sin(x

)

Ta

ng

en

t

Usi

ng

the

qu

oti

ent

rule

(pag

e18

)an

dth

eP

yth

ago

rean

iden

tity

cos2

(x)+

sin

2(x

)=

1,

the

der

ivat

ive

of

tan

gen

tca

nb

ed

eriv

ed.

tan(x

)=

sin(x

)

cos(

x)

d dx[t

an(x

)]=

cos2

(x)+

sin

2(x

)

cos2

(x)

d dx[t

an(x

)]=

1

cos2

(x)

d dx[t

an(x

)]=

sec2

(x)

Th

eref

ore

,th

ed

eriv

ativ

eo

fta

ng

ent

isth

esq

uar

eo

fse

can

t.

d dx

tan(x

)=

sec2

(x)

21

Co

tan

ge

nt

Usi

ng

the

qu

oti

ent

rule

(pag

e18

)an

dth

eP

yth

ago

rean

iden

tity

cos2

(x)+

sin

2(x

)=

1,

the

der

ivat

ive

of

cota

ng

ent

can

be

der

ived

.

cot(

x)

=co

s(x)

sin(x

)

d dx[c

ot(

x)]

=−

sin

2(x

)−

cos2

(x)

sin

2(x

)

d dx[c

ot(

x)]

=−

1

sin

2(x

)

d dx[c

ot(

x)]

=−

csc2

(x)

Th

eref

ore

,th

ed

eriv

ativ

eo

fco

tan

gen

tis

the

neg

ativ

eo

fth

esq

uar

eo

fco

seca

nt.

d dx[c

ot(

x)]

=−

csc2

(x)

Se

ca

nt

Usi

ng

the

qu

oti

ent

rule

(pag

e18

),th

ed

eriv

ativ

eo

fse

can

tca

nb

ed

eriv

ed.

sec(

x)

=1

cos(

x)

d dx[s

ec(x

)]=

sin(x

)

cos2

(x)

d dx[s

ec(x

)]=

1

cos(

x)×

sin(x

)

cos(

x)

d dx[s

ec(x

)]=

sec(

x)×

tan(x

)

Th

eref

ore

,th

ed

eriv

ativ

eo

fse

can

tis

seca

nt

mu

ltip

lied

by

tan

gen

t.

d dx[s

ec(x

)]=

sec(

x)×

tan(x

)

Co

se

ca

nt

Usi

ng

the

qu

oti

ent

rule

(pag

e18

),th

ed

eriv

ativ

eo

fco

seca

nt

can

be

der

ived

.

22

csc(

x)

=1

−si

n(x

)

d dx[c

sc(x

)]=

−co

s(x)

sin

2(x

)

d dx[c

sc(x

)]=

−1

sin(x

cos(

x)

sin(x

)

d dx[c

sc(x

)]=

−cs

c(x)×

cot(

x)

Th

eref

ore

,th

ed

eriv

ativ

eo

fco

seca

nt

isth

en

egat

ive

of

cose

can

tm

ult

ipli

edb

yco

tan

gen

t.

d dx[c

sc(x

)]=

−cs

c(x)×

cot(

x)

Co

mb

inin

gw

ith

De

riva

tiv

eR

ule

s

Inm

ost

case

s,o

ne

mu

std

eter

min

eth

ed

eriv

ativ

eo

fan

anex

amp

leth

atre

qu

ires

the

use

of

der

ivat

ive

rule

sin

add

itio

nto

the

kn

ow

led

ge

of

the

der

ivat

ives

of

trig

on

om

etri

cfu

nct

ion

.O

ne

may

app

lyth

efo

rmtr

ig(a

)to

man

yex

amp

les,

wh

ere

trig

isth

etr

igo

no

met

ric

fun

ctio

nan

da

isth

ean

gle

.

Bas

edo

nth

ech

ain

rule

(pag

e17

),th

ed

eriv

ativ

eo

ftr

ig(a

)w

ou

ldb

e(

d dx[t

rig])

(a)×

d dx[a

].

d dx[t

rig

(a)]

=

(

d dx[t

rig](

a))

×d dx[a

],

wh

ere

d dx[t

rig]

isth

ed

eriv

ativ

eo

fth

etr

igo

no

met

ric

fun

ctio

n,a

nd

d dx[a

]is

the

der

ivat

ive

of

the

ang

le.

Ex

am

ple

:si

n(2

x)

d dx[s

in(2

x)]

=

(

d dx

[ sin

] (2x))

×d dx[2

x]

d dx[s

in(2

x)]

=(c

os(

2x))×

2

d dx[s

in(2

x)]

=2

cos(

2x)

As

ym

pto

tes

Ali

nea

ras

ym

pto

teis

ast

raig

ht

lin

eth

ata

gra

ph

app

roac

hes

,b

ut

do

esn

ot

bec

om

eid

enti

cal

to.

Asy

mp

tote

sar

efo

rmal

lyd

efin

edu

sin

gli

mit

s.S

eeth

eth

eas

ym

pto

tes

sect

ion

of

the

lim

its

chap

ter

on

pag

e7

for

mo

rein

form

atio

n.

23