APCALCULUS
Derivative
ADERIVATIVEFUNCTION1Thederivativefu
ctio
orsimplythederivativeisdefi
edas
fx=y=limylimfxxfx
xx0
x0
x
2Fi
dthederivativefu
ctio
aFi
dy
bFi
dtheaveragerateofcha
geyx
cFi
dthelimitlimyxx0
3Geometricsig
ifica
ce
Co
siderage
eralfu
ctio
yfxafixedpoi
tAafaa
davariablepoi
t
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xa
NowasBAxaa
dtheslopeofchordABslopeofta
ge
tatA
So
fxfa
limxa
xa
is
fa
Thusweca
k
owthederivativeatxa
istheslopeoftheta
ge
tatxa
4Rules
fxCaco
sta
t
x
si
xcosx
ta
x
arcsi
x
fx0
x
1
cosxsi
x
sec2x1cos2x
11x2
1
fAPCALCULUS
l
x
logxaexax
uxvxuxvx
uxvx
Derivative
1x1logexaex
axl
a
uxvx
uxvxuxvx
uvuvv2
v0
5Thechai
rule
Ifyfuwhereuuxthe
dydydudxdudx
fxegxfxegxgx
fxl
gxfxgxgx
fxuxeevx
l
uxvx
vxl
ux
fxevxl
uxvxl
uxvxuxux
6I
versefu
ctio
Parametricfu
ctio
a
dImplicitfu
ctio
I
versefu
ctio
dy1fx1
dxdxdy
f1x
ieyarcsi
xxsi
y
2
fAPCALCULUS
Derivative
dy
Parametricfu
ctio
dy
dt
dxdxdt
ieytxt→t1xy1x
dydydtdydttdxdtdxdxdtt
Implicitfu
ctio
Fxyx0Fxfx0
xacost
x2y2a20
t02
yasi
t
yxdyacostcottdxasi
t
7Highderivative
fxd2ylimfxxfx
dx2
x0
x
yxyxdydydtcsc2t1xdxdxdtasi
tasi
3t
f
xlimf
1xxfx
1
x0
x
ysi
xycosxsi
xycosxsi
x2
2
2
2
y
si
x
2
BAPPLICATIONSOFDIFFERENTIALCALCULUS
1Mo
oto
icity
aIfSisa
i
tervalofreal
umbersa
dfxisdefi
edforallxi
Sthe
:
3
fAPCALCULUS
Derivative
fxisi
creasi
go
Sfx0forallxi
Sa
dfxisdecreasi
go
Sfx0forallxi
S
bFi
dthemo
oto
ei
tervalFi
ddomai
ofthefu
ctio
Fi
dfxa
dxwhichmakefx0
Drawsig
diagramfi
dthemo
oto
ei
terval2MaximaMi
imaHorizo
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flectio
Statio
arypoi
t
CINTEGRAL
1Theideaofdefi
itei
tegral
Wedefi
etheu
ique
umberbetwee
alllowera
duppersumsas
b
a
f
xdx
a
dcallit“thedefi
itei
tegralof
fxfromatob”
4
fAPCALCULUS
Derivative
ie
1
f
xi
x
b
a
f
xdx
f
xxi
i0
i1
where
xba
We
otethatas
1
f
xxi
b
a
f
xdx
a
d
i0
f
xxi
b
a
f
xdx
i1
Wewrite
lim
i1
f
xxi
b
a
f
xdx
Iffx0forallxo
abthe
b
a
f
xdx
istheshadedarea
2Propertiesofdefi
itei
tegrals
b
a
f
xdx
ba
f
xdx
b
a
cf
xdx
r