of infinite types siexdx -3 ¥eemmmmpeople.math.umass.edu/~johnston/m128f18/128f18-10-1.pdf ·...

6
Improper Integrals -3 types A INFINITE interval of integration siexdx ¥eEmmmm Ex 2) fix become INFINITE on the interval so ax ' ¥€÷e , 3) Both situations hold s ! # dx

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Improper Integrals

-3types A INFINITE interval of integration

siexdx ¥eEmmmm⇐ Ex

2) fix become INFINITE onthe interval

soax

'

¥€÷e,3) Both situations hold

s! # dx t¥

Et .

fod×=SoEdk%

. .fexdx - - Etc

*

=- Elo Efendi! '¥9

,¥7 '

= .

-

Lexi .

".

"

g

= - [ e-"

-"

-e-

o]=

- [ o - T!e→"=iinex=oT=

x - soA FINITE # and

fine'=fi;s¥=o we say the integralConRG

Ee. S! 'T dx O'

tix :t¥±a:Exit: "

× .

= In I - In"

o

' '= O - In

"

o

"

=o - C - a ) =

In"

o

' '

=L In X = - 0 Not afinite # so

we say that the

integral

Ii;nohx=- d

DIUERGfind In x

-- a -

exi.si#dx--i8x-adxsxIIitItI

'

t÷= I

"

= - I'

Ii.

"

÷=¥÷=±= - [ x' Ii

."

] x' - I

= - [ ¥.

-¥3'x'

tx=o= - [ o - D= ⑤

in Finite # sothe Mtesrd/Con1uER6EJ

.

Integration By Parts .

-

-

. Sudu=uv-Sudu#where

does the formula come from ?

Pffudygti ¥ [ fang 3 = fang 'm t gunfix )

⇒ fixigcx, = f¥x[fungus]dx=ffixdxt fgcxiffxidx

solve for this term

{ fang 's dx =fix gcxl - f gcxiftxidx

TE IT THE

u -

- fan "

gudu=uV-Sv#fda -

-f 'M DX

=

"

known"

-

"

Easier"

Island .¥to

EI : f×e2×d× fudu=uu - Suda

2K

see :=¥s:¥ .da=Idx du --e'

''

dx

choose U so that= e

"- tzfedx

d# is simpler than=z×eH - taffeta )

UM =z×eH_tyeHt#