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## #1 2006-04-06 02:19:01

alternat
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### Complicated integration

I need to integrate this;

fX (x) = e^xt [e^((x−a)/b)]/b[1 + e^((x−a)/b)]^2, for − ∞ < x < ∞,
where the parameters a and b satisfy −∞ < a < ∞ and b > 0

in order to get a function in terms of t.

If it makes things easier, [e^((x−a)/b)]/b[1 + e^((x−a)/b)]^2 integrates to -1/(e^(x-a/b))+1. I tried integration by parts, and then tried to integrate the second part of the answer, but everything cancelled out...sigh. Help me out, guys!

## #2 2006-04-06 12:01:38

George,Y
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### Re: Complicated integration

difficult, lol

Last edited by George,Y (2006-04-06 12:34:18)

X'(y-Xβ)=0

## #3 2006-04-06 14:18:40

George,Y
Super Member

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### Re: Complicated integration

is a hyperfunction, which cannot have an explicit expression

Last edited by George,Y (2006-04-06 20:40:47)

X'(y-Xβ)=0