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**alternat****Member**- Registered: 2006-04-05
- Posts: 1

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!

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**George,Y****Member**- Registered: 2006-03-12
- Posts: 1,333

difficult, lol

*Last edited by George,Y (2006-04-05 14:34:18)*

**X'(y-Xβ)=0**

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**George,Y****Member**- Registered: 2006-03-12
- Posts: 1,333

is a hyperfunction, which cannot have an explicit expression

*Last edited by George,Y (2006-04-05 22:40:47)*

**X'(y-Xβ)=0**

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