I need to integrate this integral from -infinity to infinity,

∫▒〖(x^3 e^x)/(e^x+1)^2 dx〗

The question says I can look it up in integral table but I cannot find tables with this type of integral in it.

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- Dec 12th 2009, 05:54 PMthealbinointegral tables
I need to integrate this integral from -infinity to infinity,

∫▒〖(x^3 e^x)/(e^x+1)^2 dx〗

The question says I can look it up in integral table but I cannot find tables with this type of integral in it. - Dec 12th 2009, 07:38 PMsimplependulum
note that it is an odd function ( a fantastic odd function (Evilgrin) )

- Dec 12th 2009, 08:28 PMthealbino
So it cancels out to 0?

If that is the case then I need to integrate (x^4*e^x)/((e^x+1)^2).

I am doing a sommerfield expansion and I need another term to survive. - Dec 12th 2009, 08:58 PMsimplependulum

when

- Dec 12th 2009, 09:08 PMthealbino
Perfect. Thank You.

- Dec 13th 2009, 04:22 AMmr fantastic
- Dec 14th 2009, 01:47 AMsimplependulum