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Re: Integration of Exp[-x^2]/(1 + Exp[a * x])


Hi,

if Exp[a*x] < 1 you can try a geometric series, i.e.,

1/(1+Exp[a*x})= Sum[(-Exp[a*x])^n,{n,0,Infinity}]

and integrate

term=Integrate[Exp[-x^2]*(-Exp[a*x])^n, x]

and work with

Sum[Evaluate[term], {n, 0, Infinity}]

for a<0 the sum should be quickly convergent.

Regards
  Jens

Stefan wrote:
> 
> Hello,
> 
> I have to integrate the function Exp[-x^2]/(1 + Exp[a * x]) where a is
> real-valued parameter. Unfortunately
> 
> Integrate[Exp[-x^2]/(1 + Exp[a * x]), x]
> 
> yields no results. Does anyone know a clever trick I might have missed? Any
> hint would be welcome,
> 
> Thanks in advance, Stefan


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