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Topic: integration question: 1/(Sqrt[1 - x^2])*Exp[-(1 - x)^2]
Replies: 4   Last Post: Aug 5, 2013 5:51 PM

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 Nasser Abbasi Posts: 6,677 Registered: 2/7/05
Re: integration question: 1/(Sqrt[1 - x^2])*Exp[-(1 - x)^2]
Posted: Aug 5, 2013 4:26 PM

On 8/5/2013 3:11 PM, Axel Vogt wrote:
> On 05.08.2013 21:58, Nasser M. Abbasi wrote:
>> 1/(Sqrt[1 - x^2])*Exp[-(1 - x)^2]
>
> Plot from 0 ... 1 and its imaginary part from 1 ... 4
> to understand the the problem
>

Oh, a pole at x=1 ofcourse.

This explains why numerical integration worked
(but lots of screaming from Mathematica along the way)

NIntegrate[1/(Sqrt[1 - x^2])*Exp[-(1 - x)^2], {x, 0, Infinity}]

1.29331348557849 - 1.19124235143936 I

same with Maple's

int(1/(sqrt(1 - x^2 ))*exp((- (1 - x)^2)),x=-0..infinity,numeric=true);
1.29721962103293 - 1.19514845220774 I

Ok. Sorry, I just overlooked this.

thanks,
--Nasser

Date Subject Author
8/5/13 Nasser Abbasi
8/5/13 Axel Vogt
8/5/13 Nasser Abbasi
8/5/13 Nasser Abbasi
8/5/13 clicliclic@freenet.de