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 Author Comment/Response John Barber 02/20/03 12:16pm Hi Folks: When I give Mathematica (4.1) the following: Integrate[(x^2) (1 - Exp[-1/x^12]), {x, 0, Infinity}] it claims the value of the integral is Infinity. I know this to be false, both from the physical context of the problem, and from the fact that a quick glance at a graph of the function shows that it is indeed integrable. A numerical integration of the function: NIntegrate[(x^2) (1 - Exp[-1/x^12]), {x, 0, Infinity}] yields 0.408472. Furthermore, after a change of variables x -> 1/z, we have the following as an equivalent expression for the top integral: Integrate[(1/z^4)(1-Exp[-z^12]),{z,0,Infinity}] for which mathematica gives a finite, positive answer: -(1/12)Gamma[-1/4] = 0.408472 Why the does Mathematica assert, wrongly, that the first form of the integral is divergent? Thanks! URL: ,

 Subject (listing for 'Inconsistent results for strange integral') Author Date Posted Inconsistent results for strange integral John Barber 02/20/03 12:16pm Re: Inconsistent results for strange integral Forum Modera... 02/23/03 1:29pm Re: Inconsistent results for strange integral John Barber 02/24/03 09:01am
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