Re: Integration Methods in PARI

[Henri.Cohen@math.u-bordeaux.fr]

Quoting kevin lucas <lucaskevin296@gmail.com>:

> I have been trying to evaluate the following integral in PARI:
>
> intnum(x=0, +oo, x*exp(cos(x))*sin(sin(x))/(x^2-1))
As Bill says, the error is due to the fact that your integral diverges at
x=1. But even once this is repaired, Pari is unable to integrate an
oscillating function of this type; in fact I would be surprised if
any software could do it. And Bill's suggestion of finding the Fourier
expansion will very probably not work.