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Re: Compute integral
Posted:
May 2, 2014 2:38 AM


In article <7a15bcf9f4b546a188cf438a1434929b@googlegroups.com>, <cootercrew@gmail.com> wrote:
> Compute the integral from 0 to 1 of ln(1+x)/(1+x^2)dx. Hint: Use the > substitution y+1=2/(x+1)
Just to be sure: do you mean
ln(1+x)  1+x^2
Or
ln( (1+x)/(1+x^2) )?
The first one does not seem to evaluate to closed form, the second one is standard: write as ln(1+x)  ln(1+x^2) and do them by parts, using the trick int(f) = x*f  int(x*f'). Works here since the f' terms have no "ln" in them and in both case x*f' is trivial to integrate.
Cheers, L.



