How to evaluate this definite integral?? \[ \frac{64}{\pi^3} \int_0^\infty \frac{ (\ln x)^2 (15-2x)}{(x^4+1)(x^2+1)}\ dx \] http://www.wolframalpha.com/input/?i=64%2Fpi^3+*+integrate+from+0+to+infinity+%28ln+x%29^2+%2815-2x%29%2F%28%28x^4%2B1%29%28x^2%2B1%29%29
\[ \frac{64}{\pi^3} \int_0^\infty \frac{ (\ln x)^2 (15-2x)}{(x^4+1)(x^2+1)}\ dx \]
Try integration by parts
maybe .. but very difficult for me.
do you not know how to do integration by parts?
no sorry ... could you help me please??
Nvm integration by parts wouldn't work to my knowledge I think you are going to need someone with a greater understanding of integrals to help you @satellite73 @KingGeorge
thank you :)
one method is letting \(\ln x=t\) and representing integrand by series... @experimentX come here my friend
huh?
we need something that converges between 0 and infinity http://www.wolframalpha.com/input/?i=expand+%28ln+x%29^2+%2815-2x%29%2F%28%28x^4%2B1%29%28x^2%2B1%29%29+at+x%3D1
need something like |dw:1345610604780:dw| ... let's see what series has closed value of pi^3
the original question was posted here http://math.stackexchange.com/questions/168485/help-find-hard-integrals-that-evaluate-to-59/168509#168509
|dw:1345610982159:dw|
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