3. The attempt at a solution
Thanks in advance for your help...
What did you try?
Did you try integration by parts, substitution?
I managed to get it by using substitution and then parts. Try making u=1/(1+x^2) and then when you get du, use u=1/(1+x^2) to solve for x to replace x with u. After that, use parts. Hope that helps I can give a more detailed answer if you still are having trouble.
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