Math Help - [SOLVED] Help on integrating

1. [SOLVED] Help on integrating

I recognize that it is in the arctan x form but i dont know what to do with it, the numerator throws me off .

X^3/ (x^2+1) dx

I cant figure out how to change it or get rid of the x^3

2. Originally Posted by aervid
I recognize that it is in the arctan x form but i dont know what to do with it, the numerator throws me off .

X^3/ (x^2+1) dx

I cant figure out how to change it or get rid of the x^3
Have you tried the sub. $u = x^2 + 1$?

Just a little note..You may not need to use arctan(x) for every time you encounter $x^2 + 1$.

3. I got it! thanks.

Our teacher has been harping on us about arctan, arcsin, and acr sec x lately so that was what first jumped to my head. Ill keep that in mind.