# Need help on integrals plez

1. Sep 15, 2008

### DarrenLockyer

Hey i was wondering if any one knew how to do:
The integral of : x^4*tan^-1 dx???????????

Im rater stuck on how to do it. plez help

2. Sep 15, 2008

### HallsofIvy

Staff Emeritus
How can you say you are stuck and not show any work at all? If you are stuck then you must have tried something! What have you tried and why didn't it work.

Have you tried integration by parts at all?

Normally, when I see a power of x times another function, say $\int x^n f(x)dx$ I think of u= xn, dv= f(x)dx so that integration by parts will reduce the power of x. Here, however, tan-1(x) looks difficult to integrate so try the other way around. If u= tan-1(x) and dv= x4dx, what do you get?