Help with Indefinite integrals.

[master1425]

Homework Statement

$$\int sinx/(1+cos^{2}x)dx$$


Can anyone help me with this problem?

 

[Dick]

Did you try substituting u=cos(x) as a first step??

 

[master1425]

Ah ok, that was my biggest problem. I tried substituting u=1+cos^2x and u=sinx. But neither yielded the result I wanted.

So I will try using just u=cosx and see how that works for me.

 

[master1425]

Ok, I got that one finally.

How about this one?

$$\int x^{2}sinx/1+x^{6} dx$$

I tried u=sinx, but got stuck. Is that what I need to use? Any help would be appreciated.