Integration using substitution

[SticksandStones]

[SOLVED] Integration using substitution

Problem: Find the integral of:
\int\sin^{6}\theta\cos\theta d\theta

My attempt:

Let u\equiv\cos\theta
so: du\equiv\sin\thetad\theta

Only I don't know where to go from there.

The book says it should \frac{1}{7}\sin^{7}\theta+C but I have no idea how they got that.

I'm probably missing something obvious here.

 

[Office_Shredder]

Try letting u=sin \theta

 

[Dick]

Your are much better off letting u=sin(x).

 

[SticksandStones]

Your are much better off letting u=sin(x).

Ah, that was the totally obvious thing I was missing. For some reason, I decided that the derivative of Sin(x) was...Sin(x)...

Thanks guys.