Proving the Integral Formula for Powers of Sine for the Perplexed

[r4sph4sp]

I need help with a question and I'm totally stuck at this! My friends can't help me so you are my last way out!

Prove

∫sin^n x dx= -(1/n)cos x sin^n-1 x + ((n-1)/n) ∫sin^n-2 x dx

Thanks for your time!

Sincerely :)

 

[micromass]

I see a product: \sin(x)\sin^{n-1}(x). Try partial integration on that...