1. Aug 2, 2010

biogoal123

hey guys im absolutely stumped on this one integration problem:

it asks us to integrate sin (2x) e ^ (sin x)

i integrated by parts once and was left with an even larger term to integrate, which leads me to believe that i might be doing it wrong

any help is appreciated, thanks

2. Aug 2, 2010

Whitishcube

Try expanding sin(2x) using a double angle formula.

3. Aug 2, 2010

biogoal123

wow ok i feel like an idiot. when i split it into double angles i had (2 sin cos e^sin) and i kept having my two terms for integration by parts being (cos sin) and (e ^ sin) instead of the VERY OBVIOUS one which i kept missing which was (sin) and (cos e ^sin) which gave a very nice and smooth integration

thanks again

4. Aug 2, 2010