Hello! In need of help yet again. I've seemed have gotten stumped :|

$\displaystyle sin(3x)+sin(x) = 2sin(2x)cos(x)$

Took the left side and changed it to:

$\displaystyle sin(2x+x)+sin(x)$

From there I got it equaled to:

$\displaystyle sin(2x)cos(x)+cos(2x)sin(x)+sin(x)$

from then on I get confused. I tried using the double angle formulas to expand the sin(2x) and the cos(2x) but that gets me no where. Any ideas on what I could do next?