math
posted by Jessica on .
Generalize this to fine a formula for the integral:
sin(ax)cos(bx)dx
Could someone tell me what they got for an answer so I can check it to see if my answer is right.
My answer:
1/2sinasinbx^21/3acosaxcosbx^3+ integral 1/3 a^2cosbx^3sinax..I'm not sure hot to find the integral of the last part.

I thnink the "generalizing" formula they expect you to use is the identity:
sin(ax) cos(by) = (1/2)[sin((a+b)x) + sin ((ab)x)]
Those two terms can be easily integrated separately and added.