# Minor help with integrals

• Jun 3rd 2010, 10:46 AM
abel2
Minor help with integrals
Needing to evaluate the integral:

sin(2x)/(47+(cos(x))^2)dx

This question might belong somewhere else but.. It's been a while since I've taken trig and is (cos(x))^2 the same as cos^2(x) or 2cos(x) or something entirely different?
• Jun 3rd 2010, 10:52 AM
General
Rewrite $sin(2x)$ as $2sin(x)cos(x)$

then substitute $u=cos^2(x)$ ..
• Jun 3rd 2010, 11:01 AM
abel2
ahh, thanks. I'm not good with trig identities.