02-18-2008
Sorry that this is mad old, but I don't visit this forum too often.
Basically, this problem becomes really simple if you just use what's called the double angle identity, or more simply, the reduction identity.
You can use the identity cos(x)^2= 1/2(1-cos(2x))
So, I'm fairly certain you can integrate 1/2 - 1/2cos(2x) as it would be --->
1/2x + 1/4sin(2x) |