What is the integral of (cos(x))^2?
cos(2x) = 2cos2(x)-1 by the double angle formula.
Rearrange to give cos2(x) = (cos(2x)+1)/2
Integrating this gives sin(2x)/4 + 1/4x + c
MC
cos(2x) = 2cos2(x)-1 by the double angle formula.
Rearrange to give cos2(x) = (cos(2x)+1)/2
Integrating this gives sin(2x)/4 + 1/4x + c
