Use the power reducing formulas to rewrite cot^24xsin^44x in terms of the first power of cosine.
I'm going to assume this is
cot^2(4x)sin^2(4x) ....if so....
[ cos^2 (4x) / sin^2(4x)] * sin^2 (4x) =
cos^2 (4x)
Using the reduction formula :
cos^2(θ) = [ 1 + cos (2θ) ] / 2 we have
cos^2 (4x) =
[ 1 + cos (8x) ] / 2 =
1 / 2 + cos(8x) / 2