Ok the original problem is

Integral sin^(4) x cos^(4) x

After making the two of those sin^2 and and cos^2 and doing trig function substation my integral became

1/4 integral [1-cos^2 2x]^2

Then 1/4 [sin^2 2x]^2

I am officially I stuck and I know I'm close to solving it but I am now waving the white flag

Please help!