1. The problem statement, all variables and given/known data (tan2x) - (sin2x) = (tan2x)(sin2x) Prove these two are equal. 2. Relevant equations Various trig identities, mainly tan2x = sin2x / cos2x 3. The attempt at a solution I tried putting in Sin2x / cos2x for tan, but I don't know where to go from there. Anyone mind helping me out?