1. The problem statement, all variables and given/known data Sin(tan(2x)) With respect to x 2. Relevant equations Differentiation 3. The attempt at a solution My question is whether I can simply use d/dx (Tan x) = Sec^2(X) to extrapolate that to d/dx(tan 2x) = Sec^2(2x) ? Or do I have to convert to sine/cosine and go from there?