1. The problem statement, all variables and given/known data Derivative of Sin22x 2. Relevant equations dy/dx = dy/du * du/dx y=U2 3. The attempt at a solution Just want to make sure I am doing this right*. Do I let U = Sin2x or U = 2x? Let's say U = Sin2x y=U2 then y` = 2Sin2x * cos2x? Or if U = 2x. y = SinU2 y` = 2cos2x * 2 y` = 4cos2x am i on the right track with either of these? any help is appreciated! thanks!