1. The problem statement, all variables and given/known data Find the volume of the solid enclosed by the cylinders z=x^2, y=x^2, and the planes z=0 and y=4. 2. Relevant equations 3. The attempt at a solution ∫∫ x^2 dA For the limits of integration, I obtained y=x^2 and y=4, x=0 and x=2 I changed the order of integration and obtained x=y^(1/2) and x=0, y=0 and y=4. ∫0 to 4 ∫0 to y^(1/2) x^2 dxdy (1/3) * ∫0 to 4 (y^(3/2)) dy 1/3*[(2/5)(4)^(5/2)] = 64/15 I am not sure where I am going wrong. The back of the book says it's 128/15 though. In fact, for a few problems I've got (1/2)*the correct answer for these problems.