1. The problem statement, all variables and given/known data Find the second derivative of 4x^2 + 3x - 9y^2. Answer in terms of y. 2. Relevant equations All derivative formulas. 3. The attempt at a solution [PLAIN]http://http://i52.tinypic.com/2w2ptex.jpg [Broken] I can't get much further than this; the thing that gets me is how to put everything in terms of y. Help? Thanks!