1. The problem statement, all variables and given/known data Deriving http://www4d.wolframalpha.com/Calculate/MSP/MSP20181a00e6i82g005gag00005gb4c7hic8g2i3hi?MSPStoreType=image/gif&s=57&w=79&h=43 [Broken] 2. Relevant equations 3. The attempt at a solution My attempt gives me: -48/(x^2-16)^2 + 192x^2/(x^2-16)^3 via product rule Wolfram alpha gives me this for an answer http://www4d.wolframalpha.com/Calculate/MSP/MSP40371a00e53i06h6352d000061574g9ehi6a9958?MSPStoreType=image/gif&s=15&w=224&h=48 [Broken] I can't seem to figure out how to match my answer with Wolfram, even though it's not a tough derivative. Am I maybe not simplifying enough?