1. The problem statement, all variables and given/known data Find f ' (x) if f(x) = 4x + 4 / x2 + 4 2. Relevant equations I used the mnemonic "lo dhi - hidlo / (lo)^2 3. The attempt at a solution I got -4x^2 +16-8x / (x^2+4)^2 but it's telling me I'm wrong? Why? I computed it again but I still got the same answer.