1. The problem statement, all variables and given/known data Differentiate (-sqrt(1 + x^2)) / x 2. Relevant equations [f'(x)g(x) - f(g)g'(x)] / [g(x)]^2 3. The attempt at a solution I need to simplify it further, but before I do I checked it into Mathematica and it says the derivative is incorrect. What did I do wrong?