1. The problem statement, all variables and given/known data Find the differential 2. Relevant equations Chain rule : dy/du=dy/du*du/dx Product rule: f(x)g'(x) + g(x)f'(x) 3. The attempt at a solution I have tried to move the radical to the top of the equation by making it into an exponent (x^2+1)^-1/2. I then used the product rule and the chain ruleIand i got lost somewhere simplifying it beyond that.