1. The problem statement, all variables and given/known data (a) Find the intervals on which f is increasing or decreasing. (b) Find the local maximum and minimum values of f. (c) Find the intervals of concavity and the inflection points. x2/(x2+3) 2. Relevant equations 3. The attempt at a solution a) I find that f'(x)=6x/(x2+3)2 I am stuck because (x2+3)2 has no solutions and I don't know how to define x in order to proceed further. If anybody can help me out understanding this, I will be very thankful.