1. The problem statement, all variables and given/known data Show that f(x) = x^4 + 4x + c = 0 has at most 2 roots. 2. Relevant equations 3. The attempt at a solution I'm not really sure how to approach this problem, I think I have to use the IMVT / Rolle's Theorem / MVT. Any help to even get me started would be greatly appreciated!