Originally Posted by

**kdogg121** I am stuck on this problem, and I am thinking that I am not getting the derivatives (1st and 2nd) correct. Here is the problem:

F(X)= 2X(X+4)^3

I know I have to get the first and second deriviative's but don't I need to cube the inside function first and then distribute the 2x to it? Or does the power rule come into effect here? I have tried cubbing the inside terms and then distributing the 2x but it doesn't seem to give me the correct zeros's of the graph so if someone could illustrate. Please Help, Thanks.