First Derivative Test
First derivative test is when f’ changes from negative to positive at x = a or positive to negative (has a minimum or maximum)
If f has a local minimum at x=a on domain
Second Derivative Test
If f’(a) = 0 and f”(a) > 0 then f has a Minimum
If f’(a) = 0 and f”(a) < 0 then f has a Maximum
If f has a local minimum at x=a on the domain