Order the first derivative test

Exercise and reference answers

Steps

1. Find the critical points where f ′(x) = 0 or f is not differentiable
2. Check f is continuous at the critical point c
3. Look at the sign of f ′(x) just to the left of c
4. Look at the sign of f ′(x) just to the right of c
5. Read the verdict from whether that sign changed, and how

Explanation