Determine the extrema using the end points of a closed interval

The video tutorial covers the process of finding the derivative of a function, identifying critical numbers, and determining the absolute maximum and minimum values on a closed interval. It emphasizes the importance of checking endpoints when no critical numbers are present and reviews the concept of critical numbers in calculus.

What are the results of evaluating the function at the endpoints of the interval?

Explain the significance of checking critical numbers in calculus.