Whitman College: David Guichard's "Calculus, Chapter 5: Curve Sketching, Section 5.1: Maxima and Minima"

Read Section 5.1 (pages 103-106). Fermat's Theorem indicates how derivatives can be used to find where a function attains its highest or lowest points.

Click https://s3.amazonaws.com/saylordotorg-resources/wwwresources/site/wp-content/uploads/2012/07/calculus_05_Curve_Sketching.pdf link to open resource.