Let's review the Warm-Up Exercise and see how the first derivative indicates where a graph of a function is increasing or decreasing and where it has either a relative minimum or maximum. Pretty much the entire lesson is contained in this one problem. Duration: 3:46

In this video, we formally define where a function is increasing or decreasing in an algebraic sense. Notice the complete lack of calculus. Duration: 6:58

Print a copy of the Investigation below, if you have the means. Use this document to investigate the link between the first derivative and the intervals over which a function is increasing or decreasing.