CPM Homework Help : CCA2 Problem 12-17

Using a graph of $f(x) =$ cos( $x$ ) for reference, graph $f(x) =|$ cos( $x$ ) $|$ .

Hint:

How does the absolute value change a value?
How would this change look on a graph?

Answer:

Repeating curve, moving from high to low points. High points are normal wave vertices, but low points are sharp turns, like connected sides of parabolas. First visible high & low points: (negative pi, comma 1), & (negative pi halves, coma 0), continuing in that pattern just past 3 pi halves.