If you shift the graph of $\displaystyle{y}={\cos{\theta}}\usepackage{cmbright}\Huge\$ by $\displaystyle\frac{{{3}\pi}}{{2}}\usepackage{cmbright}\Huge\$ units to the left, this will result in a repeating valley and hill pattern, with a hill just to the right of the y-axis, and a valley just to the left. This matches the given graph.