The graph of \(r = \cos 3 \theta\) is shown below.
If we plot the graph of \(r = \cos 3 \theta\) for \(0 \le \theta \le M\), then what is the smallest value of M that still produces the entire graph of \(r = \cos 3 \theta\)?
We need the radius to come back to the origin. The smallest M that makes r = 0 is 2*pi/3.
