Answer
As the value of n increases, the number of loops of $\cos n\theta $ increases. If n is odd, there are n loops and $\theta \,\max \,=\,\pi $ traces the graph once, while if n is even, there are 2n loops and $\theta \,\max \,=\,2\pi $ traces the graph once. Yes, the conclusions are the same as for $\sin \,n\theta $.
Work Step by Step
From the graphs, it can be observed that the number of loops of $\cos n\theta $ increases with increase in the value of n. If n is odd, there are n loops and $\theta \,\max \,=\,\pi $ traces the graph once, while if n is even, there are 2n loops and $\theta \,\max \,=\,2\pi $ traces the graph once.
Yes, the conclusions are the same as for $\sin \,n\theta $.
