If A = \(\left[\begin{array}{cc} \cos \theta & \sin \theta \\ -\sin \theta & \cos \theta \end{array}\right]\) then A3 =
1
\(\left[\begin{array}{cc} \cos 3 \theta & \sin 3 \theta \\ -\cos 3 \theta & \sin 3 \theta \end{array}\right]\)
2
\(\left[\begin{array}{cc} -\cos 3 \theta & \sin 3 \theta \\ \sin 3 \theta & \cos 3 \theta \end{array}\right]\)
3
\(\left[\begin{array}{cc} \cos 3 \theta & \sin 3 \theta \\ -\sin 3 \theta & \cos 3 \theta \end{array}\right]\)
4
\(\left[\begin{array}{cc} \cos 3 \theta & -\sin 3 \theta \\ -\sin 3 \theta & \cos 3 \theta \end{array}\right]\)