$\begin{pmatrix} \cos(60^\circ) & -\sin(60^\circ) \\ \sin(60^\circ) & \cos(60^\circ) \end{pmatrix}$

$\begin{pmatrix} \cos(120^\circ) & -\sin(120^\circ) \\ \sin(120^\circ) & \cos(120^\circ) \end{pmatrix}$

$\begin{pmatrix} \cos(240^\circ) & -\sin(240^\circ) \\ \sin(240^\circ) & \cos(240^\circ) \end{pmatrix}$

$\begin{pmatrix} \cos(300^\circ) & -\sin(300^\circ) \\ \sin(300^\circ) & \cos(300^\circ) \end{pmatrix}$