[tex]\[\begin{array}{l}\frac{\pi }{4}rad = \frac{{360}}{{2\pi }} = \frac{{360}}{8} = 45^\circ \\\\\\ - \frac{{3\pi }}{4}rad = - \frac{{360}}{{2\pi }} = - \frac{{1080}}{8} = - 135^\circ \\\\\\\frac{{3\pi }}{2}rad = \frac{{360}}{{2\pi }} = \frac{{1080}}{4} = 270^\circ \\\\\\ - \frac{\pi }{2}rad = - \frac{{360}}{{2\pi }} = - \frac{{360}}{4} = - 90^\circ \end{array}\][/tex]