Answer
Between 0$^{\circ}$ and 360$^{\circ}$ $\cos$ $\theta$ = -$\sin$ $\theta$ is true for 135$^{\circ}$ and 315$^{\circ}$
Work Step by Step
$\theta$ = 135$^{\circ}$
$\cos$ 135$^{\circ}$ = -$\frac{\sqrt2}{2}$
$\theta$ = 315$^{\circ}$
$\sin$ 315$^{\circ}$ = $\frac{\sqrt2}{2}$
Therefore:
-$\sin$ 315$^{\circ}$ = -$\frac{\sqrt2}{2}$
Therefore, $\cos$ 135$^{\circ}$ = -$\sin$ 315$^{\circ}$
Therefore:
Between 0$^{\circ}$ and 360$^{\circ}$ $\cos$ $\theta$ = -$\sin$ $\theta$ is true for 135$^{\circ}$ and 315$^{\circ}$
