Answer
$\cos$ 30$^{\circ}$ = $\frac{-\sqrt3}{2}$
$\sec$ 30$^{\circ}$ = -$\frac{2\sqrt3}{3}$
Work Step by Step
We use the reference angle to determine the trigonometric functions.
$\theta$$^{1}$ = 210$^{\circ}$ - 180$^{\circ}$
$\theta$$^{1}$ = 30$^{\circ}$
$\cos$ 30$^{\circ}$ = $\frac{-\sqrt3}{2}$
$\sec$ 30$^{\circ}$ = $\frac{2}{-\sqrt3}$ = -$\frac{2\sqrt3}{3}$
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