Answer
(a) $\sin{\frac{\pi}{2}} = 1$
(b) $\cos{\frac{\pi}{2}}=0$
(c) $\tan{\frac{\pi}{2}} \text{ is undefined}$
Work Step by Step
RECALL:
In a unit circle,
$\sin{s} = y
\\\cos{s} = x
\\\tan{s} =\frac{y}{x}$
The angle $\frac{\pi}{2}$ intersects the unit circle at the point $(0, 1)$.
Thus,
(a) $\sin{\frac{\pi}{2}} = 1$
(b) $\cos{\frac{\pi}{2}}=0$
(c) $\tan{\frac{\pi}{2}} = \frac{1}{0}, \text{ is undefined}$
