Special Trig Values: Multiples of π/2

Trig values for multiples of $\frac{\pi}{2}$ are easy to remember. To remember them, draw a unit circle:

From this, it is very easy to see how to figure out the trig values. Since cosine is the x-coordinate and sine is the y-coordinate, just take each coordinate and figure out the corresponding coordinate.

$\sin{0} = 0 \text{ and } \cos{0} = 1$

$\sin{\frac{\pi}{2}} = 1 \text{ and } \cos{\frac{\pi}{2}} = 0$

And so on.