# Spinning Out Sine and Cosine

Spinning Out Sine and Cosine

Imagine a point that starts at and rotates counterclockwise on the unit circle. If is the length (in radians) of the arc on the circle between and the point, then as the point moves around the circle its and coordinates are the cosine and sine of .

(1,0)

θ

(1,0)

x

y

θ