Unit Circle and Cosine/Sine Functions
(By Thomas Scofield)
\textrm{The angle } \theta \textrm{ determines the direction of the (red)
ray. The values of } \cos(\theta), \sin(\theta) \textrm{ are the } x, y
\textrm{ coordinates} \\
\textrm{(respectively) of the (black) point of intersection
between the ray and the (black) unit circle. }
Last modified on July 24, 2017.