Unit Circle and Trigonometric Functions

Sine and cosine have a simple geometric interpretation, as x and y values of a point on the unit circle.
Try it by yourself.

30°
360°
Comments

While the \( \sin \) and \( \cos \) functions take an angle as input, they can be used to describe sinusoidal signals like \( \sin(\omega t) \), with \( \omega = 2\pi f \), where \( f \) is the frequency of the signal. The period of such a signal corresponds to \( \omega T = 2\pi \), i.e., \( T = \frac{1}{f} \).