# What is the trig unit circle? How does the trig circle define the trig functions?

##### 1 Answer

Jul 19, 2015

What is the trig unit circle?

#### Explanation:

It is a circle with radius R = 1. The variable arc AM = x rotates counterclockwise on the trig circle.

When M varies on the trig circle:

The horizontal axis OAx defines the function f(x) = cos x

The vertical axis OBy defines the function f(x) = sin x.

The vertical axis AT defines the function f(x) = tan x

The horizontal axis BU defines the function f(x) = cot x