Trigonometric functions

The well known trigonometric functions can be visualized on the circle of radius 1. See http://en.wikipedia.org/wiki/Trigonometric_functions for the definitions.

• Tangent: [math]\displaystyle{ \tan x = \frac{\sin x}{\cos x} }[/math]
• Secant [math]\displaystyle{ \sec x = \frac{1}{\cos x} }[/math]