Trigonometric functions

Definition

Trigonometric functions relate angles in a right triangle to ratios of side lengths. The six main trigonometric functions are sine (sin), cosine (cos), tangent (tan), cosecant (csc), secant (sec), and cotangent (cot).

Related terms

Unit circle: A circle with radius 1 centered at the origin used to define trigonometric values for any angle.

Periodicity: The property of trigonometric functions that repeats their values after certain intervals.

Inverse trigonometric functions: Functions that "undo" the effects of trigonometric functions by finding angles given specific ratios.