Tangent function

Definition

The tangent function is defined by $\tan x = \frac{\sin x}{\cos x}$ for all real $x$ with $\cos x \ne 0$ , that is, for $x \ne \frac{\pi}{2} + k \pi$ with $k \in \mathbb{Z}$ .

Remarks

The function is odd and periodic with period $\pi$ . On $(-\pi/2, \pi/2)$ it is strictly increasing, and it maps this interval onto $\mathbb{R}$ . The related functions are $\cot x = \cos x / \sin x$ , $\sec x = 1 / \cos x$ and $\csc x = 1 / \sin x$ . Mathlib defines Real.tan with the value $0$ where $\cos x = 0$ .

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Sequence definition
Real sequence definition
Series definition
Power series definition
Sine and cosine definition
Tangent function definition

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8 pages build on this one.

Tag	`06T0HS14PP`
URI	`m2://06T0HS14PP`
Kind	definition
Writing	W0 stub
MSC	33B10
Defines	Tangent function
Uses	Sine and cosine

Tangent function

Definition

Remarks

Reading path

Where this leads

Further reading

What this page needs for W1

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