Math.tanh()

A função Math.tanh()  retorna a tangente hiperbólica de um número, que é:

$tanhx=sinhxcoshx=ex-e-xex+e-x=e2x-1e2x+1\tanh x = \frac{\sinh x}{\cosh x} = \frac {e^x - e^{-x}} {e^x + e^{-x}} = \frac{e^{2x} - 1}{e^{2x}+1}$

Syntax

Math.tanh(x)

Parameters

x
Um número.

Return value

Uma tangente hiperbólica de um número dado.

Description

Because tanh() is a static method of Math, you always use it as Math.tanh(), rather than as a method of a Math object you created (Math is not a constructor).

Examples

Using Math.tanh()

Math.tanh(0);        // 0
Math.tanh(Infinity); // 1
Math.tanh(1);        // 0.7615941559557649


Polyfill

This can be emulated with the help of the Math.exp() function:

Math.tanh = Math.tanh || function(x){
var a = Math.exp(+x), b = Math.exp(-x);
return a == Infinity ? 1 : b == Infinity ? -1 : (a - b) / (a + b);
}


Specifications

Specification Status Comment
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'Math.tanh' in that specification.
ECMAScript (ECMA-262)
The definition of 'Math.tanh' in that specification.

Browser compatibility

Update compatibility data on GitHub
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