Math.tanh()

The Math.tanh() function returns the hyperbolic tangent of a number, that is

tanh x = sinh x cosh x = e x - e - x e x + e - x = e 2 x - 1 e 2 x + 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

A number.

Return value

The hyperbolic tangent of the given number.

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).

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);
}

Examples

Using Math.tanh()

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

Specifications

Specification
ECMAScript Language Specification
# sec-math.tanh

Browser compatibility

Report problems with this compatibility data on GitHub
desktopmobileserver
ChromeEdgeFirefoxInternet ExplorerOperaSafariWebView AndroidChrome AndroidFirefox for AndroidOpera AndroidSafari on iOSSamsung InternetDenoNode.js
tanh

Legend

Full support
Full support
No support
No support

See also