JavaScript: The Definitive Guide, Fourth Edition

Name

Math.sqrt( ) — compute a square root

Availability

JavaScript 1.0; JScript 1.0; ECMAScript v1

Synopsis

Math.sqrt(x)

Arguments

x

A numeric value greater than or equal to zero.

Returns

The square root of x. Returns NaN if x is less than zero.

Description

Math.sqrt( ) computes the square root of a number. Note, however, that you can compute arbitrary roots of a number with Math.pow( ). For example:

Math.cuberoot = function(x){ return Math.pow(x,1/3); }
Math.cuberoot(8);  // Returns 2