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The Math.pow()
function returns the base
to the exponent
power, that is, baseexponent
.
Syntax
Math.pow(base, exponent)
Parameters
base
- The base number.
exponent
- The exponent used to raise the
base
.
Return value
A number representing the given base taken to the power of the given exponent.
Description
Because pow()
is a static method of Math
, you always use it as Math.pow()
, rather than as a method of a Math
object you created (Math
has no constructor).
Examples
Using Math.pow()
// simple Math.pow(7, 2); // 49 Math.pow(7, 3); // 343 Math.pow(2, 10); // 1024 // fractional exponents Math.pow(4, 0.5); // 2 (square root of 4) Math.pow(8, 1/3); // 2 (cube root of 8) Math.pow(2, 0.5); // 1.4142135623730951 (square root of 2) Math.pow(2, 1/3); // 1.2599210498948732 (cube root of 2) // signed exponents Math.pow(7, -2); // 0.02040816326530612 (1/49) Math.pow(8, -1/3); // 0.5 // signed bases Math.pow(-7, 2); // 49 (squares are positive) Math.pow(-7, 3); // -343 (cubes can be negative) Math.pow(-7, 0.5); // NaN (negative numbers don't have a real square root) // due to "even" and "odd" roots laying close to each other, // and limits in the floating number precision, // negative bases with fractional exponents always return NaN Math.pow(-7, 1/3); // NaN
Specifications
Specification | Status | Comment |
---|---|---|
ECMAScript 1st Edition (ECMA-262) | Standard | Initial definition. Implemented in JavaScript 1.0. |
ECMAScript 5.1 (ECMA-262) The definition of 'Math.pow' in that specification. |
Standard | |
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'Math.pow' in that specification. |
Standard | |
ECMAScript 2017 Draft (ECMA-262) The definition of 'Math.pow' in that specification. |
Draft |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |
Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |
See also
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