# Math.pow()

`Math.pow()` 函式回傳 `base``exponent` 次方（幂）值，也就是 `baseexponent`

## 語法

``Math.pow(base, exponent)``

### 參數

`base`

`exponent`

### 回傳值

A number representing the given base taken to the power of the given exponent.

## 敘述

The `Math.pow()` function returns the `base` to the `exponent` power, that is, `baseexponent`, the base and the exponent are in decimal numeral system.

## 示例

### 使用 `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 （4 的平方根）
Math.pow(8, 1/3);  // 2 （8 的立方根）
Math.pow(2, 0.5);  // 1.4142135623730951 （2 的平方根）
Math.pow(2, 1/3);  // 1.2599210498948732 （2 的立方根）
// signed exponents
Math.pow(7, -2);   // 0.02040816326530612 (1/49)
Math.pow(8, -1/3); // 0.5
// signed bases
Math.pow(-7, 2);   // 49 (負負得正，2次方都是正數)
Math.pow(-7, 3);   // -343 (3次方有可能為負數)
Math.pow(-7, 0.5); // NaN (負數沒辦法得出一個實數平方根)
// 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
```

## 規範

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 (ECMA-262)
The definition of 'Math.pow' in that specification.
Living Standard

## 瀏覽器相容性

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