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---
title: Math.cbrt()
slug: Web/JavaScript/Reference/Global_Objects/Math/cbrt
tags:
- JavaScript
- Math
- Method
- Reference
- 세제곱근
translation_of: Web/JavaScript/Reference/Global_Objects/Math/cbrt
---
<div>{{JSRef}}</div>
<p><span class="seoSummary"><strong><code>Math.cbrt()</code></strong> 함수는 주어진 수의 세제곱근을 반환합니다.</span> 즉,</p>
<p><math display="block"><semantics><mrow><mstyle mathvariant="monospace"><mrow><mi>M</mi><mi>a</mi><mi>t</mi><mi>h</mi><mo>.</mo><mi>c</mi><mi>b</mi><mi>r</mi><mi>t</mi><mo stretchy="false">(</mo><mi>x</mi><mo stretchy="false">)</mo></mrow></mstyle><mo>=</mo><mroot><mi>x</mi><mn>3</mn></mroot><mo>=</mo><mtext>the unique</mtext><mspace width="thickmathspace"></mspace><mi>y</mi><mspace width="thickmathspace"></mspace><mtext>such that</mtext><mspace width="thickmathspace"></mspace><msup><mi>y</mi><mn>3</mn></msup><mo>=</mo><mi>x</mi></mrow><annotation encoding="TeX">\mathtt{Math.cbrt(x)} = \sqrt[3]{x} = \text{the unique} \; y \; \text{such that} \; y^3 = x</annotation></semantics></math></p>
<h2 id="구문">구문</h2>
<pre class="syntaxbox"><code>Math.cbrt(<var>x</var>)</code></pre>
<h3 id="매개변수">매개변수</h3>
<dl>
<dt><code>x</code></dt>
<dd>숫자.</dd>
</dl>
<h3 id="반환_값">반환 값</h3>
<p>주어진 수의 세제곱근.</p>
<h2 id="설명">설명</h2>
<p><code>cbrt()</code>는 <code>Math</code>의 정적 메서드이므로, 사용자가 생성한 <code>Math</code> 객체의 메서드로 호출할 수 없고 항상 <code>Math.cbrt()</code>를 사용해야 합니다. (<code>Math</code>는 생성자가 아닙니다)</p>
<h2 id="예제">예제</h2>
<h3 id="Math.cbrt()_사용하기"><code>Math.cbrt()</code> 사용하기</h3>
<pre class="brush: js">Math.cbrt(NaN); // NaN
Math.cbrt(-1); // -1
Math.cbrt(-0); // -0
Math.cbrt(-Infinity); // -Infinity
Math.cbrt(0); // 0
Math.cbrt(1); // 1
Math.cbrt(Infinity); // Infinity
Math.cbrt(null); // 0
Math.cbrt(2); // 1.2599210498948734
</pre>
<h2 id="폴리필">폴리필</h2>
<p>모든 <math><semantics><mrow><mi>x</mi><mo>≥</mo><mn>0</mn></mrow><annotation encoding="TeX">x \geq 0</annotation></semantics></math>에서 <math><semantics><mrow><mroot><mi>x</mi><mn>3</mn></mroot><mo>=</mo><msup><mi>x</mi><mrow><mn>1</mn><mo>/</mo><mn>3</mn></mrow></msup></mrow><annotation encoding="TeX">\sqrt[3]{x} = x^{1/3}</annotation></semantics></math> 이므로, <code>Math.cbrt()</code>는 다음 함수로 폴리필할 수 있습니다.</p>
<pre class="brush: js">if (!Math.cbrt) {
Math.cbrt = (function(pow) {
return function cbrt(){
// ensure negative numbers remain negative:
return x < 0 ? -pow(-x, 1/3) : pow(x, 1/3);
};
})(Math.pow); // localize Math.pow to increase efficiency
}</pre>
<h2 id="명세">명세</h2>
<table class="standard-table">
<tbody>
<tr>
<th scope="col">Specification</th>
<th scope="col">Status</th>
<th scope="col">Comment</th>
</tr>
<tr>
<td>{{SpecName('ES6', '#sec-math.cbrt', 'Math.cbrt')}}</td>
<td>{{Spec2('ES6')}}</td>
<td>Initial definition.</td>
</tr>
<tr>
<td>{{SpecName('ESDraft', '#sec-math.cbrt', 'Math.cbrt')}}</td>
<td>{{Spec2('ESDraft')}}</td>
<td> </td>
</tr>
</tbody>
</table>
<h2 id="브라우저_호환성">브라우저 호환성</h2>
<p>{{Compat("javascript.builtins.Math.cbrt")}}</p>
<h2 id="같이_보기">같이 보기</h2>
<ul>
<li>{{jsxref("Math.pow()")}}</li>
<li>{{jsxref("Math.sqrt()")}}</li>
</ul>
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