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---
title: Math.tanh()
slug: Web/JavaScript/Reference/Global_Objects/Math/tanh
tags:
- ECMAScript 2015
- JavaScript
- Math
- Method
- Reference
translation_of: Web/JavaScript/Reference/Global_Objects/Math/tanh
---
<div>{{JSRef}}</div>
<p>Die <strong><code>Math.tanh()</code></strong> Funktion gibt den Tangens Hyperbolicus einer Zahl zurück. Dieser kann folgendermaßen errechnet werden:</p>
<p><math display="block"><semantics><mrow><mo lspace="0em" rspace="0em">tanh</mo><mi>x</mi><mo>=</mo><mfrac><mrow><mo lspace="0em" rspace="0em">sinh</mo><mi>x</mi></mrow><mrow><mo lspace="0em" rspace="0em">cosh</mo><mi>x</mi></mrow></mfrac><mo>=</mo><mfrac><mrow><msup><mi>e</mi><mi>x</mi></msup><mo>-</mo><msup><mi>e</mi><mrow><mo>-</mo><mi>x</mi></mrow></msup></mrow><mrow><msup><mi>e</mi><mi>x</mi></msup><mo>+</mo><msup><mi>e</mi><mrow><mo>-</mo><mi>x</mi></mrow></msup></mrow></mfrac><mo>=</mo><mfrac><mrow><msup><mi>e</mi><mrow><mn>2</mn><mi>x</mi></mrow></msup><mo>-</mo><mn>1</mn></mrow><mrow><msup><mi>e</mi><mrow><mn>2</mn><mi>x</mi></mrow></msup><mo>+</mo><mn>1</mn></mrow></mfrac></mrow><annotation encoding="TeX">\tanh x = \frac{\sinh x}{\cosh x} = \frac {e^x - e^{-x}} {e^x + e^{-x}} = \frac{e^{2x} - 1}{e^{2x}+1}</annotation></semantics></math></p>
<div>{{EmbedInteractiveExample("pages/js/math-tanh.html")}}</div>
<h2 id="Syntax">Syntax</h2>
<pre class="syntaxbox"><code>Math.tanh(<var>x</var>)</code></pre>
<h3 id="Parameter">Parameter</h3>
<dl>
<dt><code>x</code></dt>
<dd>Eine Zahl.</dd>
</dl>
<h3 id="Rückgabewert">Rückgabewert</h3>
<p>Den Tangens Hyperbolicus der übergebenen Zahl.</p>
<h2 id="Beschreibung">Beschreibung</h2>
<p>Weil <code>tanh()</code> eine statische Funktion von <code>Math</code> ist, wird es immer als <code>Math.tanh()</code> eingesetzt<code>,</code> jedoch nicht als Methode eines erzeugten <code>Math</code> Objektes (<code>Math</code> ist kein Konstruktor).</p>
<h2 id="Beispiele">Beispiele</h2>
<h3 id="Einsatz_von_Math.tanh()">Einsatz von <code>Math.tanh()</code></h3>
<pre class="brush: js">Math.tanh(0); // 0
Math.tanh(Infinity); // 1
Math.tanh(1); // 0.7615941559557649
</pre>
<h2 id="Polyfill">Polyfill</h2>
<p>Diese Funktion kann mit Hilfe der Funktion {{jsxref("Math.exp()")}} emuliert werden:</p>
<pre class="brush: js line-numbers language-js"><code class="language-js">Math<span class="punctuation token">.</span>tanh <span class="operator token">=</span> Math<span class="punctuation token">.</span>tanh <span class="operator token">||</span> <span class="keyword token">function</span><span class="punctuation token">(</span>x<span class="punctuation token">)</span><span class="punctuation token">{</span>
<span class="keyword token">var</span> a <span class="operator token">=</span> Math<span class="punctuation token">.</span><span class="function token">exp</span><span class="punctuation token">(</span><span class="operator token">+</span>x<span class="punctuation token">)</span><span class="punctuation token">,</span> b <span class="operator token">=</span> Math<span class="punctuation token">.</span><span class="function token">exp</span><span class="punctuation token">(</span><span class="operator token">-</span>x<span class="punctuation token">)</span><span class="punctuation token">;</span>
<span class="keyword token">return</span> a <span class="operator token">==</span> <span class="number token">Infinity</span> <span class="operator token">?</span> <span class="number token">1</span> <span class="punctuation token">:</span> b <span class="operator token">==</span> <span class="number token">Infinity</span> <span class="operator token">?</span> <span class="operator token">-</span><span class="number token">1</span> <span class="punctuation token">:</span> <span class="punctuation token">(</span>a <span class="operator token">-</span> b<span class="punctuation token">)</span> <span class="operator token">/</span> <span class="punctuation token">(</span>a <span class="operator token">+</span> b<span class="punctuation token">)</span><span class="punctuation token">;</span>
<span class="punctuation token">}</span></code></pre>
<h2 id="Spezifikationen">Spezifikationen</h2>
<table class="standard-table">
<tbody>
<tr>
<th scope="col">Spezifikation</th>
<th scope="col">Status</th>
<th scope="col">Kommentar</th>
</tr>
<tr>
<td>{{SpecName('ES2015', '#sec-math.tanh', 'Math.tanh')}}</td>
<td>{{Spec2('ES2015')}}</td>
<td>Initiale Definition.</td>
</tr>
<tr>
<td>{{SpecName('ESDraft', '#sec-math.tanh', 'Math.tanh')}}</td>
<td>{{Spec2('ESDraft')}}</td>
<td> </td>
</tr>
</tbody>
</table>
<h2 id="Browserkompatibilität">Browserkompatibilität</h2>
<p>{{Compat("javascript.builtins.Math.tanh")}}</p>
<h2 id="Siehe_auch">Siehe auch</h2>
<ul>
<li>{{jsxref("Math.acosh()")}}</li>
<li>{{jsxref("Math.asinh()")}}</li>
<li>{{jsxref("Math.atanh()")}}</li>
<li>{{jsxref("Math.cosh()")}}</li>
<li>{{jsxref("Math.sinh()")}}</li>
</ul>
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