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+<head>
+  <link href="../favicon.ico" rel="shortcut icon" type="image/x-icon"/>
+  <link href="../style.css" rel="stylesheet"/>
+  <title>BQN: Superscript Equals Sign (`⁼`)</title>
+</head>
+<div class="nav">(<a href="https://github.com/mlochbaum/BQN">github</a>) / <a href="../index.html">BQN</a> / <a href="index.html">help</a></div>
+<h1 id="superscript-equals-sign-"><a class="header" href="#superscript-equals-sign-">Superscript Equals Sign (<code><span class='Modifier'>⁼</span></code>)</a></h1>
+<h2 id="-----undo"><a class="header" href="#-----undo"><code><span class='Function'>𝔽</span><span class='Modifier'>⁼</span> <span class='Value'>𝕩</span></code>, <code><span class='Value'>𝕨</span> <span class='Function'>𝔽</span><span class='Modifier'>⁼</span> <span class='Value'>𝕩</span></code>: Undo</a></h2>
+<p>Invert the function <code><span class='Function'>𝔽</span></code>, or use its defined inverse. Not all functions have inverses.</p>
+<a class="replLink" title="Open in the REPL" target="_blank" href="https://mlochbaum.github.io/BQN/try.html#code=ICAgMSAtIDIKCiAgIDEgLeKBvCAyCgogICDiiJogMTYKCiAgIOKImuKBvCA0CgogICDii4YgMQoKICAg4ouG4oG8IDIuNzE4MjgxODI4NDU5MDQ1">↗️</a><pre>       <span class='Number'>1</span> <span class='Function'>-</span> <span class='Number'>2</span>
+¯1
+
+       <span class='Number'>1</span> <span class='Function'>-</span><span class='Modifier'>⁼</span> <span class='Number'>2</span>
+¯1
+
+       <span class='Function'>√</span> <span class='Number'>16</span>
+4
+
+       <span class='Function'>√</span><span class='Modifier'>⁼</span> <span class='Number'>4</span>
+16
+
+       <span class='Function'>⋆</span> <span class='Number'>1</span>
+2.718281828459045
+
+       <span class='Function'>⋆</span><span class='Modifier'>⁼</span> <span class='Number'>2.718281828459045</span>
+1
+</pre>