The function <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle f:\mathbb {R} \to \mathbb {R} :x\mapsto {\begin{cases}x\cdot \sin \left({\tfrac {1}{x}}\right)&amp;x\neq 0\\0&amp;x=0\end{cases}}}"><semantics><mrow class="MJX-TeXAtom-ORD"><mstyle displaystyle="true" scriptlevel="0"><mi>f</mi><mo>:</mo><mrow class="MJX-TeXAtom-ORD"><mi mathvariant="double-struck">R</mi></mrow><mo stretchy="false">→<!-- → --></mo><mrow class="MJX-TeXAtom-ORD"><mi mathvariant="double-struck">R</mi></mrow><mo>:</mo><mi>x</mi><mo stretchy="false">↦<!-- ↦ --></mo><mrow class="MJX-TeXAtom-ORD"><mrow><mo>{</mo><mtable columnalign="left left" rowspacing=".2em" columnspacing="1em" displaystyle="false"><mtr><mtd><mi>x</mi><mo>⋅<!-- ⋅ --></mo><mi>sin</mi><mo>⁡<!-- ⁡ --></mo><mrow><mo>(</mo><mrow class="MJX-TeXAtom-ORD"><mstyle displaystyle="false" scriptlevel="0"><mfrac><mn>1</mn><mi>x</mi></mfrac></mstyle></mrow><mo>)</mo></mrow></mtd><mtd><mi>x</mi><mo>≠<!-- ≠ --></mo><mn>0</mn></mtd></mtr><mtr><mtd><mn>0</mn></mtd><mtd><mi>x</mi><mo>=</mo><mn>0</mn></mtd></mtr></mtable><mo fence="true" stretchy="true" symmetric="true"></mo></mrow></mrow></mstyle></mrow><annotation encoding="application/x-tex">{\displaystyle f:\mathbb {R} \to \mathbb {R} :x\mapsto {\begin{cases}x\cdot \sin \left({\tfrac {1}{x}}\right)&amp;x\neq 0\\0&amp;x=0\end{cases}}}</annotation></semantics></math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/fdb3a3917b2124622b0bf9bd44cfb813ce9e3aa6" class="mwe-math-fallback-image-inline" aria-hidden="true" style="vertical-align: -2.505ex; width:37.245ex; height:6.176ex;" alt="{\displaystyle f:\mathbb {R} \to \mathbb {R} :x\mapsto {\begin{cases}x\cdot \sin \left({\tfrac {1}{x}}\right)&amp;x\neq 0\\0&amp;x=0\end{cases}}}"></span>.
<a rel="nofollow" class="external text" href="http://kulla.me">Stephan Kulla</a> (<a href="//commons.wikimedia.org/wiki/User:Stephan_Kulla" title="User:Stephan Kulla">User:Stephan Kulla</a>)
2016-04-23
<span class="int-own-work" lang="en">Own work</span>