title: Jupyter markdown: Curly brace symbole doesn't show correctly
body: <p>I am trying to write a mathematical equation in jupyter notebook markdown, this equation have a Curly brace '{' symbole.
  I wrote this code : <br></p>
  
  <pre><code>$$M=\begin{equation}
  \left\{ 
    \begin{aligned}
      2\,x&amp;+3\,y&amp;-4\,z&amp;=&amp;7\\
      -x&amp;+8\,y&amp;   &amp;=&amp;3\\
      \frac{2}{3}\,x&amp;+\frac{13}{2}\,y&amp;-5\,z&amp;=&amp;\frac{14}{5}\\
    \end{aligned}
    \right.
  \end{equation}
  $$
  </code></pre>
  
  <p><br>
  when running the cell I get this:<br></p>
  
  <p><a href="https://i.stack.imgur.com/92PSc.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/92PSc.png" alt="enter image description here"></a></p>
  
  <p>instead of the correct one: <br>
  <a href="https://i.stack.imgur.com/hFFAp.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/hFFAp.png" alt="enter image description here"></a></p>
  
  <p>So I don't know what the problem is, any idea?
  PS: I have python3</p>