JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script>
\[
    \sum_{n = 1}^k b_n
\]

CSS

body {
      font-size: 2em;
    }