GitHub PagesでMathJaxを使用するためのコード例。

mathjax.html

{% if page.mathjax %}
<script type="text/x-mathjax-config">
MathJax.Hub.Config({
  displayAlign: "left",
  displayIndent: "2em",
  TeX: {
    equationNumbers: { autoNumber: "AMS" },
  },
  tex2jax: {
    inlineMath: [['$','$'], ['\\(','\\)']],
    processEscapes: true
  }
});
</script>
<script
  type="text/javascript"
  charset="utf-8"
  src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.1/MathJax.js?config=TeX-AMS-MML_HTMLorMML">
</script>
{% endif %}