HTML

How to write the latex in html

This helps you to write math eq'n inline:
<script type="text/x-mathjax-config">
	MathJax.Hub.Config({tex2jax: {inlineMath: [['$','$'], ['(',')']]}});
</script>
<script type="text/javascript"
	src="http://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.1/MathJax.js?config=TeX-AMS-MML_HTMLorMML">
</script> 

latex in html

<script src="https://polyfill.io/v3/polyfill.min.js?features=es6"></script>
<script>
  MathJax = {
    tex: {inlineMath: [['$', '$'], ['(', ')']]}
  };
</script>
<script id="MathJax-script" async src="https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-chtml.js"></script>