Add the following code to the top of your Markdown files to get MathJax rendering support
<style TYPE="text/css">
code.has-jax {font: inherit; font-size: 100%; background: inherit; border: inherit;}
</style>
<script type="text/x-mathjax-config">
MathJax.Hub.Config({
tex2jax: {
inlineMath: [['$','$'], ['\\(','\\)']],
skipTags: ['script', 'noscript', 'style', 'textarea', 'pre'] // removed 'code' entry
}
});
MathJax.Hub.Queue(function() {
var all = MathJax.Hub.getAllJax(), i;
for(i = 0; i < all.length; i += 1) {
all[i].SourceElement().parentNode.className += ' has-jax';
}
});
</script>
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.4/MathJax.js?config=TeX-AMS_HTML-full"></script>
and then `$x^2$` or `$$x^2$$` will render as expected :-)
You can always install a local version of MathJax if you don't want to use the online distribution, but you might need to host it through a local webserver.
UPDATE: these days I just use pandoc instead of canonical markdown, but the above is still useful.