math-elements
This library implements a couple custom elements to easily work with formatted math expressions in html.
<math-inline>allows you to display an expression within paragraph text<math-display>centers an expression on a new line
Here's a screenshot:
You'll need to use a polyfill for custom elements to display these elements. Either the Polymer or X-Tag frameworks supply a polyfill, or you can install the standalone CustomElements one:
<script src="https://cdnjs.cloudflare.com/ajax/libs/custom-elements/1.0.4/custom-elements.min.js"></script>