MathJax works on Github, too. Any math you write on Github (in a readme or issue for example) will render here in the same way.

I’ve only set up code blocks to render math for now, so no inline notation.

Invoke

```math
\left( \sum_{k=1}^n a_k b_k \right)^2 \leq \left( \sum_{k=1}^n a_k^2 \right) \left( \sum_{k=1}^n b_k^2 \right)
```