MathJax
mathjax/MathJax: Beautiful math in all browsers
Inline Example
Input
Inline $E = mc^2$
Output
Inline $E = mc^2$
Basic Example
Input
$$
\sum_{i=0}^n i^2 = \frac{(n^2+n)(2n+1)}{6}
$$
Output
$$ \sum_{i=0}^n i^2 = \frac{(n^2+n)(2n+1)}{6} $$Math Shortcode
See also this thread.
Input
{{< math >}}
\begin{vmatrix}a & b\\
c & d
\end{vmatrix}
{{< /math >}}