MathJax is now enabled for this site. For example, here are the Lorenz's equations:
\begin{aligned} \dot{x} & = \sigma(y-x) \\ \dot{y} & = \rho x - y - xz \\ \dot{z} & = -\beta z + xy \end{aligned}
which is created by
\begin{aligned}
\dot{x} & = \sigma(y-x)\\
\dot{y} & = \rho x - y - xz\\
\dot{z} & = -\beta z + xy
\end{aligned}
To setup MathJaX with Joomla! is easy. See this article.