MathJax sandbox:

Here’s some maths to test the MathJax include:

\[\frac{1}{\displaystyle 1+ \frac{1}{\displaystyle 2+ \frac{1}{\displaystyle 3+x}}} + \frac{1}{1+\frac{1}{2+\frac{1}{3+x}}}\]

I’d also like to check symbols like these: $\hat{x}, \check{x}, \tilde{a}, \bar{\ell}, \dot{y}, \ddot{y}, \vec{z_1}, \vec{z}_1$

Also, the inline $a + b = c$ should work without affecting line spacing.

Let’s draw a pretty butterfly:

\begin{align} \dot{x} & = \sigma(y-x) \\ \dot{y} & = \rho x - y - xz \\ \dot{z} & = -\beta z + xy \end{align}

…and now, ‘Let there be light’:

\begin{align} \nabla \times \vec{\mathbf{B}} -\, \frac1c\, \frac{\partial\vec{\mathbf{E}}}{\partial t} & = \frac{4\pi}{c}\vec{\mathbf{j}} \\ \nabla \cdot \vec{\mathbf{E}} & = 4 \pi \rho \\ \nabla \times \vec{\mathbf{E}}\, +\, \frac1c\, \frac{\partial\vec{\mathbf{B}}}{\partial t} & = \vec{\mathbf{0}} \\ \nabla \cdot \vec{\mathbf{B}} & = 0 \end{align}