Below is an example of maths using mathjax.
Any page needing maths should start with the frontmatter:
usemathjax: true
\[\begin{align*} y = y(x,t) &= A e^{i\theta} \\ &= A (\cos \theta + i \sin \theta) \\ &= A (\cos(kx - \omega t) + i \sin(kx - \omega t)) \\ &= A\cos(kx - \omega t) + i A\sin(kx - \omega t) \\ &= A\cos \Big(\frac{2\pi}{\lambda}x - \frac{2\pi v}{\lambda} t \Big) + i A\sin \Big(\frac{2\pi}{\lambda}x - \frac{2\pi v}{\lambda} t \Big) \\ &= A\cos \frac{2\pi}{\lambda} (x - v t) + i A\sin \frac{2\pi}{\lambda} (x - v t) \end{align*}\]
Inline maths can be written with the \\( and \\) characters, producing inline maths such as \(\delta(t) \xrightarrow{\mathscr{F}} 1\).
The above is accomplished with thanks to Alan Duan and Zichen Vincent Zhang.