Writing maths works as in LaTeX. Use dollar signs to enclose inline math, e.g. \(x^2\) \(x^2\) \(x^2\) $$x^2$$
\(
\begin{align}
E &= mc^2 \\
m &= \frac{m_0}{\sqrt{1-\frac{v^2}{c^2}}}
\end{align}
\)
\(\int_{-\infty}^\infty e^{-\pi x^2}\,\mathrm{d}x=1\label{a}\tag{1}\)
| \ref{a} |