HaTeX-3.10.0.0: parsertest/example3.tex

\documentclass{article}
\begin{document}

\section{Math formulae}

$\lambda (2+2) = 4$

\[\lambda (2+2) = 4\]

\(\lambda (2+2) = 4\)

\begin{displaymath}
\lambda (2+2) = 4
\end{displaymath}
\end{document}