\begin{itemize}
  \item First item
  \item Second item with \textit{emphasis}
  \item Third item with an optional argument command \cmd[key=value]{body}
\end{itemize}

\begin{equation}
  \nabla \cdot \mathbf{E} = \frac{\rho}{\varepsilon_0}
\end{equation}

\begin{align}
  f(x) &= a x^2 + b x + c \\
  f'(x) &= 2 a x + b
\end{align}

\[
  \begin{pmatrix}
    1 & 22 \\
    333 & 4
  \end{pmatrix}
\]
