\documentclass{article}
\title{Question 4}
\author{Rakshit Rabugotra}
\date{}

\begin{document}

\section{List of Mathematical functions}
\begin{itemize}
\item Trigonometric functions
\begin{itemize}
\item[-]sine
\item[-]cosine
\item[-]tangent
\end{itemize}
\item Special functions
\begin{itemize}
\item[-]Beta function
\item[-]Gamma function
\item[-]Riemann zeta function
\end{itemize}
\end{itemize}

\end{document}