main.tex

\documentclass[12pt]{article}
\usepackage{amsmath}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{geometry}
\usepackage{xcolor}

\title{Sample LaTeX Document}
\author{Your Name}
\date{\today}

\begin{document}

\maketitle

\section{Introduction}
This is a sample LaTeX document with the given preamble.

\section{Mathematics}
Here are some mathematical symbols and equations using the packages you've included:

\begin{enumerate}
    \item Set of natural numbers: $\mathbb{N}$
    \item Set of integers: $\mathbb{Z}$
    \item A quadratic equation: $ax^2 + bx + c = 0$
    \item A matrix:
    \[
    \begin{bmatrix}
    a & b \\
    c & d \\
    \end{bmatrix}
    \]
\end{enumerate}

\section{Colored Text}
Here's some text in \textcolor{red}{red}, \textcolor{blue}{blue}, and \textcolor{green}{green}.

\section{Conclusion}
This document demonstrates some basic features provided by the packages in the preamble.

\end{document}