\documentclass[12pt]{ctexart}

\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{geometry}
\usepackage{hyperref}
\usepackage{graphicx}
\usepackage{dsfont}

% --- 页面设置 ---
\geometry{a4paper, left=2.5cm, right=2.5cm, top=2.5cm, bottom=2.5cm}

% --- 标题信息 ---
\title{\textbf{习题课讲义}}
\author{TA: 于洪飞}
\date{\today}

% --- 命令定义 ---
\renewcommand{\vec}[1]{\boldsymbol{#1}}
\newcommand{\mat}[1]{\mathbf{#1}}
\newcommand{\uvect}[1]{\hat{\mathbf{e}}_{#1}}

\begin{document}

\maketitle
\thispagestyle{empty}

\input{contents/1.tex}


\end{document}