\documentclass[a4paper,12pt]{book}
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\newtheorem{thm}{\grasoul{\red{THÉORÈME }}}
\newtheorem{rmq}{\grasoul{\green{Remarque }}}
\newtheorem{ex}{\grasoul{\blue{Exemple}}}
%Tapuscrit : leonidasse DIMANCHE
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\def\Ouv{$\left(\text{O}~;~\vect{u},~\vect{v}\right)$}

\usepackage{hyperref}

\usepackage[np]{numprint}

\title{\textbf{Cours de quatrième}}
\author{L DIMANCHE}

\begin{document}

\maketitle
\tableofcontents

%Chapitre 1
\chapter{}
\section*{I)}


\end{document}