\documentclass{mathweb}
\graphicspath{{img/}}
\usepackage{tkz-graph}
\usetikzlibrary{matrix,arrows,decorations.pathmorphing}
\let\oldRe\Re
\let\oldIm\Im
\let\Re\relax
\let\Im\relax
\DeclareMathOperator{\Re}{\bgroup\rm\oldRe e\egroup}
\DeclareMathOperator{\Im}{\bgroup\rm\oldIm m\egroup}
\DeclareMathOperator{\rg}{\bgroup\rm rg\egroup}

\begin{document}
\frontmatter
\dominitoc
\couverture
\tableofcontents
\input{src/0-Preface}

\mainmatter

%\addtocontents{toc}{\protect\vspace*{-15mm}}


\input{src/01-Nombres complexes}
\input{src/02-Arithmetique}
\input{src/03-Matrices}
\input{src/04-Graphes}
\end{document}