\documentclass[11pt]{article}
\usepackage[francais]{babel}
\usepackage[T1]{fontenc}
\usepackage{amssymb}
\usepackage{fancyheadings}
\textheight25.5cm
%%\textwidth19cm
\voffset-3.5cm
%%\hoffset-3.3cm
\newcommand{\somm}[3]
{
\renewcommand{\arraystretch}{0.5}
\begin{array}{c}
{\scriptscriptstyle #1}\\
#2\\
{\scriptscriptstyle #3}
\end{array}
\renewcommand{\arraystretch}{1}
}
\renewcommand{\refname}{REFERENCES}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{document}
\thispagestyle{empty}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\noindent {\bf Universit\'e de Nice - Sophia Antipolis}
\hfill  {\bf Deug MIASSM \  TC (Gr 12)}\\
{\bf Ann\'ee 2001 - 2002}
%%\rule{19cm}{.1mm}
%%\rule{12.6cm}{.1mm}
\begin{center}
$\longrightarrow\longleftarrow$
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\fbox{
Interrogation \'ecrite de M\'ethodologie du 6 Novembre 2001 -  
Dur\'ee: 20mn
}
$\longrightarrow\longleftarrow$
\end{center}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%\rule{12.6cm}{.1mm}
%%\\
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\medskip
\noindent
{\bf Exercice 1} \ \ (4 points)
\\
\noindent
Evaluer, nier puis traduire informellement l'\'enonc\'e suivant:
$$
\forall x\in {\mathbb R}, \exists n\in {\mathbb N}, x\geq n \ \mbox{et} \
x<n+1
$$
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%\rule{12.6cm}{.1mm}
%%\\
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\medskip
\noindent
{\bf Exercice 2} \ \  (4 points)
\\
Evaluer, nier puis formuler la contrapos\'ee et la r\'eciproque de
l'\'enonc\'e suivant:
$$
\forall x,y\in {\mathbb N}, x\leq y \Longrightarrow cos(x)\leq cos(y)
$$
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%\rule{12.6cm}{.1mm}
%%\\
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\medskip
\noindent
{\bf Exercice 3} \ \  (2 points)
\\
Proposer une interpr\'etation formelle pour l'\'enonc\'e suivant:
\begin{center}
{\sl la multiplication des nombres complexes est commutative
}
\end{center}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\rule{12.6cm}{.1mm}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\end{document}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
