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\noindent {\bf Universit\'e de Nice - Sophia Antipolis}
\hfill  {\bf Deug MIASSM \  TC (Gr 12)}\\
{\bf Ann\'ee 2001 - 2002}
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$\longrightarrow\longleftarrow$
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\fbox{
Interrogation \'ecrite de M\'ethodologie du 6 Novembre 2001 -  
Dur\'ee: 20mn
}
$\longrightarrow\longleftarrow$
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\medskip
\noindent
{\bf Exercice 1} \ \ (4 points)
\\
\noindent
Evaluer, nier puis traduire informellement l'\'enonc\'e suivant:
$$
\forall x\in {\mathbb R}, \exists n\in {\mathbb N}, x\geq n \ \mbox{et} \
x<n+1
$$
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\medskip
\noindent
{\bf Exercice 2} \ \  (4 points)
\\
Evaluer, nier puis formuler la contrapos\'ee et la r\'eciproque de
l'\'enonc\'e suivant:
$$
\forall x,y\in {\mathbb N}, x\leq y \Longrightarrow cos(x)\leq cos(y)
$$
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\medskip
\noindent
{\bf Exercice 3} \ \  (2 points)
\\
Proposer une interpr\'etation formelle pour l'\'enonc\'e suivant:
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{\sl la multiplication des nombres complexes est commutative
}
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