\begin{exercice} Pour chacune des suites représentées graphiquement ci-dessous, conjecturer un majorant, un minorant ou un encadrement.

\begin{enumerate}
  \vspace{-0.5\baselineskip}\item ~~

  \vspace{-1.75\baselineskip}
  \begin{center}
  \begin{tikzpicture}[general,xscale=.5,yscale=0.5]
  \draw[quadrillageNIV2, xstep=1, ystep=1](0,0) grid(10,7);

\axeX{0}{10}{0,1,2,3,4,5,6,7,8,9,10};
\axeY{0}{7}{0,1,2,3,4,5,6,7};

%u_n=4+2(-1)^n/(n+1)

\draw [color=C1]  (0,6) node {$\bullet$};
\draw [color=C1]  (1,3) node {$\bullet$};
\draw [color=C1]  (2,4.667) node {$\bullet$};
\draw [color=C1] (3,3.5) node {$\bullet$};
\draw [color=C1] (4,4.4) node {$\bullet$};
\draw [color=C1] (5,3.667) node {$\bullet$};
\draw [color=C1] (6,4.286) node {$\bullet$};
\draw [color=C1] (7,3.75) node {$\bullet$};
\draw [color=C1] (8,4.222) node {$\bullet$};
\draw [color=C1] (9,3.8) node {$\bullet$};
\draw [color=C1] (10,4.182) node {$\bullet$};
    \end{tikzpicture}
  \end{center}
    \vspace{-0.5\baselineskip}\item ~~

  \vspace{-1.5\baselineskip}
  \begin{center}
  \begin{tikzpicture}[general,xscale=.5,yscale=0.5]
  \draw[quadrillageNIV2, xstep=1, ystep=1](0,0) grid(10,7);

\axeX{0}{10}{0,1,2,3,4,5,6,7,8,9,10};
\axeY{0}{7}{0,1,2,3,4,5,6,7};

%u_n=6-3/(n+1)

\draw [color=C1]  (0,3) node {$\bullet$};
\draw [color=C1]  (1,4.5) node {$\bullet$};
\draw [color=C1]  (2,5) node {$\bullet$};
\draw [color=C1] (3,5.25) node {$\bullet$};
\draw [color=C1] (4,5.4) node {$\bullet$};
\draw [color=C1] (5,5.5) node {$\bullet$};
\draw [color=C1] (6,5.571) node {$\bullet$};
\draw [color=C1] (7,5.625) node {$\bullet$};
\draw [color=C1] (8,5.667) node {$\bullet$};
\draw [color=C1] (9,5.7) node {$\bullet$};
\draw [color=C1] (10,5.727) node {$\bullet$};
    \end{tikzpicture}
  \end{center}

  \vspace{-0.5\baselineskip}\item ~~

  \vspace{-1.75\baselineskip}
  \begin{center}
  \begin{tikzpicture}[general,xscale=.5,yscale=.04]
  \draw[quadrillageNIV2, xstep=1, ystep=10](0,-100) grid(10,20);

\axeX{0}{10}{1,2,3,4,5,6,7,8,9,10};
\axeY{-100}{20}{-100,-90,-80,-70,-60,-50,-40,-30,-20,-10,0,10,20};

%u_n=-n^2+10
\draw [color=C1]  (0,10) node {$\bullet$};
\draw [color=C1]  (1,9) node {$\bullet$};
\draw [color=C1]  (2,6) node {$\bullet$};
\draw [color=C1]  (3,1) node {$\bullet$};
\draw [color=C1] (4,-6) node {$\bullet$};
\draw [color=C1] (5,-15) node {$\bullet$};
\draw [color=C1] (6,-26) node {$\bullet$};
\draw [color=C1] (7,-39) node {$\bullet$};
\draw [color=C1] (8,-54) node {$\bullet$};
\draw [color=C1] (9,-71) node {$\bullet$};
\draw [color=C1] (10,-90) node {$\bullet$};
    \end{tikzpicture}
  \vspace{-0.5\baselineskip}\end{center}
  \item ~~

  \vspace{-1.75\baselineskip}
  \begin{center}
  \begin{tikzpicture}[general,x=1.0cm,y=1.0cm]
\draw[quadrillageNIV2, xstep=0.5, ystep=0.5] (0,0) grid (3.6,3.6);

\axeX{0}{3.6}{0,1};
\axeY{0}{3.6}{0,1};

%\clip(-0.75,-0.6) rectangle (3.6,3.6);
\draw[smooth,samples=100,domain=0:3.6,color=J1] plot(\x,{3-0.5*(\x)});
\draw [domain=0:3.6,color=BleuOuv] plot(\x,{(-0--1*\x)/1});
\draw [Noir,dashed,thin] (0.5,0)-- (0.5,2.75);
\draw [Noir,dashed,thin](0.5,2.75)-- (2.75,2.75);
\draw [Noir,dashed,thin](2.75,2.75)-- (2.75,0);
\draw [Noir,dashed,thin](2.75,1.63)-- (1.63,1.63);
\draw [Noir,dashed,thin](1.63,1.63)-- (1.63,0);
\draw [Noir,dashed,thin](1.63,1.63)-- (1.63,2.19);
\draw [Noir,dashed,thin](1.63,2.19)-- (2.19,2.19);
\draw [Noir,dashed,thin](2.19,2.19)-- (2.19,0);
\draw (0.5,0) node[below,color=F1] {$u_0$};
\draw (2.75,0) node[below,color=F1] {$u_1$};
\draw (1.63,0) node[below,color=F1] {$u_2$};
\end{tikzpicture}
  \end{center}
\end{enumerate}
\end{exercice}

