


\begin{exercice}
Associer chaque courbe à la bonne fonction dans chacun des cas.
  \begin{enumerate}
  \item $f(x)=-2(x+1)^2+4$ et $g(x)=3(x-2)^2+1$.
  \begin{center}
  \begin{tikzpicture}[general, xscale=0.8, yscale=0.42] 
   \draw[quadrillage, xstep=0.5] (-4,-3) grid (4,7);
   \axeX{-4}{4}{-2,2}
   \axeY{-3}{7}{-2,2, 4, 6} 
   \origine
   \draw[color=A1, smooth, samples=200, domain=-2.871:0.871, epais] plot (\x,-2*\x*\x-4*\x+2);
   \draw[color=C1, smooth, samples=200, domain=0.586:3.414, epais] plot (\x,3*\x*\x-12*\x+13);
  \end{tikzpicture}
  \end{center}
  \item $f(x)=2(x-1)^2+3$ et $g(x)=4(x-1)^2+3$.
  \begin{center} \begin{tikzpicture}[general, xscale=0.8, yscale=0.24]
   \draw[quadrillage, xstep=0.5, ystep=2] (-3,-2) grid (5,16);
   \axeX{-3}{5}{-2,-1,1,2,3,4}
   \axeY{-2}{16}{4,8,12} 
   \origine
   \draw[color=C1, smooth, samples=200, domain=-1.55:3.55, epais, line cap=butt] plot (\x,2*\x*\x-4*\x+5);
   \draw[color=A1, smooth, samples=200, domain=-0.803:2.803, epais, line cap=butt] plot (\x,4*\x*\x-8*\x+7);
  \end{tikzpicture}
  \end{center}
  \item $f(x)=2(x-2)^2-3$ et $g(x)=2(x-3)^2-2$.
  \begin{center} 
   \begin{tikzpicture}[general, xscale=0.8, yscale=0.42] \shorthandoff{:}
   \draw[quadrillage, xstep=0.5] (-2,-4) grid (6,6);
   \draw[axe] (-2,0)--(6,0);
   \draw[axe] (0,-4)--(0,6);
   \draw[color=A1, smooth, samples=200, domain=-0.121:4.121, epais] plot (\x,2*\x*\x-8*\x+5);
   \draw[color=C1, smooth, samples=200, domain=1:5, epais] plot (\x,2*\x*\x-12*\x+16);
   \foreach \x in {-1,1,2,3, 4, 5} {\draw (\x,0) node {\footnotesize $+$};\draw (\x,0) node[below] {\footnotesize $\x$};}
   \foreach \y in {-3,-2,-1,1,2,3, 4, 5} {\draw (0,\y) node {\footnotesize $+$};\draw (0,\y) node[left] {\footnotesize $\y$};}
  \end{tikzpicture}
  \end{center}
 \end{enumerate}
\end{exercice}
