\begin{exercice*}\label{2G6_mental}On considère le cercle trigonométrique ci-dessous. 
Associer chacun des nombres à un point du cercle. 

\textit{Les segments rouges partagent le cercle en huit angles de 45\degre et les bleus partagent le cercle en douze angles de 30\degre.}
\begin{colenumerate}{4}
 \item $\dfrac{\TopStrut \pi}{\BotStrut 2}$
 \item $\dfrac{\TopStrut \pi}{\BotStrut 3}$
 \item $\dfrac{\TopStrut \pi}{\BotStrut  4}$
 \item $\dfrac{\TopStrut \pi}{\BotStrut 6}$
 \item $-\dfrac{\TopStrut \pi}{\BotStrut 2}$
 \item $-\dfrac{\TopStrut \pi}{\BotStrut 3}$
 \item $-\dfrac{\TopStrut \pi}{\BotStrut 4 }$
 \item $-\dfrac{\TopStrut \pi}{\BotStrut 6}$
%  \item $-\dfrac{\TopStrut 7\pi}{\BotStrut 6}$
%  \item $\dfrac{\TopStrut 4\pi}{\BotStrut 3}$
\end{colenumerate}


\begin{center}
\begin{tikzpicture}[general, scale=1.7]
 \draw (0,0) circle (1);
 \draw[color=A1] (1,0)--(-1,0);
 \draw[color=A1] (0,1)--(0,-1);
 \draw[color=C1, dashed] (1,0)--(-1,0);
 \draw[color=C1, dashed] (0,1)--(0,-1);
 \draw[color=A1] (0.87,0.5)--(-0.87,-0.5);
 \draw[color=A1] (0.5,0.87)--(-0.5,-0.87);
 \draw[color=A1] (-0.5,0.87)--(0.5,-0.87);
 \draw[color=A1] (-0.87,0.5)--(0.87,-0.5);
 \draw[color=C1] (0.71,0.71)--(-0.71,-0.71); 
 \draw[color=C1] (-0.71,0.71)--(0.71,-0.71); 
% \draw[color=A1] (0,0) circle (0.2);
% \draw[color=C1] (0,0) circle (0.4);
 \foreach \x/\y/\N/\pos in {1/0/I/right, 0.87/0.5/A/above right, 0.71/0.71/B/above right,0.5/0.87/C/above right, 0/1/J/above, -0.87/0.5/G/above left, -0.71/0.71/F/above left,-0.5/0.87/E/above left, -1/0/H/left, -0.87/-0.5/K/below left, -0.71/-0.71/L/below left,-0.5/-0.87/M/below left, 0/-1/N/below, 0.87/-0.5/T/below right, 0.71/-0.71/S/below right,0.5/-0.87/R/below right}{\draw (\x,\y) node[\pos]{$\N$};}
% \foreach \x/\y in {0.19/0.05, -0.19/-0.05, 0.19/-0.05, -0.19/0.05, 0.14/0.14, -0.14/0.14,-0.14/-0.14,0.14/-0.14, 0.05/0.19, 0.05/-0.19,-0.05/0.19,-0.05/-0.19}{\draw (\x,\y) node[color=A1]{\tiny $\bullet$};}
% \foreach \x/\y in {0.37/0.15, 0.37/-0.15,-0.37/0.15,-0.37/-0.15, 0.15/0.37,-0.15/0.37,0.15/-0.37,-0.15/-0.37}{\draw (\x,\y) node[color=C1]{\tiny $\star$};}
 \draw[->] (1.5,0) arc (0:25:1.5);
 \draw (1.5,0) node[above right]{$+$};
\end{tikzpicture}
\end{center}
\begin{corrige}
\begin{colenumerate}{2}
\item $J$ \item $C$ \item $B$ \item $A$ \item $N$ \item $R$ \item $S$ \item $T$ 
\end{colenumerate}
\end{corrige}
\end{exercice*}

