\ANG{
%
%%\item
%
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Gegeben ist ein gleichseitiges Dreieck mit der Seitenl"ange $a$.
(Die Mittelpunkte der Kreisb"ogen sind durch Punkte markiert.)
\begin{enumerate}
\item
Berechnen Sie Fl"ache und Umfang des Umkreises.
\item
Berechnen Sie die Gesamtfl"ache der 3 schraffierten M"ondchen "uber den 
Dreiecksseiten.
\end{enumerate}
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\LSG{   
\begin{enumerate}
\item
$U=2\pi{\sqrt{3} \over 3}a$, $A={\pi \over 3} a^2$
\item
$A_{Monde}={3 \over 8} \pi a^2 + {\sqrt{3} \over 4} a^2 - {\pi \over 3} a^2$
\end{enumerate}     
}
