Hugues Vermeiren a réalisé une magnifique présentation pour expliquer les sections de cubes. Nous tenions à vous en faire profiter.
Réalisé avec LaTeX au format BEAMER et utilisant les librairies PGF/TIKZ.
% under Creative Commons attribution license.
% A work by Hugues Vermeiren
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\title{Construction de sections planes}
\subtitle{Cours de 4ème Année \scriptsize{$5\,hrs/sem$}}
\author{Hugues Vermeiren}
\institute[UREM-ULB]{UREM de Bruxelles}
\begin{document}
\frame{\titlepage}
\frame{\tableofcontents}
\section{Sections de Cube}
\begin{frame}
\begin{center}
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%
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\end{center}
\bigskip
\begin{overlayarea}{\textwidth}{8cm}
\begin{center}
\only<1>{Voici un cube!}
\only<2>{$R$ est sur la droite $(KC)$,
$S$ est sur la droite $(BD)$,
$T$ est sur l'arête $[AJ]$.\\
Construire la section du cube par le plan $RST$.
}
\only<3>{La droite $(RS)$ est dans le plan de la face supérieure.\\
Elle coupe donc les arêtes $[BC]$ et $[DK]$ respectivement en $U$ et $V$.
}
\only<4>{La droite $(UT)$ est dans la face $BCJA$...
}
\only<5>{
... et coupe la droite $(AB)$ en $W$.
}
\only<6>{
La droite $SW$ est dans le plan de la face $IABD$.\\
Elle coupe les arêtes $[IA]$, $[ID]$ respectivement en $P$ et $Q$.
}
\only<7-11>{
La section du cube est donc le polygone (plan) $VUTPQ$
}
\only<12>{
C'est un pentagone.\\
Le plan de section coupe toutes les faces du cube sauf la face $OJCK$.
}
\end{center}
\end{overlayarea}
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\end{document}
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