%@Auteur: François Meria\par \begin{enumerate}[(a)] \item \begin{multicols}{2} \begin{itemize} \item [$\circ$] Tracer au centre de la feuille un carré $ABCD$ de $6$~cm de côté ainsi que ses deux diagonales d'intersection $O$. \item [$\circ$] Construire les trois bissectrices du triangle $ABD$. elles se coupent en $I$. \item [$\circ$] Tracer le cercle de centre $I$ et de rayon $IO$. On obtient la figure 1. \end{itemize} \begin{center} \psset{unit=0.6cm} \pspicture(-0.5,-0.5)(6.5,6.5) \pstGeonode[PointSymbol=none,PosAngle={225,-45,45,135}](0,0){D}(6,0){C}(6,6){B}(0,6){A} \pstLineAB{A}{B} \pstLineAB{C}{B} \pstLineAB{A}{D} \pstLineAB{D}{C} \pstLineAB{A}{C} \pstLineAB{D}{B} \pstInterLL[PointSymbol=none,PosAngle=-90]{D}{B}{A}{C}{O} \pstBissectBAC[PointName=none,PointSymbol=none,linestyle=dotted]{A}{B}{D}{M} \pstBissectBAC[PointName=none,PointSymbol=none,linestyle=dotted,nodesepB=2.5]{B}{D}{A}{N} \pstInterLL[PointSymbol=+]{A}{C}{B}{M}{I} \pstCircleOA{I}{O} \put(2,-0.7){Figure 1} \endpspicture \end{center} \end{multicols} \item Compléter cette figure par symétrie par rapport à la droite $(BD)$, faire de même avec la nouvelle figure par rapport à la droite $(BC)$ et enfin par rapport à la droite $(DC)$. \item Colorier la figure avec deux couleurs différentes que l'on alternera afin d'obtenir la figure 2. \end{enumerate} \vskip 1cm \begin{center} \psset{unit=1cm} \pspicture(0,-6)(12,6) %\psgrid \pstGeonode[PointSymbol=none,PointName=none](0,0){D}(6,0){C}(6,6){B}(0,6){A} \pstLineAB{A}{B} \pstLineAB{C}{B} \pstLineAB{A}{D} \pstLineAB{D}{C} \pstLineAB{A}{C} \pstLineAB{D}{B} \pstInterLL[PointSymbol=none,PosAngle=-90,PointName=none]{D}{B}{A}{C}{O} \pstBissectBAC[PointName=none,PointSymbol=none,linestyle=none]{A}{B}{D}{M} \pstBissectBAC[PointName=none,PointSymbol=none,linestyle=none]{B}{D}{A}{N} \pstInterLL[PointSymbol=none,PointName=none]{A}{C}{B}{M}{I} \pstCircleOA{I}{O} \pstOrtSym[PointSymbol=none,PointName=none]{D}{B}{I}{J} \pstCircleOA{J}{O} \pstOrtSym[PointName=none,PointSymbol=none]{B}{C}{D}{E} \pstOrtSym[PointName=none,PointSymbol=none]{B}{C}{A}{F} \pstOrtSym[PointName=none,PointSymbol=none]{B}{C}{I}{K} \pstOrtSym[PointName=none,PointSymbol=none]{B}{C}{J}{L} \pstOrtSym[PointName=none,PointSymbol=none]{B}{C}{O}{O'} \pstCircleOA{K}{O'} \pstCircleOA{L}{O'} \pstLineAB{B}{E} \pstLineAB{B}{F} \pstLineAB{E}{C} \pstLineAB{E}{F} \pstLineAB{C}{F} \pstOrtSym[PointName=none,PointSymbol=none]{D}{C}{A}{Z} \pstOrtSym[PointName=none,PointSymbol=none]{D}{C}{B}{Y} \pstOrtSym[PointName=none,PointSymbol=none]{D}{C}{F}{X} \pstOrtSym[PointName=none,PointSymbol=none]{D}{C}{J}{T} \pstOrtSym[PointName=none,PointSymbol=none]{D}{C}{I}{Q} \pstOrtSym[PointName=none,PointSymbol=none]{D}{C}{O}{P} \pstOrtSym[PointName=none,PointSymbol=none]{D}{C}{O'}{S} \pstOrtSym[PointName=none,PointSymbol=none]{D}{C}{L}{H} \pstOrtSym[PointName=none,PointSymbol=none]{D}{C}{K}{H'} \pstCircleOA{T}{P} \pstCircleOA{H}{S} \pstCircleOA{H'}{S} \pstCircleOA{Q}{P} \pstLineAB{D}{Z} \pstLineAB{C}{Y} \pstLineAB{E}{X} \pstLineAB{E}{F} \pstLineAB{C}{F} \pstLineAB{C}{X} \pstLineAB{Z}{X} \pstLineAB{C}{Z} \pstLineAB{D}{Y} \pstLineAB{Y}{E} \put(5.4,-6.7){Figure 2} \endpspicture \end{center}