%@Auteur: Arnaud Gazagnes\par \begin{center} {\psset{unit=1.75cm} \begin{pspicture}(-0.25,-1.15)(2.5,0.55) \rput(1.85,-0.6){$71^{\circ}$} \rput(0.6,-0.1){\textbf{?}} \pstGeonode[PointSymbol=none,PosAngle={240,0,-30}](0,0){O}(2,-1){N}(2.19,0.44){S} \pstLineAB{N}{S} {\psset{unit=0.25cm}\pstSegmentMark[SegmentSymbol=MarkHash]{O}{S} \pstSegmentMark[SegmentSymbol=MarkHash]{O}{N}} {\psset{unit=2.5cm}\pstMarkAngle[]{N}{O}{S}{}} {\psset{unit=1.5cm}\pstMarkAngle[]{S}{N}{O}{}} \end{pspicture}} \kern0.05\linewidth {\psset{unit=3.75cm} \begin{pspicture}(0.875,-0.625)(2,0.125) \rput(1.35,-0.07){$30^{\circ}$} \rput(1.8,-0.3){\textbf{?}} \pstGeonode[PointSymbol=none,PosAngle={240,0,-30}](1,0){E}(1.866,-0.5){T}(2,0){S} \pstLineAB{T}{S} {\psset{unit=0.25cm}\pstSegmentMark[SegmentSymbol=MarkHashh]{E}{S} \pstSegmentMark[SegmentSymbol=MarkHashh]{E}{T}}{\psset{unit=2.5cm}\pstMarkAngle[]{T}{E}{S}{}} {\psset{unit=1.5cm}\pstMarkAngle[]{S}{T}{E}{}} \end{pspicture}} \end{center} \`A l'aide de chacune des figures ci-dessus, calculer les mesures d'angles marqu\'es d'un \og \textbf{?} \fg.