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- window(-1,1,-1,1);
- /*
- The Pythagoras.
-
-
- This construction can be used to proof the Pythagoras theorem.
- From the figure, we get by comparing the areas
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- (a+b)^2=2ab+c^2,
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- which transforms to
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- a^2+b^2=c^2.
-
-
- Move X to see the correctness of this reasoning.
- */
- Point_141()=point(-0.509537,-0.356948);
- Point_142()=point(0.362398,-0.356948);
- Segment_47()=segment(Point_141,Point_142);
- Point_143(hidden),Line_79(hidden)=rectangular(Point_141,Segment_47);
- Point_144(hidden),Line_80(hidden)=rectangular(Point_142,Segment_47);
- Circle_57(hidden)=circle(Point_142,Point_141);
- Cut_78(hidden),Cut_79()=intersection(Line_80,Circle_57);
- Point_147(hidden),Line_81(hidden)=parallel(Cut_79,Segment_47);
- Cut_80()=intersection(Line_79,Line_81);
- Segment_48()=segment(Point_141,Cut_80);
- Segment_49()=segment(Cut_80,Cut_79);
- Segment_50()=segment(Cut_79,Point_142);
- X(showname)=pointon(Segment_47,0.0344828,-0.356948);
- Point_150(hidden),Circle_58(hidden)=circle3(Cut_79,Point_142,X);
- Point_151(hidden),Circle_59(hidden)=circle3(Cut_80,Point_142,X);
- Cut_81(),Cut_82(hidden)=intersection(Circle_59,Segment_49);
- Cut_83(),Cut_84(hidden)=intersection(Circle_58,Segment_50);
- Segment_51()=segment(X,Cut_83);
- Segment_52()=segment(Cut_83,Cut_81);
- Point_156(hidden),Line_87(hidden)=parallel(Cut_81,Segment_51);
- Cut_85()=intersection(Segment_48,Line_87);
- Segment_53()=segment(Cut_81,Cut_85);
- Segment_54()=segment(Cut_85,X);
- a(color:green,showname)=segment(Point_141,X);
- b(color:green,showname)=segment(Point_141,Cut_85);
- c(color:green,showname)=segment(Cut_85,X);
-