1  Théorème de Droz-Farny
  2  %@GIAC:
  3  A:=point(0);
  4  B:=point(5);
  5  C:=point(2+4*i);
  6  I:=milieu(B,C);
  7  J:=milieu(C,A);
  8  K:=milieu(A,B);
  9  H:=inter_droite(perpendiculaire(C,droite(A,B)),
 10      perpendiculaire(A,droite(B,C)));
 11  T1:=triangle(A,B,C);
 12  C1:=cercle(H,2);
 13  droite(I,J);droite(J,K);droite(K,I);
 14  PA:=inter(C1,droite(J,K))[0];
 15  QA:=inter(C1,droite(J,K))[1];
 16  SAP:=segment(A,PA);
 17  SAQ:=segment(A,QA);
 18  PB:=inter(C1,droite(K,I))[0];
 19  QB:=inter(C1,droite(K,I))[1];
 20  SBP:=segment(B,PB);
 21  SBQ:=segment(B,QB);
 22  PC:=inter(C1,droite(I,J))[0];
 23  QC:=inter(C1,droite(I,J))[1];
 24  SCP:=segment(C,PC);
 25  SCQ:=segment(C,QC);
 26  %@STYLE:
 27  global: grille=0 v=1 cadre=[-1,-1,6,5] clip=1 unite=1.5cm droite_c=cercle_c=0.5white
 28  T1: e=1 fill=(0.6,0.8,0.6);
 29  I: p=urt
 30  J: p=ulft
 31  A: p=llft
 32  K: p=bot
 33  B: p=lrt
 34  PA: l=P_A
 35  QA: l=Q_A
 36  PB: l=P_B p=rt
 37  QB: l=Q_B p=lrt
 38  PC: l=P_C p=top
 39  QC: l=Q_C p=urt
 40  SAP,SAQ,SBP,SBQ,SCP,SCQ: c=blue
 41  %@EOF: