Ptolemy's Theorem

# AB.CD+BC.DA=AC.BD

Ptolemy:=proc() local A,B,C,D,i,t1,t2,t3,t4,R:

A:=ParamCircle([0,0],R,t1):   B:=ParamCircle([0,0],R,t2):  
C:=ParamCircle([0,0],R,t3):   D:=ParamCircle([0,0],R,t4):  

SumSqRtsIsZero([
DeSq(A,B)*DeSq(C,D),
DeSq(B,C)*DeSq(D,A),
DeSq(A,C)*DeSq(B,D)]):

end:


Previous    Definitions     Theorems     Next