
theorem Th10:
  Sq_Circ.(|[-1,0]|)= |[-1,0]|
proof
  set p= |[-1,0]|;
A1: p`1=-1 by EUCLID:52;
A2: p`2=0 by EUCLID:52;
A3: p<>0.TOP-REAL 2 by A1,EUCLID:52,54;
  p`2<=-p`1 by A1,EUCLID:52;
  then Sq_Circ.p= |[p`1/sqrt(1+(p`2/p`1)^2),p`2/sqrt(1+(p`2/p`1)^2)]|
  by A1,A2,A3,JGRAPH_3:def 1;
  hence thesis by A2,EUCLID:52;
end;
