theorem
  |.1q.| = 1
proof
A1: Rea 1q =jj by Lm10,Th16;
A2: Im1 1q = zz by Lm10,Th16;
  Im2 1q = zz by Lm10,Th16;
  hence thesis by A1,A2,Lm10,Th16,SQUARE_1:18;
end;
