
theorem
  for G being Group for H1, H2 being strict Subgroup of G holds carr G.(
  H1 /\ H2) = carr G.H1 /\ carr G.H2
proof
  let G be Group;
  let H1, H2 be strict Subgroup of G;
  carr G.H1 /\ carr G.H2 = the carrier of H1 /\ H2 by Th18;
  hence thesis by Def1;
end;
