
theorem Th7:
  for L being non empty multMagma, a being Element of L holds (<*>
  the carrier of L)*a = <*>(the carrier of L)
proof
  let L be non empty multMagma, a be Element of L;
  dom((<*>the carrier of L)*a) = dom <*>(the carrier of L) by Def2;
  hence thesis;
end;
