theorem Th56:
  for G being BinContinuous TopaddGroup, A being dense Subset of G,
      a being Point of G holds a+A is dense
proof
  let G be BinContinuous TopaddGroup, A be dense Subset of G, a be Point of G;
  (a+).:A = a+A by Th15;
  hence thesis by TOPGRP_1:28;
end;
