theorem Th133:
  for X1, X2 being non empty SubSpace of X st X1 misses X2 for f1
  being continuous Function of X1,Y, f2 being continuous Function of X2,Y holds
  X1,X2 are_weakly_separated implies f1 union f2 is continuous Function of X1
  union X2,Y
proof
  let X1, X2 be non empty SubSpace of X such that
A1: X1 misses X2;
  let f1 be continuous Function of X1,Y, f2 be continuous Function of X2,Y;
  assume
A2: X1,X2 are_weakly_separated;
  (f1 union f2)|X1 = f1 & (f1 union f2)|X2 = f2 by A1,Def12;
  hence thesis by A2,Th114;
end;
