theorem Th34:
  rng f c= Funcs(X,Y) implies rng uncurry f c= Y & rng uncurry' f c= Y
proof
A1: Funcs(X,Y) c= PFuncs(X,Y) by FUNCT_2:72;
  assume rng f c= Funcs(X,Y);
  then rng f c= PFuncs(X,Y) by A1;
  hence thesis by Th33;
end;
