reserve A,B for Ordinal,
  K,M,N for Cardinal,
  x,x1,x2,y,y1,y2,z,u for object,X,Y,Z,X1,X2, Y1,Y2 for set,
  f,g for Function;
reserve m,n for Nat;

theorem :: GRAPH_5:1, AK, 21.02.2006
  for f being finite Function holds card rng f <= card dom f
  proof let f be finite Function;
     Segm card rng f c= Segm card dom f by CARD_1:12;
   hence thesis by NAT_1:39;
  end;
