theorem
  for V, W being non empty ModuleStr over INT.Ring, f being Functional of V
    holds
  FormFunctional(f,0Functional(W)) = NulForm(V,W)
  proof
    let V, W be non empty ModuleStr over INT.Ring, f be Functional of V;
    now
      let v be Vector of V, y be Vector of W;
      thus FormFunctional(f,0Functional(W)).(v,y) = 0 by BLTh20
      .= NulForm(V,W).(v,y) by FUNCOP_1:70;
    end;
    hence thesis;
  end;
