
theorem
  for K be add-associative right_zeroed right_complementable non empty
addLoopStr  for V,W be non empty ModuleStr over K for f be Form of V,W holds f
  - f = NulForm(V,W)
proof
  let K be add-associative right_zeroed right_complementable non empty
  addLoopStr, V,W be non empty ModuleStr over K, f be Form of V,W;
  now
    let v be Vector of V, w be Vector of W;
    thus (f-f).(v,w) = f.(v,w) - f.(v,w) by Def7
      .= 0.K by RLVECT_1:15
      .= (NulForm(V,W)).(v,w) by FUNCOP_1:70;
  end;
  hence thesis;
end;
