
theorem
  for K be right_zeroed non empty addLoopStr for V,W be non empty
  ModuleStr over K for f be Form of V,W holds f + NulForm(V,W) = f
proof
  let K be right_zeroed non empty addLoopStr, V,W be non empty ModuleStr
  over K, f be Form of V,W;
  set g = NulForm(V,W);
  now
    let v be Vector of V, w be Vector of W;
    thus (f+g).(v,w) = f.(v,w) + g.(v,w) by Def2
      .= f.(v,w) + 0.K by FUNCOP_1:70
      .= f.(v,w) by RLVECT_1:def 4;
  end;
  hence thesis;
end;
