reserve X for set,
        n,m,k for Nat,
        K for Field,
        f for n-element real-valued FinSequence,
        M for Matrix of n,m,F_Real;

theorem
  for V be RealLinearSpace,
      F be set
  holds
    F is Subset of V
      iff
    F is Subset of RLSp2RVSp(V);
