proposition: Lemma Rint_uniqueness : forall f a b x y, Rint f a b x -> Rint f a b y -> x = y.
proof: Proof. intros f a b x y [pr1 H1] [pr2 H2]. rewrite <- H1, <- H2. apply RiemannInt_P5. Qed.
imports: Reals RiemannInt RIneq Lra R_sqr MyRfunctions