(** Extensionality *)

Lemma RiemannInt_ext : forall (f g : R -> R) (a b : R)
(pr_f : Riemann_integrable f a b) (pr_g : Riemann_integrable g a b)
(Heq : forall x, Rmin a b <= x <= Rmax a b -> f x = g x),
RiemannInt pr_f = RiemannInt pr_g.