proposition: Lemma ex_RInt_norm : forall (f : R -> R) a b, ex_RInt f a b -> ex_RInt (fun x => norm (f x)) a b.
proof: Proof. intros f a b If. apply ex_RInt_Reals_1. apply RiemannInt_P16. now apply ex_RInt_Reals_0. Qed.
imports: Coq(Reals Psatz) mathcomp(ssreflect ssrbool ssrfun eqtype seq) Markov Rcomplements Rbar Lub Lim_seq SF_seq Continuity Hierarchy