proposition: Lemma C_infty_scal : forall f a, C_infty f -> C_infty (mult_real_fct a f).
proof: Proof. intros f a Cf n ; apply C_scal ; trivial. Qed.
imports: Rbase Ranalysis Lia Lra Rfunctions Rfunction_facts Rextensionality Rinterval Ranalysis_def Ranalysis_def_simpl Ranalysis_facts Ranalysis_continuity Ranalysis_derivability Ranalysis_monotonicity Rfunction_classes_def MyR_dist Reals.Tactics