proposition: Lemma RNconcave_function f : convex_function (fun x => - f x)%coqR -> concave_function f.
proof: Proof. move=> H a b t; exact/RNconcave_function_at/H. Qed.
imports: HB(structures) mathcomp(all_ssreflect ssralg fingroup perm matrix) mathcomp(mathcomp_extra boolp classical_sets Rstruct) mathcomp(ssrnum ereal) mathcomp(lra Rstruct reals) Reals ssrR Reals_ext Ranalysis_ext ssr_ext ssralg_ext logb realType_ext fdist