proposition: Lemma scalel_RVA k l X : scalel_RV (k * l) X = scalel_RV k (scalel_RV l X).
proof: Proof. by rewrite /scalel_RV boolp.funeqE => u; rewrite mulRA. Qed.
imports: mathcomp(all_ssreflect ssralg ssrnum matrix) mathcomp(Rstruct reals) Reals Lra ssrR Reals_ext realType_ext logb ssr_ext ssralg_ext bigop_ext fdist