proposition: Lemma Pr_inter_eq E1 E2 : Pr (E1 :&: E2) = Pr E1 + Pr E2 - Pr (E1 :|: E2).
proof: Proof. by rewrite Pr_union_eq subRBA addRC addRK. 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