proposition: Lemma axAUAw s t u : mprv (AU (s :/\: u) (t :/\: u) ---> AU s t).
proof: Proof. apply: rAU_ind. rewrite -> axAEl. exact: axAUI. rewrite -> axAEl. exact: axAUf. Qed.
imports: mathcomp(all_ssreflect) CompDecModal.libs(edone base fset induced_sym) Setoid Morphisms Relation_Definitions