proposition: Lemma normalClosureSl E F : (E <= normalClosure E F)%VS.
proof: Proof. by rewrite (subv_trans (field_subvMr _ _) (prodv_sub_normalClosure _ _)). Qed.
imports: HB(structures) mathcomp(all_ssreflect all_fingroup all_algebra) mathcomp(all_solvable all_field) Abel(various char0)