proposition: Lemma galV E (x : gal_of E) : {in E, (x^-1)%g =1 x^-1%VF}.
proof: Proof. move=> a Ea; apply: canRL (lker0_lfunK (AEnd_lker0 _)) _. by rewrite -galM // mulVg gal_id. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq div) mathcomp(choice fintype tuple finfun bigop ssralg poly) mathcomp(polydiv finset fingroup morphism quotient perm) mathcomp(action zmodp cyclic matrix mxalgebra vector) mathcomp(falgebra fieldext separable)