proposition: Lemma qX_order_card : 'qX ^+ (#|qT|).-1 = 1 :> qT.
proof: Proof. have /primitive_polyP [_ Hd _] := Hh. rewrite dvdp_order in Hd. have -> : 1 = val (1%g : {unit qT}) by []. by rewrite -(eqP Hd) val_unitX. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice fintype tuple) mathcomp(div bigop binomial finset finfun ssralg countalg finalg) mathcomp(poly polydiv qpoly perm fingroup falgebra fieldext finfield galois) mathcomp(finalg zmodp matrix vector)