proposition: Lemma limg_proj U : limg (projv U) = U.
proof: Proof. apply/vspaceP=> u; apply/memv_imgP/idP=> [[u1 _ ->] | ]; first exact: memv_proj. by exists (projv U u); rewrite ?projv_id ?memv_img ?memvf. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype bigop finfun tuple) mathcomp(ssralg matrix mxalgebra zmodp)