proposition: Lemma normfZV (x : V) : x != 0 -> `| `|x|^-1 *: x | = 1.
proof: Proof. by rewrite -normr_eq0 -unitfE => /normrZV->. Qed.
imports: HB(structures) mathcomp(all_ssreflect ssralg ssrint ssrnum finmap matrix) mathcomp(rat interval zmodp vector fieldext falgebra) mathcomp(mathcomp_extra boolp classical_sets functions) mathcomp(cardinality set_interval Rstruct) ereal reals signed topology prodnormedzmodule