proposition: Lemma nbhs0_lt e : 0 < e -> \forall x \near (0 : V), `|x| < e.
proof: Proof. exact: cvgr0_norm_lt. 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