proposition: Lemma derivable_id (x v : V) : derivable id x v.
proof: Proof. exact/diff_derivable. Qed.
imports: HB(structures) mathcomp(all_ssreflect ssralg ssrnum matrix interval) mathcomp(mathcomp_extra boolp classical_sets functions) reals signed topology prodnormedzmodule normedtype landau forms