proposition: Lemma derive1n1 V (f : R -> V) : f^`(1) = f^`().
proof: Proof. by []. 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