proposition: Lemma continuity_ptE (f : R -> R) (x : R) : continuity_pt f x <-> {for x, continuous f}.
proof: Proof. exact: continuity_pt_cvg. Qed.
imports: Rdefinitions Raxioms RIneq Rbasic_fun Zwf Epsilon FunctionalExtensionality Ranalysis1 Rsqrt_def Rtrigo1 Reals mathcomp(all_ssreflect ssralg poly mxpoly ssrnum) HB(structures) mathcomp(boolp classical_sets) reals signed topology