no goals
α : Type u_1
β : Type u_2
γ : Type ?u.325137
δ : Type ?u.325140
inst✝³ : TopologicalSpace α
inst✝² : TopologicalSpace β
inst✝¹ : TopologicalSpace γ
inst✝ : TopologicalSpace δ
f : α → β
x : α
⊢ ContinuousWithinAt f {x} x
simp only [ContinuousWithinAt, nhdsWithin_singleton, tendsto_pure_nhds]