no goals
α : Type u_1
β : Type u_2
inst✝² : TopologicalSpace α
inst✝¹ : PartialOrder α
inst✝ : TopologicalSpace β
a : α
f : α → β
⊢ ContinuousWithinAt f (Ioi a) a ↔ ContinuousWithinAt f (Ici a) a
simp only [← Ici_diff_left, continuousWithinAt_diff_self]