α : Type u_1
inst✝⁴ : TopologicalSpace α
β : Type ?u.227746
inst✝³ : Preorder β
f✝ g : α → β
x : α
s t : Set α
y z : β
γ : Type u_2
inst✝² : LinearOrder γ
inst✝¹ : TopologicalSpace γ
inst✝ : OrderTopology γ
f : α → γ
⊢ (∀ (x : α), x ∈ s → LowerSemicontinuousWithinAt f s x ∧ UpperSemicontinuousWithinAt f s x) ↔
    LowerSemicontinuousOn f s ∧ UpperSemicontinuousOn f s
α : Type u_1
inst✝⁴ : TopologicalSpace α
β : Type ?u.227746
inst✝³ : Preorder β
f✝ g : α → β
x : α
s t : Set α
y z : β
γ : Type u_2
inst✝² : LinearOrder γ
inst✝¹ : TopologicalSpace γ
inst✝ : OrderTopology γ
f : α → γ
⊢ ContinuousOn f s ↔ LowerSemicontinuousOn f s ∧ UpperSemicontinuousOn f s
simp only [ContinuousOn, continuousWithinAt_iff_lower_upperSemicontinuousWithinAt]
no goals
α : Type u_1
inst✝⁴ : TopologicalSpace α
β : Type ?u.227746
inst✝³ : Preorder β
f✝ g : α → β
x : α
s t : Set α
y z : β
γ : Type u_2
inst✝² : LinearOrder γ
inst✝¹ : TopologicalSpace γ
inst✝ : OrderTopology γ
f : α → γ
⊢ (∀ (x : α), x ∈ s → LowerSemicontinuousWithinAt f s x ∧ UpperSemicontinuousWithinAt f s x) ↔
    LowerSemicontinuousOn f s ∧ UpperSemicontinuousOn f s
exact
  ⟨fun H => ⟨fun x hx => (H x hx).1, fun x hx => (H x hx).2⟩, fun H x hx => ⟨H.1 x hx, H.2 x hx⟩⟩