Theorem: generateFrom_Ico_mem_le_borel
File: Mathlib/MeasureTheory/Constructions/BorelSpace/Order.lean

Proof steps:
state_before: α✝ : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
ι : Sort y
s✝ t✝ u : Set α✝
inst✝⁸ : TopologicalSpace α✝
inst✝⁷ : MeasurableSpace α✝
inst✝⁶ : OpensMeasurableSpace α✝
inst✝⁵ : MeasurableSpace δ
inst✝⁴ : LinearOrder α✝
inst✝³ : OrderClosedTopology α✝
a b x : α✝
α : Type u_5
inst✝² : TopologicalSpace α
inst✝¹ : LinearOrder α
inst✝ : OrderClosedTopology α
s t : Set α
⊢ MeasurableSpace.generateFrom {S | ∃ l ∈ s, ∃ u ∈ t, l < u ∧ Ico l u = S} ≤ borel α
state_after: case h
α✝ : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
ι : Sort y
s✝ t✝ u : Set α✝
inst✝⁸ : TopologicalSpace α✝
inst✝⁷ : MeasurableSpace α✝
inst✝⁶ : OpensMeasurableSpace α✝
inst✝⁵ : MeasurableSpace δ
inst✝⁴ : LinearOrder α✝
inst✝³ : OrderClosedTopology α✝
a b x : α✝
α : Type u_5
inst✝² : TopologicalSpace α
inst✝¹ : LinearOrder α
inst✝ : OrderClosedTopology α
s t : Set α
⊢ ∀ t_1 ∈ {S | ∃ l ∈ s, ∃ u ∈ t, l < u ∧ Ico l u = S}, MeasurableSet t_1
tactic: apply generateFrom_le
state_before: case h
α✝ : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
ι : Sort y
s✝ t✝ u : Set α✝
inst✝⁸ : TopologicalSpace α✝
inst✝⁷ : MeasurableSpace α✝
inst✝⁶ : OpensMeasurableSpace α✝
inst✝⁵ : MeasurableSpace δ
inst✝⁴ : LinearOrder α✝
inst✝³ : OrderClosedTopology α✝
a b x : α✝
α : Type u_5
inst✝² : TopologicalSpace α
inst✝¹ : LinearOrder α
inst✝ : OrderClosedTopology α
s t : Set α
⊢ ∀ t_1 ∈ {S | ∃ l ∈ s, ∃ u ∈ t, l < u ∧ Ico l u = S}, MeasurableSet t_1
state_after: case h
α✝ : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
ι : Sort y
s✝ t✝ u : Set α✝
inst✝⁸ : TopologicalSpace α✝
inst✝⁷ : MeasurableSpace α✝
inst✝⁶ : OpensMeasurableSpace α✝
inst✝⁵ : MeasurableSpace δ
inst✝⁴ : LinearOrder α✝
inst✝³ : OrderClosedTopology α✝
a b x : α✝
α : Type u_5
inst✝² : TopologicalSpace α
inst✝¹ : LinearOrder α
inst✝ : OrderClosedTopology α
s t : Set α
this✝¹ : MeasurableSpace α := borel α
this✝ : BorelSpace α
⊢ ∀ t_1 ∈ {S | ∃ l ∈ s, ∃ u ∈ t, l < u ∧ Ico l u = S}, MeasurableSet t_1
tactic: borelize α
state_before: case h
α✝ : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
ι : Sort y
s✝ t✝ u : Set α✝
inst✝⁸ : TopologicalSpace α✝
inst✝⁷ : MeasurableSpace α✝
inst✝⁶ : OpensMeasurableSpace α✝
inst✝⁵ : MeasurableSpace δ
inst✝⁴ : LinearOrder α✝
inst✝³ : OrderClosedTopology α✝
a b x : α✝
α : Type u_5
inst✝² : TopologicalSpace α
inst✝¹ : LinearOrder α
inst✝ : OrderClosedTopology α
s t : Set α
this✝¹ : MeasurableSpace α := borel α
this✝ : BorelSpace α
⊢ ∀ t_1 ∈ {S | ∃ l ∈ s, ∃ u ∈ t, l < u ∧ Ico l u = S}, MeasurableSet t_1
state_after: case h.intro.intro.intro.intro.intro
α✝ : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
ι : Sort y
s✝ t✝ u : Set α✝
inst✝⁸ : TopologicalSpace α✝
inst✝⁷ : MeasurableSpace α✝
inst✝⁶ : OpensMeasurableSpace α✝
inst✝⁵ : MeasurableSpace δ
inst✝⁴ : LinearOrder α✝
inst✝³ : OrderClosedTopology α✝
a✝ b✝ x : α✝
α : Type u_5
inst✝² : TopologicalSpace α
inst✝¹ : LinearOrder α
inst✝ : OrderClosedTopology α
s t : Set α
this✝¹ : MeasurableSpace α := borel α
this✝ : BorelSpace α
a b : α
⊢ MeasurableSet (Ico a b)
tactic: rintro _ ⟨a, -, b, -, -, rfl⟩
state_before: case h.intro.intro.intro.intro.intro
α✝ : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
ι : Sort y
s✝ t✝ u : Set α✝
inst✝⁸ : TopologicalSpace α✝
inst✝⁷ : MeasurableSpace α✝
inst✝⁶ : OpensMeasurableSpace α✝
inst✝⁵ : MeasurableSpace δ
inst✝⁴ : LinearOrder α✝
inst✝³ : OrderClosedTopology α✝
a✝ b✝ x : α✝
α : Type u_5
inst✝² : TopologicalSpace α
inst✝¹ : LinearOrder α
inst✝ : OrderClosedTopology α
s t : Set α
this✝¹ : MeasurableSpace α := borel α
this✝ : BorelSpace α
a b : α
⊢ MeasurableSet (Ico a b)
state_after: no goals
tactic: exact measurableSet_Ico