Theorem: MeasureTheory.Measure.ext_of_Iic
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✝¹¹ : TopologicalSpace α✝
inst✝¹⁰ : MeasurableSpace α✝
inst✝⁹ : OpensMeasurableSpace α✝
inst✝⁸ : MeasurableSpace δ
inst✝⁷ : LinearOrder α✝
inst✝⁶ : OrderClosedTopology α✝
a b x : α✝
α : Type u_5
inst✝⁵ : TopologicalSpace α
m : MeasurableSpace α
inst✝⁴ : SecondCountableTopology α
inst✝³ : LinearOrder α
inst✝² : OrderTopology α
inst✝¹ : BorelSpace α
μ ν : Measure α
inst✝ : IsFiniteMeasure μ
h : ∀ (a : α), μ (Iic a) = ν (Iic a)
⊢ μ = ν
state_after: case refine_1
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✝¹¹ : TopologicalSpace α✝
inst✝¹⁰ : MeasurableSpace α✝
inst✝⁹ : OpensMeasurableSpace α✝
inst✝⁸ : MeasurableSpace δ
inst✝⁷ : LinearOrder α✝
inst✝⁶ : OrderClosedTopology α✝
a b x : α✝
α : Type u_5
inst✝⁵ : TopologicalSpace α
m : MeasurableSpace α
inst✝⁴ : SecondCountableTopology α
inst✝³ : LinearOrder α
inst✝² : OrderTopology α
inst✝¹ : BorelSpace α
μ ν : Measure α
inst✝ : IsFiniteMeasure μ
h : ∀ (a : α), μ (Iic a) = ν (Iic a)
⊢ μ univ = ν univ

case refine_2
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✝¹¹ : TopologicalSpace α✝
inst✝¹⁰ : MeasurableSpace α✝
inst✝⁹ : OpensMeasurableSpace α✝
inst✝⁸ : MeasurableSpace δ
inst✝⁷ : LinearOrder α✝
inst✝⁶ : OrderClosedTopology α✝
a✝ b✝ x : α✝
α : Type u_5
inst✝⁵ : TopologicalSpace α
m : MeasurableSpace α
inst✝⁴ : SecondCountableTopology α
inst✝³ : LinearOrder α
inst✝² : OrderTopology α
inst✝¹ : BorelSpace α
μ ν : Measure α
inst✝ : IsFiniteMeasure μ
h : ∀ (a : α), μ (Iic a) = ν (Iic a)
a b : α
hlt : a < b
⊢ μ (Ioc a b) = ν (Ioc a b)
tactic: refine ext_of_Ioc_finite μ ν ?_ fun a b hlt => ?_
state_before: case refine_2
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✝¹¹ : TopologicalSpace α✝
inst✝¹⁰ : MeasurableSpace α✝
inst✝⁹ : OpensMeasurableSpace α✝
inst✝⁸ : MeasurableSpace δ
inst✝⁷ : LinearOrder α✝
inst✝⁶ : OrderClosedTopology α✝
a✝ b✝ x : α✝
α : Type u_5
inst✝⁵ : TopologicalSpace α
m : MeasurableSpace α
inst✝⁴ : SecondCountableTopology α
inst✝³ : LinearOrder α
inst✝² : OrderTopology α
inst✝¹ : BorelSpace α
μ ν : Measure α
inst✝ : IsFiniteMeasure μ
h : ∀ (a : α), μ (Iic a) = ν (Iic a)
a b : α
hlt : a < b
⊢ μ (Ioc a b) = ν (Ioc a b)
state_after: case refine_2
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✝¹¹ : TopologicalSpace α✝
inst✝¹⁰ : MeasurableSpace α✝
inst✝⁹ : OpensMeasurableSpace α✝
inst✝⁸ : MeasurableSpace δ
inst✝⁷ : LinearOrder α✝
inst✝⁶ : OrderClosedTopology α✝
a✝ b✝ x : α✝
α : Type u_5
inst✝⁵ : TopologicalSpace α
m : MeasurableSpace α
inst✝⁴ : SecondCountableTopology α
inst✝³ : LinearOrder α
inst✝² : OrderTopology α
inst✝¹ : BorelSpace α
μ ν : Measure α
inst✝ : IsFiniteMeasure μ
h : ∀ (a : α), μ (Iic a) = ν (Iic a)
a b : α
hlt : a < b
⊢ ν (Iic a) ≠ ⊤

case refine_2
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✝¹¹ : TopologicalSpace α✝
inst✝¹⁰ : MeasurableSpace α✝
inst✝⁹ : OpensMeasurableSpace α✝
inst✝⁸ : MeasurableSpace δ
inst✝⁷ : LinearOrder α✝
inst✝⁶ : OrderClosedTopology α✝
a✝ b✝ x : α✝
α : Type u_5
inst✝⁵ : TopologicalSpace α
m : MeasurableSpace α
inst✝⁴ : SecondCountableTopology α
inst✝³ : LinearOrder α
inst✝² : OrderTopology α
inst✝¹ : BorelSpace α
μ ν : Measure α
inst✝ : IsFiniteMeasure μ
h : ∀ (a : α), μ (Iic a) = ν (Iic a)
a b : α
hlt : a < b
⊢ μ (Iic a) ≠ ⊤
tactic: rw [← Iic_diff_Iic, measure_diff (Iic_subset_Iic.2 hlt.le) measurableSet_Iic,
    measure_diff (Iic_subset_Iic.2 hlt.le) measurableSet_Iic, h a, h b]