Theorem: MeasureTheory.Measure.haar.addCHaar_self
File: Mathlib/MeasureTheory/Measure/Haar/Basic.lean

Proof steps:
state_before: G : Type u_1
inst✝² : Group G
inst✝¹ : TopologicalSpace G
inst✝ : TopologicalGroup G
K₀ : PositiveCompacts G
⊢ chaar K₀ K₀.toCompacts = 1
state_after: G : Type u_1
inst✝² : Group G
inst✝¹ : TopologicalSpace G
inst✝ : TopologicalGroup G
K₀ : PositiveCompacts G
eval : (Compacts G → ℝ) → ℝ := fun f => f K₀.toCompacts
⊢ chaar K₀ K₀.toCompacts = 1
tactic: let eval : (Compacts G → ℝ) → ℝ := fun f => f K₀.toCompacts
state_before: G : Type u_1
inst✝² : Group G
inst✝¹ : TopologicalSpace G
inst✝ : TopologicalGroup G
K₀ : PositiveCompacts G
eval : (Compacts G → ℝ) → ℝ := fun f => f K₀.toCompacts
⊢ chaar K₀ K₀.toCompacts = 1
state_after: G : Type u_1
inst✝² : Group G
inst✝¹ : TopologicalSpace G
inst✝ : TopologicalGroup G
K₀ : PositiveCompacts G
eval : (Compacts G → ℝ) → ℝ := fun f => f K₀.toCompacts
this : Continuous eval
⊢ chaar K₀ K₀.toCompacts = 1
tactic: have : Continuous eval := continuous_apply _
state_before: G : Type u_1
inst✝² : Group G
inst✝¹ : TopologicalSpace G
inst✝ : TopologicalGroup G
K₀ : PositiveCompacts G
eval : (Compacts G → ℝ) → ℝ := fun f => f K₀.toCompacts
this : Continuous eval
⊢ chaar K₀ K₀.toCompacts = 1
state_after: G : Type u_1
inst✝² : Group G
inst✝¹ : TopologicalSpace G
inst✝ : TopologicalGroup G
K₀ : PositiveCompacts G
eval : (Compacts G → ℝ) → ℝ := fun f => f K₀.toCompacts
this : Continuous eval
⊢ chaar K₀ ∈ eval ⁻¹' {1}
tactic: show chaar K₀ ∈ eval ⁻¹' {(1 : ℝ)}
state_before: G : Type u_1
inst✝² : Group G
inst✝¹ : TopologicalSpace G
inst✝ : TopologicalGroup G
K₀ : PositiveCompacts G
eval : (Compacts G → ℝ) → ℝ := fun f => f K₀.toCompacts
this : Continuous eval
⊢ chaar K₀ ∈ eval ⁻¹' {1}
state_after: G : Type u_1
inst✝² : Group G
inst✝¹ : TopologicalSpace G
inst✝ : TopologicalGroup G
K₀ : PositiveCompacts G
eval : (Compacts G → ℝ) → ℝ := fun f => f K₀.toCompacts
this : Continuous eval
⊢ clPrehaar ↑K₀ ⊤ ⊆ eval ⁻¹' {1}
tactic: apply mem_of_subset_of_mem _ (chaar_mem_clPrehaar K₀ ⊤)
state_before: G : Type u_1
inst✝² : Group G
inst✝¹ : TopologicalSpace G
inst✝ : TopologicalGroup G
K₀ : PositiveCompacts G
eval : (Compacts G → ℝ) → ℝ := fun f => f K₀.toCompacts
this : Continuous eval
⊢ clPrehaar ↑K₀ ⊤ ⊆ eval ⁻¹' {1}
state_after: G : Type u_1
inst✝² : Group G
inst✝¹ : TopologicalSpace G
inst✝ : TopologicalGroup G
K₀ : PositiveCompacts G
eval : (Compacts G → ℝ) → ℝ := fun f => f K₀.toCompacts
this : Continuous eval
⊢ closure (prehaar ↑K₀ '' {U | U ⊆ ↑⊤.toOpens ∧ IsOpen U ∧ 1 ∈ U}) ⊆ eval ⁻¹' {1}
tactic: unfold clPrehaar
state_before: G : Type u_1
inst✝² : Group G
inst✝¹ : TopologicalSpace G
inst✝ : TopologicalGroup G
K₀ : PositiveCompacts G
eval : (Compacts G → ℝ) → ℝ := fun f => f K₀.toCompacts
this : Continuous eval
⊢ closure (prehaar ↑K₀ '' {U | U ⊆ ↑⊤.toOpens ∧ IsOpen U ∧ 1 ∈ U}) ⊆ eval ⁻¹' {1}
state_after: G : Type u_1
inst✝² : Group G
inst✝¹ : TopologicalSpace G
inst✝ : TopologicalGroup G
K₀ : PositiveCompacts G
eval : (Compacts G → ℝ) → ℝ := fun f => f K₀.toCompacts
this : Continuous eval
⊢ prehaar ↑K₀ '' {U | U ⊆ ↑⊤.toOpens ∧ IsOpen U ∧ 1 ∈ U} ⊆ eval ⁻¹' {1}

G : Type u_1
inst✝² : Group G
inst✝¹ : TopologicalSpace G
inst✝ : TopologicalGroup G
K₀ : PositiveCompacts G
eval : (Compacts G → ℝ) → ℝ := fun f => f K₀.toCompacts
this : Continuous eval
⊢ IsClosed (eval ⁻¹' {1})
tactic: rw [IsClosed.closure_subset_iff]