Theorem: MeasureTheory.hitting_of_le
File: Mathlib/Probability/Process/HittingTime.lean

tactic: obtain rfl | h := le_iff_eq_or_lt.1 hmn
state_before: Ω : Type u_1
β : Type u_2
ι : Type u_3
m✝ : MeasurableSpace Ω
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
n i : ι
ω : Ω
m : ι
hmn : m ≤ n
⊢ hitting u s n m ω = m
state_after: case inl
Ω : Type u_1
β : Type u_2
ι : Type u_3
m✝ : MeasurableSpace Ω
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
i : ι
ω : Ω
m : ι
hmn : m ≤ m
⊢ hitting u s m m ω = m

case inr
Ω : Type u_1
β : Type u_2
ι : Type u_3
m✝ : MeasurableSpace Ω
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
n i : ι
ω : Ω
m : ι
hmn : m ≤ n
h : m < n
⊢ hitting u s n m ω = m

tactic: rw [hitting, ite_eq_right_iff, forall_exists_index]
state_before: case inl
Ω : Type u_1
β : Type u_2
ι : Type u_3
m✝ : MeasurableSpace Ω
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
i : ι
ω : Ω
m : ι
hmn : m ≤ m
⊢ hitting u s m m ω = m
state_after: case inl
Ω : Type u_1
β : Type u_2
ι : Type u_3
m✝ : MeasurableSpace Ω
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
i : ι
ω : Ω
m : ι
hmn : m ≤ m
⊢ ∀ (x : ι), x ∈ Set.Icc m m ∧ u x ω ∈ s → sInf (Set.Icc m m ∩ {i | u i ω ∈ s}) = m

tactic: conv => intro; rw [Set.mem_Icc, Set.Icc_self, and_imp, and_imp]
state_before: case inl
Ω : Type u_1
β : Type u_2
ι : Type u_3
m✝ : MeasurableSpace Ω
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
i : ι
ω : Ω
m : ι
hmn : m ≤ m
⊢ ∀ (x : ι), x ∈ Set.Icc m m ∧ u x ω ∈ s → sInf (Set.Icc m m ∩ {i | u i ω ∈ s}) = m
state_after: case inl
Ω : Type u_1
β : Type u_2
ι : Type u_3
m✝ : MeasurableSpace Ω
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
i : ι
ω : Ω
m : ι
hmn : m ≤ m
⊢ ∀ (x : ι), m ≤ x → x ≤ m → u x ω ∈ s → sInf ({m} ∩ {i | u i ω ∈ s}) = m

tactic: intro i hi₁ hi₂ hi
state_before: case inl
Ω : Type u_1
β : Type u_2
ι : Type u_3
m✝ : MeasurableSpace Ω
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
i : ι
ω : Ω
m : ι
hmn : m ≤ m
⊢ ∀ (x : ι), m ≤ x → x ≤ m → u x ω ∈ s → sInf ({m} ∩ {i | u i ω ∈ s}) = m
state_after: case inl
Ω : Type u_1
β : Type u_2
ι : Type u_3
m✝ : MeasurableSpace Ω
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
i✝ : ι
ω : Ω
m : ι
hmn : m ≤ m
i : ι
hi₁ : m ≤ i
hi₂ : i ≤ m
hi : u i ω ∈ s
⊢ sInf ({m} ∩ {i | u i ω ∈ s}) = m

tactic: rw [Set.inter_eq_left.2, csInf_singleton]
state_before: case inl
Ω : Type u_1
β : Type u_2
ι : Type u_3
m✝ : MeasurableSpace Ω
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
i✝ : ι
ω : Ω
m : ι
hmn : m ≤ m
i : ι
hi₁ : m ≤ i
hi₂ : i ≤ m
hi : u i ω ∈ s
⊢ sInf ({m} ∩ {i | u i ω ∈ s}) = m
state_after: case inl
Ω : Type u_1
β : Type u_2
ι : Type u_3
m✝ : MeasurableSpace Ω
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
i✝ : ι
ω : Ω
m : ι
hmn : m ≤ m
i : ι
hi₁ : m ≤ i
hi₂ : i ≤ m
hi : u i ω ∈ s
⊢ {m} ⊆ {i | u i ω ∈ s}

tactic: exact Set.singleton_subset_iff.2 (le_antisymm hi₂ hi₁ ▸ hi)
state_before: case inl
Ω : Type u_1
β : Type u_2
ι : Type u_3
m✝ : MeasurableSpace Ω
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
i✝ : ι
ω : Ω
m : ι
hmn : m ≤ m
i : ι
hi₁ : m ≤ i
hi₂ : i ≤ m
hi : u i ω ∈ s
⊢ {m} ⊆ {i | u i ω ∈ s}
state_after: no goals

tactic: exact hitting_of_lt h
state_before: case inr
Ω : Type u_1
β : Type u_2
ι : Type u_3
m✝ : MeasurableSpace Ω
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
n i : ι
ω : Ω
m : ι
hmn : m ≤ n
h : m < n
⊢ hitting u s n m ω = m
state_after: no goals