α : Type u
β : Type v
γ : Type w
inst✝⁷ : ConditionallyCompleteLinearOrder α
inst✝⁶ : TopologicalSpace α
inst✝⁵ : OrderTopology α
inst✝⁴ : ConditionallyCompleteLinearOrder β
inst✝³ : TopologicalSpace β
inst✝² : OrderTopology β
inst✝¹ : Nonempty γ
inst✝ : DenselyOrdered α
a✝ b✝ a b : α
s : Set α
hs : IsClosed (s ∩ Icc a b)
ha : a ∈ s
hgt : ∀ (x : α), x ∈ s ∩ Ico a b → s ∈ 𝓝[Ioi x] x
⊢ ∀ (x : α), x ∈ s ∩ Ico a b → ∀ (y : α), y ∈ Ioi x → Set.Nonempty (s ∩ Ioc x y)
α : Type u
β : Type v
γ : Type w
inst✝⁷ : ConditionallyCompleteLinearOrder α
inst✝⁶ : TopologicalSpace α
inst✝⁵ : OrderTopology α
inst✝⁴ : ConditionallyCompleteLinearOrder β
inst✝³ : TopologicalSpace β
inst✝² : OrderTopology β
inst✝¹ : Nonempty γ
inst✝ : DenselyOrdered α
a✝ b✝ a b : α
s : Set α
hs : IsClosed (s ∩ Icc a b)
ha : a ∈ s
hgt : ∀ (x : α), x ∈ s ∩ Ico a b → s ∈ 𝓝[Ioi x] x
⊢ Icc a b ⊆ s
apply hs.Icc_subset_of_forall_exists_gt ha
case intro
α : Type u
β : Type v
γ : Type w
inst✝⁷ : ConditionallyCompleteLinearOrder α
inst✝⁶ : TopologicalSpace α
inst✝⁵ : OrderTopology α
inst✝⁴ : ConditionallyCompleteLinearOrder β
inst✝³ : TopologicalSpace β
inst✝² : OrderTopology β
inst✝¹ : Nonempty γ
inst✝ : DenselyOrdered α
a✝ b✝ a b : α
s : Set α
hs : IsClosed (s ∩ Icc a b)
ha : a ∈ s
hgt : ∀ (x : α), x ∈ s ∩ Ico a b → s ∈ 𝓝[Ioi x] x
x : α
hxs : x ∈ s
hxab : x ∈ Ico a b
y : α
hyxb : y ∈ Ioi x
⊢ Set.Nonempty (s ∩ Ioc x y)
α : Type u
β : Type v
γ : Type w
inst✝⁷ : ConditionallyCompleteLinearOrder α
inst✝⁶ : TopologicalSpace α
inst✝⁵ : OrderTopology α
inst✝⁴ : ConditionallyCompleteLinearOrder β
inst✝³ : TopologicalSpace β
inst✝² : OrderTopology β
inst✝¹ : Nonempty γ
inst✝ : DenselyOrdered α
a✝ b✝ a b : α
s : Set α
hs : IsClosed (s ∩ Icc a b)
ha : a ∈ s
hgt : ∀ (x : α), x ∈ s ∩ Ico a b → s ∈ 𝓝[Ioi x] x
⊢ ∀ (x : α), x ∈ s ∩ Ico a b → ∀ (y : α), y ∈ Ioi x → Set.Nonempty (s ∩ Ioc x y)
rintro x ⟨hxs, hxab⟩ y hyxb
case intro
α : Type u
β : Type v
γ : Type w
inst✝⁷ : ConditionallyCompleteLinearOrder α
inst✝⁶ : TopologicalSpace α
inst✝⁵ : OrderTopology α
inst✝⁴ : ConditionallyCompleteLinearOrder β
inst✝³ : TopologicalSpace β
inst✝² : OrderTopology β
inst✝¹ : Nonempty γ
inst✝ : DenselyOrdered α
a✝ b✝ a b : α
s : Set α
hs : IsClosed (s ∩ Icc a b)
ha : a ∈ s
hgt : ∀ (x : α), x ∈ s ∩ Ico a b → s ∈ 𝓝[Ioi x] x
x : α
hxs : x ∈ s
hxab : x ∈ Ico a b
y : α
hyxb : y ∈ Ioi x
this : s ∩ Ioc x y ∈ 𝓝[Ioi x] x
⊢ Set.Nonempty (s ∩ Ioc x y)
case intro
α : Type u
β : Type v
γ : Type w
inst✝⁷ : ConditionallyCompleteLinearOrder α
inst✝⁶ : TopologicalSpace α
inst✝⁵ : OrderTopology α
inst✝⁴ : ConditionallyCompleteLinearOrder β
inst✝³ : TopologicalSpace β
inst✝² : OrderTopology β
inst✝¹ : Nonempty γ
inst✝ : DenselyOrdered α
a✝ b✝ a b : α
s : Set α
hs : IsClosed (s ∩ Icc a b)
ha : a ∈ s
hgt : ∀ (x : α), x ∈ s ∩ Ico a b → s ∈ 𝓝[Ioi x] x
x : α
hxs : x ∈ s
hxab : x ∈ Ico a b
y : α
hyxb : y ∈ Ioi x
⊢ Set.Nonempty (s ∩ Ioc x y)
have : s ∩ Ioc x y ∈ 𝓝[>] x :=
  inter_mem (hgt x ⟨hxs, hxab⟩) (Ioc_mem_nhdsWithin_Ioi ⟨le_rfl, hyxb⟩)
no goals
case intro
α : Type u
β : Type v
γ : Type w
inst✝⁷ : ConditionallyCompleteLinearOrder α
inst✝⁶ : TopologicalSpace α
inst✝⁵ : OrderTopology α
inst✝⁴ : ConditionallyCompleteLinearOrder β
inst✝³ : TopologicalSpace β
inst✝² : OrderTopology β
inst✝¹ : Nonempty γ
inst✝ : DenselyOrdered α
a✝ b✝ a b : α
s : Set α
hs : IsClosed (s ∩ Icc a b)
ha : a ∈ s
hgt : ∀ (x : α), x ∈ s ∩ Ico a b → s ∈ 𝓝[Ioi x] x
x : α
hxs : x ∈ s
hxab : x ∈ Ico a b
y : α
hyxb : y ∈ Ioi x
this : s ∩ Ioc x y ∈ 𝓝[Ioi x] x
⊢ Set.Nonempty (s ∩ Ioc x y)
exact (nhdsWithin_Ioi_self_neBot' ⟨b, hxab.2⟩).nonempty_of_mem this