Theorem: Monotone.tendsto_nhdsWithin_Iio
File: Mathlib/Topology/Order/Monotone.lean

Proof steps:
state_before: α✝ : Type u_1
β✝ : Type u_2
γ : Type u_3
inst✝¹² : ConditionallyCompleteLinearOrder α✝
inst✝¹¹ : TopologicalSpace α✝
inst✝¹⁰ : OrderTopology α✝
inst✝⁹ : ConditionallyCompleteLinearOrder β✝
inst✝⁸ : TopologicalSpace β✝
inst✝⁷ : OrderClosedTopology β✝
inst✝⁶ : Nonempty γ
α : Type u_4
β : Type u_5
inst✝⁵ : LinearOrder α
inst✝⁴ : TopologicalSpace α
inst✝³ : OrderTopology α
inst✝² : ConditionallyCompleteLinearOrder β
inst✝¹ : TopologicalSpace β
inst✝ : OrderTopology β
f : α → β
Mf : Monotone f
x : α
⊢ Tendsto f (𝓝[<] x) (𝓝 (sSup (f '' Iio x)))
state_after: case inl
α✝ : Type u_1
β✝ : Type u_2
γ : Type u_3
inst✝¹² : ConditionallyCompleteLinearOrder α✝
inst✝¹¹ : TopologicalSpace α✝
inst✝¹⁰ : OrderTopology α✝
inst✝⁹ : ConditionallyCompleteLinearOrder β✝
inst✝⁸ : TopologicalSpace β✝
inst✝⁷ : OrderClosedTopology β✝
inst✝⁶ : Nonempty γ
α : Type u_4
β : Type u_5
inst✝⁵ : LinearOrder α
inst✝⁴ : TopologicalSpace α
inst✝³ : OrderTopology α
inst✝² : ConditionallyCompleteLinearOrder β
inst✝¹ : TopologicalSpace β
inst✝ : OrderTopology β
f : α → β
Mf : Monotone f
x : α
h : Iio x = ∅
⊢ Tendsto f (𝓝[<] x) (𝓝 (sSup (f '' Iio x)))

case inr
α✝ : Type u_1
β✝ : Type u_2
γ : Type u_3
inst✝¹² : ConditionallyCompleteLinearOrder α✝
inst✝¹¹ : TopologicalSpace α✝
inst✝¹⁰ : OrderTopology α✝
inst✝⁹ : ConditionallyCompleteLinearOrder β✝
inst✝⁸ : TopologicalSpace β✝
inst✝⁷ : OrderClosedTopology β✝
inst✝⁶ : Nonempty γ
α : Type u_4
β : Type u_5
inst✝⁵ : LinearOrder α
inst✝⁴ : TopologicalSpace α
inst✝³ : OrderTopology α
inst✝² : ConditionallyCompleteLinearOrder β
inst✝¹ : TopologicalSpace β
inst✝ : OrderTopology β
f : α → β
Mf : Monotone f
x : α
h : (Iio x).Nonempty
⊢ Tendsto f (𝓝[<] x) (𝓝 (sSup (f '' Iio x)))
tactic: rcases eq_empty_or_nonempty (Iio x) with (h | h)
state_before: case inr
α✝ : Type u_1
β✝ : Type u_2
γ : Type u_3
inst✝¹² : ConditionallyCompleteLinearOrder α✝
inst✝¹¹ : TopologicalSpace α✝
inst✝¹⁰ : OrderTopology α✝
inst✝⁹ : ConditionallyCompleteLinearOrder β✝
inst✝⁸ : TopologicalSpace β✝
inst✝⁷ : OrderClosedTopology β✝
inst✝⁶ : Nonempty γ
α : Type u_4
β : Type u_5
inst✝⁵ : LinearOrder α
inst✝⁴ : TopologicalSpace α
inst✝³ : OrderTopology α
inst✝² : ConditionallyCompleteLinearOrder β
inst✝¹ : TopologicalSpace β
inst✝ : OrderTopology β
f : α → β
Mf : Monotone f
x : α
h : (Iio x).Nonempty
⊢ Tendsto f (𝓝[<] x) (𝓝 (sSup (f '' Iio x)))
state_after: case inr.refine_1
α✝ : Type u_1
β✝ : Type u_2
γ : Type u_3
inst✝¹² : ConditionallyCompleteLinearOrder α✝
inst✝¹¹ : TopologicalSpace α✝
inst✝¹⁰ : OrderTopology α✝
inst✝⁹ : ConditionallyCompleteLinearOrder β✝
inst✝⁸ : TopologicalSpace β✝
inst✝⁷ : OrderClosedTopology β✝
inst✝⁶ : Nonempty γ
α : Type u_4
β : Type u_5
inst✝⁵ : LinearOrder α
inst✝⁴ : TopologicalSpace α
inst✝³ : OrderTopology α
inst✝² : ConditionallyCompleteLinearOrder β
inst✝¹ : TopologicalSpace β
inst✝ : OrderTopology β
f : α → β
Mf : Monotone f
x : α
h : (Iio x).Nonempty
l : β
hl : l < sSup (f '' Iio x)
⊢ ∀ᶠ (b : α) in 𝓝[<] x, l < f b

case inr.refine_2
α✝ : Type u_1
β✝ : Type u_2
γ : Type u_3
inst✝¹² : ConditionallyCompleteLinearOrder α✝
inst✝¹¹ : TopologicalSpace α✝
inst✝¹⁰ : OrderTopology α✝
inst✝⁹ : ConditionallyCompleteLinearOrder β✝
inst✝⁸ : TopologicalSpace β✝
inst✝⁷ : OrderClosedTopology β✝
inst✝⁶ : Nonempty γ
α : Type u_4
β : Type u_5
inst✝⁵ : LinearOrder α
inst✝⁴ : TopologicalSpace α
inst✝³ : OrderTopology α
inst✝² : ConditionallyCompleteLinearOrder β
inst✝¹ : TopologicalSpace β
inst✝ : OrderTopology β
f : α → β
Mf : Monotone f
x : α
h : (Iio x).Nonempty
m : β
hm : m > sSup (f '' Iio x)
⊢ ∀ᶠ (b : α) in 𝓝[<] x, f b < m
tactic: refine tendsto_order.2 ⟨fun l hl => ?_, fun m hm => ?_⟩