Theorem: Set.LeftInvOn.map_nhdsWithin_eq
File: Mathlib/Topology/ContinuousOn.lean

tactic: apply le_antisymm
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
inst✝⁴ : TopologicalSpace α
ι : Type u_5
π : ι → Type u_6
inst✝³ : (i : ι) → TopologicalSpace (π i)
inst✝² : TopologicalSpace β
inst✝¹ : TopologicalSpace γ
inst✝ : TopologicalSpace δ
f : α → β
g : β → α
x : β
s : Set β
h : LeftInvOn f g s
hx : f (g x) = x
hf : ContinuousWithinAt f (g '' s) (g x)
hg : ContinuousWithinAt g s x
⊢ map g (𝓝[s] x) = 𝓝[g '' s] g x
state_after: case a
α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
inst✝⁴ : TopologicalSpace α
ι : Type u_5
π : ι → Type u_6
inst✝³ : (i : ι) → TopologicalSpace (π i)
inst✝² : TopologicalSpace β
inst✝¹ : TopologicalSpace γ
inst✝ : TopologicalSpace δ
f : α → β
g : β → α
x : β
s : Set β
h : LeftInvOn f g s
hx : f (g x) = x
hf : ContinuousWithinAt f (g '' s) (g x)
hg : ContinuousWithinAt g s x
⊢ map g (𝓝[s] x) ≤ 𝓝[g '' s] g x

case a
α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
inst✝⁴ : TopologicalSpace α
ι : Type u_5
π : ι → Type u_6
inst✝³ : (i : ι) → TopologicalSpace (π i)
inst✝² : TopologicalSpace β
inst✝¹ : TopologicalSpace γ
inst✝ : TopologicalSpace δ
f : α → β
g : β → α
x : β
s : Set β
h : LeftInvOn f g s
hx : f (g x) = x
hf : ContinuousWithinAt f (g '' s) (g x)
hg : ContinuousWithinAt g s x
⊢ 𝓝[g '' s] g x ≤ map g (𝓝[s] x)

tactic: exact hg.tendsto_nhdsWithin (mapsTo_image _ _)
state_before: case a
α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
inst✝⁴ : TopologicalSpace α
ι : Type u_5
π : ι → Type u_6
inst✝³ : (i : ι) → TopologicalSpace (π i)
inst✝² : TopologicalSpace β
inst✝¹ : TopologicalSpace γ
inst✝ : TopologicalSpace δ
f : α → β
g : β → α
x : β
s : Set β
h : LeftInvOn f g s
hx : f (g x) = x
hf : ContinuousWithinAt f (g '' s) (g x)
hg : ContinuousWithinAt g s x
⊢ map g (𝓝[s] x) ≤ 𝓝[g '' s] g x
state_after: no goals

tactic: have A : g ∘ f =ᶠ[𝓝[g '' s] g x] id :=
  h.rightInvOn_image.eqOn.eventuallyEq_of_mem self_mem_nhdsWithin
state_before: case a
α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
inst✝⁴ : TopologicalSpace α
ι : Type u_5
π : ι → Type u_6
inst✝³ : (i : ι) → TopologicalSpace (π i)
inst✝² : TopologicalSpace β
inst✝¹ : TopologicalSpace γ
inst✝ : TopologicalSpace δ
f : α → β
g : β → α
x : β
s : Set β
h : LeftInvOn f g s
hx : f (g x) = x
hf : ContinuousWithinAt f (g '' s) (g x)
hg : ContinuousWithinAt g s x
⊢ 𝓝[g '' s] g x ≤ map g (𝓝[s] x)
state_after: case a
α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
inst✝⁴ : TopologicalSpace α
ι : Type u_5
π : ι → Type u_6
inst✝³ : (i : ι) → TopologicalSpace (π i)
inst✝² : TopologicalSpace β
inst✝¹ : TopologicalSpace γ
inst✝ : TopologicalSpace δ
f : α → β
g : β → α
x : β
s : Set β
h : LeftInvOn f g s
hx : f (g x) = x
hf : ContinuousWithinAt f (g '' s) (g x)
hg : ContinuousWithinAt g s x
A : g ∘ f =ᶠ[𝓝[g '' s] g x] id
⊢ 𝓝[g '' s] g x ≤ map g (𝓝[s] x)

tactic: refine le_map_of_right_inverse A ?_
state_before: case a
α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
inst✝⁴ : TopologicalSpace α
ι : Type u_5
π : ι → Type u_6
inst✝³ : (i : ι) → TopologicalSpace (π i)
inst✝² : TopologicalSpace β
inst✝¹ : TopologicalSpace γ
inst✝ : TopologicalSpace δ
f : α → β
g : β → α
x : β
s : Set β
h : LeftInvOn f g s
hx : f (g x) = x
hf : ContinuousWithinAt f (g '' s) (g x)
hg : ContinuousWithinAt g s x
A : g ∘ f =ᶠ[𝓝[g '' s] g x] id
⊢ 𝓝[g '' s] g x ≤ map g (𝓝[s] x)
state_after: case a
α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
inst✝⁴ : TopologicalSpace α
ι : Type u_5
π : ι → Type u_6
inst✝³ : (i : ι) → TopologicalSpace (π i)
inst✝² : TopologicalSpace β
inst✝¹ : TopologicalSpace γ
inst✝ : TopologicalSpace δ
f : α → β
g : β → α
x : β
s : Set β
h : LeftInvOn f g s
hx : f (g x) = x
hf : ContinuousWithinAt f (g '' s) (g x)
hg : ContinuousWithinAt g s x
A : g ∘ f =ᶠ[𝓝[g '' s] g x] id
⊢ Tendsto f (𝓝[g '' s] g x) (𝓝[s] x)

tactic: simpa only [hx] using hf.tendsto_nhdsWithin (h.mapsTo (surjOn_image _ _))
state_before: case a
α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
inst✝⁴ : TopologicalSpace α
ι : Type u_5
π : ι → Type u_6
inst✝³ : (i : ι) → TopologicalSpace (π i)
inst✝² : TopologicalSpace β
inst✝¹ : TopologicalSpace γ
inst✝ : TopologicalSpace δ
f : α → β
g : β → α
x : β
s : Set β
h : LeftInvOn f g s
hx : f (g x) = x
hf : ContinuousWithinAt f (g '' s) (g x)
hg : ContinuousWithinAt g s x
A : g ∘ f =ᶠ[𝓝[g '' s] g x] id
⊢ Tendsto f (𝓝[g '' s] g x) (𝓝[s] x)
state_after: no goals