mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Topology.Connected.Basic

Goal state before:
pp: α : Type u
inst✝ : TopologicalSpace α
x : α
F : Set α
⊢ IsPreconnected (if h : x ∈ F then Subtype.val '' connectedComponent ⟨x, h⟩ else ∅)

Tactic:
split_ifs

Goal state after:
case pos
α : Type u
inst✝ : TopologicalSpace α
x : α
F : Set α
h✝ : x ∈ F
⊢ IsPreconnected (Subtype.val '' connectedComponent ⟨x, h✝⟩)

case neg
α : Type u
inst✝ : TopologicalSpace α
x : α
F : Set α
h✝ : x ∉ F
⊢ IsPreconnected ∅
Module: Mathlib.Topology.Connected.Clopen

Goal state before:
pp: case refine_1
α : Type u
inst✝ : TopologicalSpace α
s : Set α
hs : IsClopen s
⊢ IsPreconnected s → ∀ (a b : Set α), IsClopen a → IsClopen b → a.Nonempty → b.Nonempty → Disjoint a b → s ≠ a ∪ b

Tactic:
contrapose!
    rintro ⟨a, b, ha, hb, ha', hb', hab, rfl⟩ H
    exact (H a b ha.isOpen hb.isOpen subset_rfl (by rwa [union_inter_cancel_left])
      (by rwa [union_inter_cancel_right])).ne_empty (by grind)

Goal state after:
Module: Mathlib.Topology.Connected.Basic

Goal state before:
pp: case mpr.inl
α : Type u
inst✝ : TopologicalSpace α
h : ∀ (x : α), connectedComponent x = univ
hα : IsEmpty α
⊢ PreconnectedSpace α

Tactic:
exact ⟨by rw [univ_eq_empty_iff.mpr hα]; exact isPreconnected_empty⟩

Goal state after:
Module: Mathlib.Topology.Separation.Regular

Goal state before:
pp: case refine_2
X : Type u_1
inst✝ : TopologicalSpace X
s t : Set X
hSt : Disjoint (closure[inst✝] s) t
hsT : Disjoint s (closure[inst✝] t)
e : Set X := (closure[inst✝] s ∩ closure[inst✝] t)ᶜ
h : NormalSpace ↑e
he : IsOpen[inst✝] e
hst : Disjoint (Subtype.val ⁻¹' closure[inst✝] s) (Subtype.val ⁻¹' closure[inst✝] t)
U : Set X
hU : IsOpen[inst✝] U
hsU : closure[inst✝] s ∩ e ⊆ U ∩ e
V : Set X
hV : IsOpen[inst✝] V
htV : closure[inst✝] t ∩ e ⊆ V ∩ e
hUV : Disjoint (Subtype.val ⁻¹' U) (Subtype.val ⁻¹' V)
x : X
hx : x ∈ t
⊢ x ∈ V ∩ e

Tactic:
exact htV ⟨subset_closure hx, fun h => hSt.notMem_of_mem_left h.1 hx⟩

Goal state after:
Module: Mathlib.Topology.DenseEmbedding

Goal state before:
pp: α : Type u_1
β : Type u_2
γ : Type u_3
inst✝³ : TopologicalSpace α
inst✝² : TopologicalSpace β
i : α → β
inst✝¹ : TopologicalSpace γ
inst✝ : T3Space γ
b : β
f : α → γ
di : IsDenseInducing i
hf : ∀ᶠ (x : β) in 𝓝 b, ∃ c, Tendsto f (comap i (𝓝 x)) (𝓝 c)
φ : β → γ := di.extend f
this : ∀ (b : β), (comap i (𝓝 b)).NeBot
V' : Set γ
V'_in : V' ∈ 𝓝 (φ b)
V'_closed : IsClosed[inst✝¹] V'
V₁ : Set β := {x | Tendsto f (comap i (𝓝 x)) (𝓝 (φ x))}
V₁_in : V₁ ∈ 𝓝 b
V₂ : Set β
V₂_in : V₂ ∈ 𝓝 b
V₂_op : IsOpen[inst✝²] V₂
hV₂ : ∀ x ∈ i ⁻¹' V₂, f x ∈ V'
⊢ φ ⁻¹' V' ∈ 𝓝 b

Tactic:
suffices ∀ x ∈ V₁ ∩ V₂, φ x ∈ V' by filter_upwards [inter_mem V₁_in V₂_in] using this

Goal state after:
α : Type u_1
β : Type u_2
γ : Type u_3
inst✝³ : TopologicalSpace α
inst✝² : TopologicalSpace β
i : α → β
inst✝¹ : TopologicalSpace γ
inst✝ : T3Space γ
b : β
f : α → γ
di : IsDenseInducing i
hf : ∀ᶠ (x : β) in 𝓝 b, ∃ c, Tendsto f (comap i (𝓝 x)) (𝓝 c)
φ : β → γ := di.extend f
this : ∀ (b : β), (comap i (𝓝 b)).NeBot
V' : Set γ
V'_in : V' ∈ 𝓝 (φ b)
V'_closed : IsClosed[inst✝¹] V'
V₁ : Set β := {x | Tendsto f (comap i (𝓝 x)) (𝓝 (φ x))}
V₁_in : V₁ ∈ 𝓝 b
V₂ : Set β
V₂_in : V₂ ∈ 𝓝 b
V₂_op : IsOpen[inst✝²] V₂
hV₂ : ∀ x ∈ i ⁻¹' V₂, f x ∈ V'
⊢ ∀ x ∈ V₁ ∩ V₂, φ x ∈ V'
Module: Mathlib.Topology.Compactness.Lindelof

Goal state before:
pp: X : Type u
Y : Type v
ι : Type u_1
inst✝² : TopologicalSpace X
inst✝¹ : TopologicalSpace Y
s t : Set X
r : X → X → Prop
inst✝ : LindelofSpace X
⊢ IsLindelof univ

Tactic:
rw [← range_quot_mk]

Goal state after:
X : Type u
Y : Type v
ι : Type u_1
inst✝² : TopologicalSpace X
inst✝¹ : TopologicalSpace Y
s t : Set X
r : X → X → Prop
inst✝ : LindelofSpace X
⊢ IsLindelof (range (mk r))
Module: Mathlib.Topology.GDelta.Basic

Goal state before:
pp: case refine_2
X : Type u_1
inst✝ : TopologicalSpace X
s : Set X
⊢ (∃ f, (∀ (n : ℕ), IsOpen[inst✝] (f n)) ∧ s = ⋂ n, f n) → IsGδ s

Tactic:
· rintro ⟨f, hf, rfl⟩
    exact .iInter_of_isOpen hf

Goal state after:
Module: Mathlib.Topology.Baire.Lemmas

Goal state before:
pp: X : Type u_1
inst✝² : TopologicalSpace X
inst✝¹ : BaireSpace X
Y : Type u_4
inst✝ : TopologicalSpace Y
f : X → Y
hf : IsOpenQuotientMap f
⊢ BaireSpace Y

Tactic:
constructor
  intro u hou hdu
  have := dense_iInter_of_isOpen_nat (fun n => hf.continuous.isOpen_preimage (u n) (hou n))
    (fun n => (IsOpenQuotientMap.dense_preimage_iff hf).mpr (hdu n))
  simp_all [← preimage_iInter, IsOpenQuotientMap.dense_preimage_iff]

Goal state after:
Module: Mathlib.Topology.Homeomorph.Lemmas

Goal state before:
pp: X : Type u_1
Y✝ : Type u_2
W : Type u_3
Z : Type u_4
inst✝⁷ : TopologicalSpace X
inst✝⁶ : TopologicalSpace Y✝
inst✝⁵ : TopologicalSpace W
inst✝⁴ : TopologicalSpace Z
X' : Type u_5
Y' : Type u_6
inst✝³ : TopologicalSpace X'
inst✝² : TopologicalSpace Y'
ι : Type u_7
p : ι → Prop
Y : ι → Type u_8
inst✝¹ : (i : ι) → TopologicalSpace (Y i)
inst✝ : DecidablePred p
j : ι
⊢ Continuous[instTopologicalSpaceProd, inst✝¹ j] fun a ↦ if h : p j then a.1 ⟨j, h⟩ else a.2 ⟨j, h⟩

Tactic:
split_ifs

Goal state after:
case pos
X : Type u_1
Y✝ : Type u_2
W : Type u_3
Z : Type u_4
inst✝⁷ : TopologicalSpace X
inst✝⁶ : TopologicalSpace Y✝
inst✝⁵ : TopologicalSpace W
inst✝⁴ : TopologicalSpace Z
X' : Type u_5
Y' : Type u_6
inst✝³ : TopologicalSpace X'
inst✝² : TopologicalSpace Y'
ι : Type u_7
p : ι → Prop
Y : ι → Type u_8
inst✝¹ : (i : ι) → TopologicalSpace (Y i)
inst✝ : DecidablePred p
j : ι
h✝ : p j
⊢ Continuous[instTopologicalSpaceProd, inst✝¹ j] fun a ↦ a.1 ⟨j, h✝⟩

case neg
X : Type u_1
Y✝ : Type u_2
W : Type u_3
Z : Type u_4
inst✝⁷ : TopologicalSpace X
inst✝⁶ : TopologicalSpace Y✝
inst✝⁵ : TopologicalSpace W
inst✝⁴ : TopologicalSpace Z
X' : Type u_5
Y' : Type u_6
inst✝³ : TopologicalSpace X'
inst✝² : TopologicalSpace Y'
ι : Type u_7
p : ι → Prop
Y : ι → Type u_8
inst✝¹ : (i : ι) → TopologicalSpace (Y i)
inst✝ : DecidablePred p
j : ι
h✝ : ¬p j
⊢ Continuous[instTopologicalSpaceProd, inst✝¹ j] fun a ↦ a.2 ⟨j, h✝⟩
Module: Mathlib.Topology.UniformSpace.Defs

Goal state before:

Tactic:
t ○ t ○ t ⊆ w ○ (t ○ t) := by gcongr
    _ ⊆ w ○ w := by gcongr
    _ ⊆ s := w_sub

Goal state after:
Module: Mathlib.Topology.UniformSpace.Cauchy

Goal state before:
pp: case refine_2
α : Type u
uniformSpace : UniformSpace α
f : Filter α
hf : f.TotallyBounded
s : Set α
hs : s ∈ f
U : SetRel α α
hU : U ∈ 𝓤 α
r : Set (α × α)
hr : r ∈ 𝓤 α
rs : ∀ {a b : α}, (a, b) ∈ r → (b, a) ∈ r
rU : r ○ r ⊆ U
k : Set α
fk : k.Finite
ks : SetRel.preimage r k ∈ f
u : Set α := k ∩ {y | ∃ x ∈ s, (x, y) ∈ r}
g : ↑u → α
hgs : ∀ (x : ↑u), g x ∈ s
hgr : ∀ (x : ↑u), (g x, ↑x) ∈ r
⊢ (range g).Finite

pp: case refine_3
α : Type u
uniformSpace : UniformSpace α
f : Filter α
hf : f.TotallyBounded
s : Set α
hs : s ∈ f
U : SetRel α α
hU : U ∈ 𝓤 α
r : Set (α × α)
hr : r ∈ 𝓤 α
rs : ∀ {a b : α}, (a, b) ∈ r → (b, a) ∈ r
rU : r ○ r ⊆ U
k : Set α
fk : k.Finite
ks : SetRel.preimage r k ∈ f
u : Set α := k ∩ {y | ∃ x ∈ s, (x, y) ∈ r}
g : ↑u → α
hgs : ∀ (x : ↑u), g x ∈ s
hgr : ∀ (x : ↑u), (g x, ↑x) ∈ r
⊢ U.preimage (range g) ∈ f

Tactic:
· have : Fintype u := (fk.inter_of_left _).fintype
    exact finite_range g

Goal state after:
case refine_3
α : Type u
uniformSpace : UniformSpace α
f : Filter α
hf : f.TotallyBounded
s : Set α
hs : s ∈ f
U : SetRel α α
hU : U ∈ 𝓤 α
r : Set (α × α)
hr : r ∈ 𝓤 α
rs : ∀ {a b : α}, (a, b) ∈ r → (b, a) ∈ r
rU : r ○ r ⊆ U
k : Set α
fk : k.Finite
ks : SetRel.preimage r k ∈ f
u : Set α := k ∩ {y | ∃ x ∈ s, (x, y) ∈ r}
g : ↑u → α
hgs : ∀ (x : ↑u), g x ∈ s
hgr : ∀ (x : ↑u), (g x, ↑x) ∈ r
⊢ U.preimage (range g) ∈ f
Module: Mathlib.Topology.UniformSpace.UniformConvergence

Goal state before:
pp: α : Type u_1
β : Type u_2
ι : Type u_4
inst✝ : UniformSpace β
F : ι → α → β
f : α → β
p : Filter ι
p' : Filter α
hF : TendstoUniformlyOnFilter F f p p'
⊢ UniformCauchySeqOnFilter F p p'

Tactic:
intro u hu
  rcases comp_symm_of_uniformity hu with ⟨t, ht, htsymm, htmem⟩
  have := tendsto_swap4_prod.eventually ((hF t ht).prod_mk (hF t ht))
  apply this.diag_of_prod_right.mono
  simp only [and_imp, Prod.forall]
  intro n1 n2 x hl hr
  exact htmem <| SetRel.prodMk_mem_comp (htsymm hl) hr

Goal state after:
Module: Mathlib.Topology.UniformSpace.UniformEmbedding

Goal state before:
pp: α : Type u
β : Type v
inst✝¹ : UniformSpace α
inst✝ : UniformSpace β
f : α → β
⊢ IsUniformInducing f ↔ UniformSpace.comap f inst✝ = inst✝¹

Tactic:
rw [isUniformInducing_iff, UniformSpace.ext_iff, Filter.ext_iff]
  rfl

Goal state after:
Module: Mathlib.Topology.UniformSpace.UniformEmbedding

Goal state before:
pp: α : Type u_1
β : Type u_2
γ : Type u_3
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
inst✝¹ : UniformSpace γ
e : β → α
h_e : IsUniformInducing e
h_dense : DenseRange e
f : β → γ
h_f : UniformContinuous f
inst✝ : CompleteSpace γ
d : Set (γ × γ)
hd : d ∈ 𝓤 γ
s : Set (γ × γ)
hs : s ∈ 𝓤 γ
hs_comp : s ○ (s ○ s) ⊆ d
h_pnt : ∀ {a : α} {m : Set α}, m ∈ 𝓝 a → ∃ c ∈ f '' e ⁻¹' m, (c, ⋯.extend f a) ∈ s ∧ (⋯.extend f a, c) ∈ s
this✝ : Prod.map f f ⁻¹' s ∈ 𝓤 β
this : Prod.map f f ⁻¹' s ∈ comap (Prod.map e e) (𝓤 α)
t : Set (α × α)
ht : t ∈ 𝓤 α
ts : Prod.map e e ⁻¹' t ⊆ Prod.map f f ⁻¹' s
x✝ : α × α
x₁ x₂ : α
hx_t : (x₁, x₂) ∈ interior t
⊢ (x₁, x₂) ∈ Prod.map (⋯.extend f) (⋯.extend f) ⁻¹' d

Tactic:
have : interior t ∈ 𝓝 (x₁, x₂) := isOpen_interior.mem_nhds hx_t
      let ⟨m₁, hm₁, m₂, hm₂, (hm : m₁ ×ˢ m₂ ⊆ interior t)⟩ := mem_nhds_prod_iff.mp this
      obtain ⟨_, ⟨a, ha₁, rfl⟩, _, ha₂⟩ := h_pnt hm₁
      obtain ⟨_, ⟨b, hb₁, rfl⟩, hb₂, _⟩ := h_pnt hm₂
      have : Prod.map f f (a, b) ∈ s :=
        ts <| mem_preimage.2 <| interior_subset (@hm (e a, e b) ⟨ha₁, hb₁⟩)
      exact hs_comp ⟨f a, ha₂, ⟨f b, this, hb₂⟩⟩

Goal state after:
Module: Mathlib.Topology.Algebra.Support

Goal state before:
pp: α : Type u_2
γ : Type u_5
inst✝² : TopologicalSpace α
inst✝¹ : One γ
f : α → γ
inst✝ : TopologicalSpace γ
h : HasCompactMulSupport f
⊢ Tendsto f (cocompact α) (𝓝 1)

Tactic:
intro N hN

Goal state after:
α : Type u_2
γ : Type u_5
inst✝² : TopologicalSpace α
inst✝¹ : One γ
f : α → γ
inst✝ : TopologicalSpace γ
h : HasCompactMulSupport f
N : Set γ
hN : N ∈ 𝓝 1
⊢ N ∈ map f (cocompact α)
Module: Mathlib.Topology.Algebra.Support

Goal state before:
pp: X : Type u_1
R : Type u_8
ι : Type u_9
inst✝¹ : TopologicalSpace X
U : ι → Set X
inst✝ : One R
f : ι → X → R
hlf : LocallyFinite fun i ↦ mulSupport (f i)
hso : ∀ (i : ι), mulTSupport (f i) ⊆ U i
ho : ∀ (i : ι), IsOpen[inst✝¹] (U i)
x : X
n : Set X
hn : n ∈ 𝓝 x
hnf : {i | ((fun i ↦ mulSupport (f i)) i ∩ n).Nonempty}.Finite
is : Finset ι := {i ∈ hnf.toFinset | x ∈ U i}
js : Finset ι := {j ∈ hnf.toFinset | x ∉ U j}
z : X
hzn : z ∈ n
this : (mulSupport fun i ↦ f i z) ⊆ ↑hnf.toFinset
i : ι
hi : i ∈ mulSupport fun i ↦ f i z
hz : x ∉ U i
⊢ ¬(x ∉ U i → z ∈ (mulTSupport (f i))ᶜ)

Tactic:
simp [hz, subset_mulTSupport (f i) hi]

Goal state after:
Module: Mathlib.Topology.UniformSpace.LocallyUniformConvergence

Goal state before:
pp: α : Type u_1
β : Type u_2
γ : Type u_3
ι : Type u_4
inst✝² : TopologicalSpace α
inst✝¹ : UniformSpace β
F : ι → α → β
f : α → β
s : Set α
p : Filter ι
inst✝ : TopologicalSpace γ
t : Set γ
h : TendstoLocallyUniformlyOn F f p s
g : γ → α
hg : MapsTo g t s
cg : ContinuousOn g t
u : Set (β × β)
hu : u ∈ 𝓤 β
x : γ
hx : x ∈ t
a : Set α
ha : a ∈ 𝓝[s] g x
H : ∀ᶠ (n : ι) in p, ∀ y ∈ a, (f y, F n y) ∈ u
⊢ ∃ t_1 ∈ 𝓝[t] x, ∀ᶠ (n : ι) in p, ∀ y ∈ t_1, ((f ∘ g) y, (fun n ↦ F n ∘ g) n y) ∈ u

Tactic:
have : g ⁻¹' a ∈ 𝓝[t] x :=
    (cg x hx).preimage_mem_nhdsWithin' (nhdsWithin_mono (g x) hg.image_subset ha)

Goal state after:
α : Type u_1
β : Type u_2
γ : Type u_3
ι : Type u_4
inst✝² : TopologicalSpace α
inst✝¹ : UniformSpace β
F : ι → α → β
f : α → β
s : Set α
p : Filter ι
inst✝ : TopologicalSpace γ
t : Set γ
h : TendstoLocallyUniformlyOn F f p s
g : γ → α
hg : MapsTo g t s
cg : ContinuousOn g t
u : Set (β × β)
hu : u ∈ 𝓤 β
x : γ
hx : x ∈ t
a : Set α
ha : a ∈ 𝓝[s] g x
H : ∀ᶠ (n : ι) in p, ∀ y ∈ a, (f y, F n y) ∈ u
this : g ⁻¹' a ∈ 𝓝[t] x
⊢ ∃ t_1 ∈ 𝓝[t] x, ∀ᶠ (n : ι) in p, ∀ y ∈ t_1, ((f ∘ g) y, (fun n ↦ F n ∘ g) n y) ∈ u
Module: Mathlib.Topology.UniformSpace.HeineCantor

Goal state before:
pp: case hmono
α : Type u_4
β : Type u_5
E : Type u_6
inst✝² : TopologicalSpace α
inst✝¹ : TopologicalSpace β
inst✝ : UniformSpace E
f : α → β → E
s : Set α
k : Set β
q : α
u : Set (E × E)
hk : IsCompact k
hf : ContinuousOn (Function.uncurry f) (s ×ˢ k)
hq : q ∈ s
hu : u ∈ 𝓤 E
t' t : Set β
ht't : t' ⊆ t
v : Set α
v_mem : v ∈ 𝓝[s] q
hv : ∀ p ∈ v, ∀ x ∈ t, (f p x, f q x) ∈ u
⊢ ∃ v ∈ 𝓝[s] q, ∀ p ∈ v, ∀ x ∈ t', (f p x, f q x) ∈ u

Tactic:
exact ⟨v, v_mem, fun p hp x hx ↦ hv p hp x (ht't hx)⟩

Goal state after:
Module: Mathlib.Topology.UniformSpace.UniformConvergenceTopology

Goal state before:
pp: α : Type u_1
β : Type u_2
γ : Type u_3
ι : Type u_4
p : Filter ι
inst✝¹ : UniformSpace β
inst✝ : UniformSpace γ
⊢ comap
      (Prod.map ⇑(Equiv.arrowProdEquivProdArrow α (fun a ↦ β) fun a ↦ γ)
        ⇑(Equiv.arrowProdEquivProdArrow α (fun a ↦ β) fun a ↦ γ))
      (𝓤 ((α →ᵤ β) × (α →ᵤ γ))) =
    𝓤 (α →ᵤ β × γ)

Tactic:
UniformFun

Goal state after:
α : Type u_1
β : Type u_2
γ : Type u_3
ι : Type u_4
p : Filter ι
inst✝¹ : UniformSpace β
inst✝ : UniformSpace γ
⊢ comap
      (Prod.map ⇑(Equiv.arrowProdEquivProdArrow α (fun a ↦ β) fun a ↦ γ)
        ⇑(Equiv.arrowProdEquivProdArrow α (fun a ↦ β) fun a ↦ γ))
      (𝓤 ((α → β) × (α → γ))) =
    𝓤 (α → β × γ)
Module: Mathlib.Topology.UniformSpace.Equicontinuity

Goal state before:
pp: ι : Type u_1
α : Type u_6
β : Type u_8
uα : UniformSpace α
uβ : UniformSpace β
F : ι → β → α
⊢ UniformEquicontinuous F ↔ UniformContinuous (⇑ofFun ∘ swap F)

Tactic:
rw [UniformContinuous, (UniformFun.hasBasis_uniformity ι α).tendsto_right_iff]

Goal state after:
ι : Type u_1
α : Type u_6
β : Type u_8
uα : UniformSpace α
uβ : UniformSpace β
F : ι → β → α
⊢ UniformEquicontinuous F ↔
    ∀ i ∈ 𝓤 α, ∀ᶠ (x : β × β) in 𝓤 β, ((⇑ofFun ∘ swap F) x.1, (⇑ofFun ∘ swap F) x.2) ∈ UniformFun.gen ι α i
Module: Mathlib.Topology.UniformSpace.UniformConvergenceTopology

Goal state before:
pp: case inr
α : Type u_1
β : Type u_2
γ : Type u_3
ι : Type u_4
s : Set α
p : Filter ι
inst✝¹ : UniformSpace β
𝔖 : Set (Set α)
inst✝ : CompleteSpace β
h✝ : Nonempty β
F : Filter (α →ᵤ[𝔖] β)
hF : Cauchy F
⊢ ∃ x, F ≤ 𝓝 x

Tactic:
have := hF.1

Goal state after:
case inr
α : Type u_1
β : Type u_2
γ : Type u_3
ι : Type u_4
s : Set α
p : Filter ι
inst✝¹ : UniformSpace β
𝔖 : Set (Set α)
inst✝ : CompleteSpace β
h✝ : Nonempty β
F : Filter (α →ᵤ[𝔖] β)
hF : Cauchy F
this : F.NeBot
⊢ ∃ x, F ≤ 𝓝 x
Module: Mathlib.Order.Filter.Pointwise

Goal state before:
pp: F : Type u_1
α : Type u_2
β : Type u_3
γ : Type u_4
δ : Type u_5
ε : Type u_6
inst✝³ : SMul α β
inst✝² : SMul α γ
inst✝¹ : SMul β γ
inst✝ : IsScalarTower α β γ
a : α
b : β
f : Filter γ
⊢ (a • b) • f = a • b • f

Tactic:
simp only [← Filter.map_smul, map_map, smul_assoc]; rfl

Goal state after:
Module: Mathlib.Topology.Algebra.MulAction

Goal state before:
pp: M : Type u_1
X : Type u_2
inst✝⁵ : TopologicalSpace M
inst✝⁴ : TopologicalSpace X
inst✝³ : Group M
inst✝² : IsTopologicalGroup M
inst✝¹ : MulAction M X
inst✝ : DiscreteTopology X
h : ∀ (x : X), IsOpen[inst✝⁵] ↑(MulAction.stabilizer M x)
y x : X
U : Set M := {m' | m' • y = x}
⊢ IsOpen[inst✝⁵] U

Tactic:
by_cases hU' : U ≠ ∅

Goal state after:
case pos
M : Type u_1
X : Type u_2
inst✝⁵ : TopologicalSpace M
inst✝⁴ : TopologicalSpace X
inst✝³ : Group M
inst✝² : IsTopologicalGroup M
inst✝¹ : MulAction M X
inst✝ : DiscreteTopology X
h : ∀ (x : X), IsOpen[inst✝⁵] ↑(MulAction.stabilizer M x)
y x : X
U : Set M := {m' | m' • y = x}
hU' : U ≠ ∅
⊢ IsOpen[inst✝⁵] U

case neg
M : Type u_1
X : Type u_2
inst✝⁵ : TopologicalSpace M
inst✝⁴ : TopologicalSpace X
inst✝³ : Group M
inst✝² : IsTopologicalGroup M
inst✝¹ : MulAction M X
inst✝ : DiscreteTopology X
h : ∀ (x : X), IsOpen[inst✝⁵] ↑(MulAction.stabilizer M x)
y x : X
U : Set M := {m' | m' • y = x}
hU' : ¬U ≠ ∅
⊢ IsOpen[inst✝⁵] U
Module: Mathlib.Algebra.Order.Group.Pointwise.Interval

Goal state before:
pp: α : Type u_1
inst✝² : Field α
inst✝¹ : LinearOrder α
inst✝ : IsStrictOrderedRing α
a : α
ha : a ≠ 0
b c : α
h : a < 0
⊢ (fun x ↦ x * a) ⁻¹' [[b, c]] = [[b / a, c / a]]

Tactic:
by
      simp [← Icc_min_max, h, h.le, min_div_div_right_of_nonpos, max_div_div_right_of_nonpos]

Goal state after:
Module: Mathlib.Topology.Algebra.ConstMulAction

Goal state before:
pp: case inl
G₀ : Type u_4
inst✝⁵ : GroupWithZero G₀
E : Type u_5
inst✝⁴ : Zero E
inst✝³ : MulActionWithZero G₀ E
inst✝² : TopologicalSpace E
inst✝¹ : T1Space E
inst✝ : ContinuousConstSMul G₀ E
⊢ IsClosedMap fun x ↦ 0 • x

Tactic:
simp only [zero_smul]
    exact isClosedMap_const

Goal state after:
Module: Mathlib.Topology.Algebra.Group.Basic

Goal state before:
pp: G : Type u_1
inst✝³ : DivInvMonoid G
inst✝² : TopologicalSpace G
inst✝¹ : ContinuousMul G
inst✝ : ContinuousInv G
x y : G
h : x ⤳ y
n : ℕ
⊢ (x ^ Int.negSucc n) ⤳ (y ^ Int.negSucc n)

Tactic:
by simpa using (h.pow (n + 1)).inv

Goal state after:
Module: Mathlib.Topology.Algebra.IsUniformGroup.Defs

Goal state before:
pp: β : Type u_2
inst✝³ : UniformSpace β
inst✝² : Group β
inst✝¹ : IsLeftUniformGroup β
inst✝ : IsRightUniformGroup β
⊢ Tendsto (fun gx ↦ gx.1 * gx.2 * gx.1⁻¹) (comap snd (𝓝 1)) (𝓝 1)

Tactic:
by
  rw [tendsto_iff_comap, comap_conj_nhds_one]

Goal state after:
Module: Mathlib.Topology.Algebra.IsUniformGroup.Defs

Goal state before:
pp: β : Type u_2
inst✝³ : UniformSpace β
inst✝² : Group β
inst✝¹ : IsLeftUniformGroup β
inst✝ : IsRightUniformGroup β
φ : (β × β) × β × β → β :=
  fun x ↦
    match x with
    | ((x₁, x₂), y₁, y₂) => x₂ * y₂⁻¹ * y₁ * x₁⁻¹
ψ : (β × β) × β × β → β :=
  fun x ↦
    match x with
    | ((x₁, x₂), y₁, y₂) => x₁⁻¹ * x₂ * (y₂⁻¹ * y₁)
g : (β × β) × β × β → β :=
  fun x ↦
    match x with
    | ((x₁, x₂), y₁, y₂) => x₁
this : Tendsto φ (𝓤 β ×ˢ 𝓤 β) (𝓝 1)
⊢ UniformContinuous fun p ↦ p.1 / p.2

Tactic:
by
      rw [UniformContinuous, uniformity_eq_comap_mul_inv_nhds_one β, tendsto_comap_iff,
        uniformity_prod_eq_prod, tendsto_map'_iff]
      simpa [Function.comp_def, div_eq_mul_inv, ← mul_assoc]

Goal state after:
Module: Mathlib.Order.Filter.AtTopBot.Group

Goal state before:
pp: G : Type u_2
inst✝² : CommGroup G
inst✝¹ : LinearOrder G
inst✝ : IsOrderedMonoid G
a b x : G
hx : x ≤ a ∧ x ≤ b⁻¹ ∨ a⁻¹ ≤ x ∧ b ≤ x
⊢ x ∈ Iic (a, b).1 ∪ Ici (a, b).2

Tactic:
exact hx.imp And.left And.right

Goal state after:
Module: Mathlib.Topology.Algebra.IsUniformGroup.Basic

Goal state before:
pp: α : Type u_1
β : Type u_2
δ : Type u_4
G : Type u_5
inst✝⁸ : TopologicalSpace α
inst✝⁷ : AddCommGroup α
inst✝⁶ : IsTopologicalAddGroup α
inst✝⁵ : TopologicalSpace β
inst✝⁴ : AddCommGroup β
inst✝³ : TopologicalSpace δ
inst✝² : AddCommGroup δ
inst✝¹ : UniformSpace G
inst✝ : AddCommGroup G
e : β →+ α
de : IsDenseInducing ⇑e
φ : β →+ δ →+ G
hφ : Continuous[instTopologicalSpaceProd, inst✝¹.toTopologicalSpace] fun p ↦ (φ p.1) p.2
W' : Set G
W'_nhds : W' ∈ 𝓝 0
x₀ : α
y₁ : δ
Nx : Filter α := 𝓝 x₀
ee : β × β → α × α := fun u ↦ (e u.1, e u.2)
lim1 : Tendsto (fun a ↦ (a.2 - a.1, y₁)) (comap (⇑e) Nx ×ˢ comap (⇑e) Nx) (𝓝 (0, y₁))
lim2 : Tendsto (fun p ↦ (φ p.1) p.2) (𝓝 (0, y₁)) (𝓝 0)
lim : Tendsto ((fun p ↦ (φ p.1) p.2) ∘ fun a ↦ (a.2 - a.1, y₁)) (comap (⇑e) Nx ×ˢ comap (⇑e) Nx) (𝓝 0)
⊢ ∃ U₂ ∈ comap (⇑e) (𝓝 x₀), ∀ x ∈ U₂, ∀ x' ∈ U₂, (fun p ↦ (φ p.1) p.2) (x' - x, y₁) ∈ W'

Tactic:
tendsto_prod_self_iff

Goal state after:
α : Type u_1
β : Type u_2
δ : Type u_4
G : Type u_5
inst✝⁸ : TopologicalSpace α
inst✝⁷ : AddCommGroup α
inst✝⁶ : IsTopologicalAddGroup α
inst✝⁵ : TopologicalSpace β
inst✝⁴ : AddCommGroup β
inst✝³ : TopologicalSpace δ
inst✝² : AddCommGroup δ
inst✝¹ : UniformSpace G
inst✝ : AddCommGroup G
e : β →+ α
de : IsDenseInducing ⇑e
φ : β →+ δ →+ G
hφ : Continuous[instTopologicalSpaceProd, inst✝¹.toTopologicalSpace] fun p ↦ (φ p.1) p.2
W' : Set G
W'_nhds : W' ∈ 𝓝 0
x₀ : α
y₁ : δ
Nx : Filter α := 𝓝 x₀
ee : β × β → α × α := fun u ↦ (e u.1, e u.2)
lim1 : Tendsto (fun a ↦ (a.2 - a.1, y₁)) (comap (⇑e) Nx ×ˢ comap (⇑e) Nx) (𝓝 (0, y₁))
lim2 : Tendsto (fun p ↦ (φ p.1) p.2) (𝓝 (0, y₁)) (𝓝 0)
lim :
  ∀ W ∈ 𝓝 0,
    ∃ U ∈ comap (⇑e) Nx, ∀ (x x' : β), x ∈ U → x' ∈ U → ((fun p ↦ (φ p.1) p.2) ∘ fun a ↦ (a.2 - a.1, y₁)) (x, x') ∈ W
⊢ ∃ U₂ ∈ comap (⇑e) (𝓝 x₀), ∀ x ∈ U₂, ∀ x' ∈ U₂, (fun p ↦ (φ p.1) p.2) (x' - x, y₁) ∈ W'
Module: Mathlib.Order.Filter.Interval

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝ : PartialOrder α
a : α
⊢ TendstoIxxClass Icc (𝓟 {a}) (𝓟 {a})

Tactic:
exact tendstoIxxClass_principal.2 ordConnected_singleton.out

Goal state after:
Module: Mathlib.Topology.Algebra.IsUniformGroup.Basic

Goal state before:
pp: case left
α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
G : Type u_5
inst✝¹⁴ : TopologicalSpace α
inst✝¹³ : AddCommGroup α
inst✝¹² : IsTopologicalAddGroup α
inst✝¹¹ : TopologicalSpace β
inst✝¹⁰ : AddCommGroup β
inst✝⁹ : TopologicalSpace γ
inst✝⁸ : AddCommGroup γ
inst✝⁷ : IsTopologicalAddGroup γ
inst✝⁶ : TopologicalSpace δ
inst✝⁵ : AddCommGroup δ
inst✝⁴ : UniformSpace G
inst✝³ : AddCommGroup G
e : β →+ α
de : IsDenseInducing ⇑e
f : δ →+ γ
df : IsDenseInducing ⇑f
φ : β →+ δ →+ G
hφ : Continuous[instTopologicalSpaceProd, inst✝⁴.toTopologicalSpace] fun p ↦ (φ p.1) p.2
inst✝² : IsUniformAddGroup G
inst✝¹ : T0Space G
inst✝ : CompleteSpace G
x₀ : α
y₀ : γ
⊢ ∀ t ∈ 𝓝 (x₀, y₀), ∃ a, Prod.map (⇑e) (⇑f) a ∈ t

Tactic:
intro U h

Goal state after:
case left
α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
G : Type u_5
inst✝¹⁴ : TopologicalSpace α
inst✝¹³ : AddCommGroup α
inst✝¹² : IsTopologicalAddGroup α
inst✝¹¹ : TopologicalSpace β
inst✝¹⁰ : AddCommGroup β
inst✝⁹ : TopologicalSpace γ
inst✝⁸ : AddCommGroup γ
inst✝⁷ : IsTopologicalAddGroup γ
inst✝⁶ : TopologicalSpace δ
inst✝⁵ : AddCommGroup δ
inst✝⁴ : UniformSpace G
inst✝³ : AddCommGroup G
e : β →+ α
de : IsDenseInducing ⇑e
f : δ →+ γ
df : IsDenseInducing ⇑f
φ : β →+ δ →+ G
hφ : Continuous[instTopologicalSpaceProd, inst✝⁴.toTopologicalSpace] fun p ↦ (φ p.1) p.2
inst✝² : IsUniformAddGroup G
inst✝¹ : T0Space G
inst✝ : CompleteSpace G
x₀ : α
y₀ : γ
U : Set (α × γ)
h : U ∈ 𝓝 (x₀, y₀)
⊢ ∃ a, Prod.map (⇑e) (⇑f) a ∈ U
Module: Mathlib.Topology.Algebra.Order.Field

Goal state before:
pp: case refine_1
𝕜 : Type u_1
α : Type u_2
inst✝⁵ : Semifield 𝕜
inst✝⁴ : LinearOrder 𝕜
inst✝³ : IsStrictOrderedRing 𝕜
inst✝² : TopologicalSpace 𝕜
inst✝¹ : OrderTopology 𝕜
l : Filter α
f g : α → 𝕜
inst✝ : ContinuousMul 𝕜
x : 𝕜
hx : x < 1
⊢ ∀ᶠ (b : 𝕜) in 𝓝 1, x < b⁻¹

Tactic:
obtain ⟨x', h₀, hxx', h₁⟩ : ∃ x', 0 < x' ∧ x ≤ x' ∧ x' < 1 :=
      ⟨max x (1 / 2), one_half_pos.trans_le (le_max_right _ _), le_max_left _ _,
        max_lt hx one_half_lt_one⟩
    filter_upwards [Ioo_mem_nhds one_pos ((one_lt_inv₀ h₀).2 h₁)] with y hy
    exact hxx'.trans_lt <| lt_inv_of_lt_inv₀ hy.1 hy.2

Goal state after:
Module: Mathlib.Algebra.Category.Grp.Images

Goal state before:
pp: G H : AddCommGrpCat
f : G ⟶ H
F' : MonoFactorisation f
⊢ lift F' ≫ F'.m = ι f

Tactic:
ext x
  change (F'.e ≫ F'.m) _ = _
  rw [F'.fac, (Classical.indefiniteDescription _ x.2).2]
  rfl

Goal state after:
Module: Mathlib.CategoryTheory.ObjectProperty.EpiMono

Goal state before:
pp: C : Type u
inst✝² : Category.{v, u} C
P : ObjectProperty C
inst✝¹ : P.IsClosedUnderSubobjects
inst✝ : HasZeroMorphisms C
S : ShortComplex C
hS : S.ShortExact
h₂ : P S.X₂
⊢ P S.X₁

Tactic:
by
  have := hS.mono_f
  exact P.prop_of_mono S.f h₂

Goal state after:
Module: Mathlib.Algebra.Module.CharacterModule

Goal state before:
pp: R : Type uR
inst✝⁴ : CommRing R
A : Type uA
inst✝³ : AddCommGroup A
A' : Type u_1
inst✝² : AddCommGroup A'
inst✝¹ : Module R A
inst✝ : Module R A'
f : A →ₗ[R] A'
hf : Function.Injective ⇑(dual f)
⊢ Function.Surjective ⇑f

Tactic:
rw [← LinearMap.range_eq_top, ← Submodule.unique_quotient_iff_eq_top]
  refine ⟨Unique.mk inferInstance fun a ↦ eq_zero_of_character_apply fun c ↦ ?_⟩
  obtain ⟨b, rfl⟩ := QuotientAddGroup.mk'_surjective _ a
  suffices eq : dual (Submodule.mkQ _) c = 0 from congr($eq b)
  refine hf ?_
  rw [← LinearMap.comp_apply, ← dual_comp, LinearMap.range_mkQ_comp, dual_zero,
    LinearMap.zero_apply, dual_apply, AddMonoidHom.zero_comp]

Goal state after: