mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Combinatorics.Matroid.Dual

Goal state before:
pp: case refine_2
α : Type u_1
M : Matroid α
B X : Set α
hB : M.IsBase B
hBX : M.IsBasis (B ∩ X) X
e : α
he : (e ∈ M.E ∧ e ∉ X) ∧ e ∈ B
B' : Set α
hB' : M.IsBase B'
hem : B' ∩ (B ∪ X)ᶜ = ∅ ∧ e ∉ B'
⊢ False

Tactic:
← sdiff_eq,

Goal state after:
case refine_2
α : Type u_1
M : Matroid α
B X : Set α
hB : M.IsBase B
hBX : M.IsBasis (B ∩ X) X
e : α
he : (e ∈ M.E ∧ e ∉ X) ∧ e ∈ B
B' : Set α
hB' : M.IsBase B'
hem : B' \ (B ∪ X) = ∅ ∧ e ∉ B'
⊢ False
Module: Mathlib.Combinatorics.Matroid.Minor.Restrict

Goal state before:
pp: α : Type u_1
M N : Matroid α
h : N <r M
⊢ N = M ↾ N.E

Tactic:
h.eq_restrict

Goal state after:
α : Type u_1
M N : Matroid α
h : N <r M
⊢ N = N
Module: Mathlib.Combinatorics.Matroid.Rank.Finite

Goal state before:
pp: α : Type u_1
M : Matroid α
e : α
⊢ M.IsRkFinite {e}

Tactic:
by
  simp

Goal state after:
Module: Mathlib.Combinatorics.Matroid.Rank.Finite

Goal state before:
pp: α : Type u_1
M : Matroid α
⊢ M.IsRkFinite M.E ↔ M.RankFinite

Tactic:
rw [IsRkFinite, restrict_ground_eq_self]

Goal state after:
Module: Mathlib.Combinatorics.Matroid.Rank.Finite

Goal state before:
pp: α : Type u_1
M : Matroid α
X : Set α
h : M.IsRkFinite (X ∩ M.E)
⊢ M.IsRkFinite (M.closure X)

Tactic:
simpa using h.closure

Goal state after:
Module: Mathlib.Combinatorics.Matroid.Map

Goal state before:
pp: α : Type u_1
β : Type u_2
M : Matroid α
B : Set α
hB : M.IsBase B
f : α → β
hf : InjOn f M.E
⊢ (M.map f hf).IsBase (f '' B)

Tactic:
rw [map_isBase_iff]; exact ⟨B, hB, rfl⟩

Goal state after:
Module: Mathlib.Combinatorics.Matroid.Map

Goal state before:
pp: α : Type u_1
β : Type u_2
M : Matroid α
f : α ↪ β
I : Set β
x✝ : M.Indep (⇑f ⁻¹' I) ∧ I ⊆ range ⇑f
h : M.Indep (⇑f ⁻¹' I)
h' : I ⊆ range ⇑f
⊢ ⇑f '' ⇑f ⁻¹' I = I

Tactic:
image_preimage_eq_iff

Goal state after:
α : Type u_1
β : Type u_2
M : Matroid α
f : α ↪ β
I : Set β
x✝ : M.Indep (⇑f ⁻¹' I) ∧ I ⊆ range ⇑f
h : M.Indep (⇑f ⁻¹' I)
h' : I ⊆ range ⇑f
⊢ I ⊆ range ⇑f
Module: Mathlib.Combinatorics.Matroid.Map

Goal state before:
pp: α : Type u_1
β : Type u_2
M : Matroid α
f : α ↪ β
B : Set β
x✝ : M.IsBase (⇑f ⁻¹' B) ∧ B ⊆ range ⇑f
h : M.IsBase (⇑f ⁻¹' B)
h' : B ⊆ range ⇑f
⊢ ⇑f '' ⇑f ⁻¹' B = B

Tactic:
image_preimage_eq_iff

Goal state after:
α : Type u_1
β : Type u_2
M : Matroid α
f : α ↪ β
B : Set β
x✝ : M.IsBase (⇑f ⁻¹' B) ∧ B ⊆ range ⇑f
h : M.IsBase (⇑f ⁻¹' B)
h' : B ⊆ range ⇑f
⊢ B ⊆ range ⇑f
Module: Mathlib.Combinatorics.Matroid.Map

Goal state before:
pp: case refine_1
α : Type u_1
β : Type u_2
M : Matroid α
f : α ↪ β
I X : Set α
hIX : M.IsBasis I X
⊢ M.IsBasis (⇑f ⁻¹' ⇑f '' I) (⇑f ⁻¹' ⇑f '' X) ∧ ⇑f '' I ⊆ ⇑f '' X ∧ ⇑f '' X ⊆ range ⇑f

Tactic:
simp [preimage_image_eq _ f.injective, image_mono hIX.subset, hIX]

Goal state after:
Module: Mathlib.Combinatorics.Matroid.Map

Goal state before:
pp: α : Type u_1
M : Matroid α
⊢ (M.restrictSubtype M.E).map Subtype.val ⋯ = M

Tactic:
by
  simp

Goal state after:
Module: Mathlib.Combinatorics.Matroid.Map

Goal state before:
pp: α : Type u_1
β : Type u_2
f : α → β
E✝ I✝ : Set α
M✝ : Matroid α
N : Matroid β
E X I : Set α
M : Matroid α
inst✝ : M.RankPos
⊢ (M.restrictSubtype M.E).RankPos

Tactic:
obtain ⟨B, hB⟩ := (M.restrictSubtype M.E).exists_isBase

Goal state after:
α : Type u_1
β : Type u_2
f : α → β
E✝ I✝ : Set α
M✝ : Matroid α
N : Matroid β
E X I : Set α
M : Matroid α
inst✝ : M.RankPos
B : Set ↑M.E
hB : (M.restrictSubtype M.E).IsBase B
⊢ (M.restrictSubtype M.E).RankPos
Module: Mathlib.Combinatorics.Matroid.Rank.ENat

Goal state before:
pp: α : Type u_1
M : Matroid α
X Y Ii : Set α
hIi : M.IsBasis' Ii (X ∩ Y)
⊢ M.eRk (X ∩ Y) + M.eRk (X ∪ Y) ≤ M.eRk X + M.eRk Y

Tactic:
obtain ⟨IX, hIX, hIX'⟩ :=
    hIi.indep.subset_isBasis'_of_subset (hIi.subset.trans inter_subset_left)

Goal state after:
α : Type u_1
M : Matroid α
X Y Ii : Set α
hIi : M.IsBasis' Ii (X ∩ Y)
IX : Set α
hIX : M.IsBasis' IX X
hIX' : Ii ⊆ IX
⊢ M.eRk (X ∩ Y) + M.eRk (X ∪ Y) ≤ M.eRk X + M.eRk Y
Module: Mathlib.Combinatorics.Matroid.Loop

Goal state before:
pp: α : Type u_1
M : Matroid α
e : α
⊢ M.IsCocircuit {e} ↔ M.IsColoop e

Tactic:
by
  simp

Goal state after:
Module: Mathlib.Combinatorics.Matroid.Rank.ENat

Goal state before:
pp: α : Type u_1
M : Matroid α
X : Set α
⊢ M.eRk X ≠ ⊤ ↔ M.IsRkFinite X

Tactic:
by
  simp

Goal state after:
Module: Mathlib.Combinatorics.Matroid.Rank.ENat

Goal state before:
pp: α : Type u_1
M : Matroid α
X : Set α
hX : M.Spanning X
⊢ (M ↾ X).eRank = M.eRank

Tactic:
by
  rw [eRank_def, restrict_ground_eq, restrict_eRk_eq _ rfl.subset, hX.eRk_eq]

Goal state after:
Module: Mathlib.Combinatorics.Matroid.Circuit

Goal state before:
pp: α : Type u_1
M : Matroid α
⊢ M.Finitary ↔ ∀ (C : Set α), M.IsCircuit C → C.Finite

Tactic:
by
  refine ⟨fun _ _ ↦ IsCircuit.finite, fun h ↦
    ⟨fun I hI ↦ indep_iff_not_dep.2 ⟨fun hd ↦ ?_,fun x hx ↦ ?_⟩⟩⟩
  · obtain ⟨C, hCI, hC⟩ := hd.exists_isCircuit_subset
    exact hC.dep.not_indep <| hI _ hCI (h C hC)
  simpa using (hI {x} (by simpa) (finite_singleton _)).subset_ground

Goal state after:
Module: Mathlib.Combinatorics.Matroid.Circuit

Goal state before:
pp: α : Type u_1
M : Matroid α
X : Set α
e : α
inst✝ : M.Finitary
he : e ∈ M.closure X
⊢ ∃ I ⊆ X, I.Finite ∧ M.Indep I ∧ e ∈ M.closure I

Tactic:
by_cases heY : e ∈ X

Goal state after:
case pos
α : Type u_1
M : Matroid α
X : Set α
e : α
inst✝ : M.Finitary
he : e ∈ M.closure X
heY : e ∈ X
⊢ ∃ I ⊆ X, I.Finite ∧ M.Indep I ∧ e ∈ M.closure I

case neg
α : Type u_1
M : Matroid α
X : Set α
e : α
inst✝ : M.Finitary
he : e ∈ M.closure X
heY : e ∉ X
⊢ ∃ I ⊆ X, I.Finite ∧ M.Indep I ∧ e ∈ M.closure I
Module: Mathlib.Combinatorics.Matroid.Loop

Goal state before:
pp: α : Type u_1
M : Matroid α
⊢ M.removeLoops.removeLoops = M.removeLoops

Tactic:
by
  simp

Goal state after:
Module: Mathlib.Combinatorics.Matroid.Rank.Cardinal

Goal state before:
pp: α : Type u
M : Matroid α
inst✝ : M.InvariantCardinalRank
X I : Set α
hI : M.IsBasis' I X
⊢ #↑I = M.cRk X

Tactic:
← hI.cardinalMk_eq_cRk

Goal state after:
α : Type u
M : Matroid α
inst✝ : M.InvariantCardinalRank
X I : Set α
hI : M.IsBasis' I X
⊢ #↑I = #↑I
Module: Mathlib.Combinatorics.Matroid.Rank.Cardinal

Goal state before:
pp: α : Type u
M : Matroid α
inst✝ : M.InvariantCardinalRank
X Y : Set α
⊢ M.cRk (M.closure X ∪ M.closure Y) = M.cRk (X ∪ Y)

Tactic:
by
  simp

Goal state after:
Module: Mathlib.Combinatorics.Matroid.Rank.Cardinal

Goal state before:
pp: α : Type u
M : Matroid α
inst✝ : M.InvariantCardinalRank
X Y Ii : Set α
hIi : M.IsBasis' Ii (X ∩ Y)
⊢ M.cRk (X ∩ Y) + M.cRk (X ∪ Y) ≤ M.cRk X + M.cRk Y

Tactic:
obtain ⟨IX, hIX, hIX'⟩ :=
    hIi.indep.subset_isBasis'_of_subset (hIi.subset.trans inter_subset_left)

Goal state after:
α : Type u
M : Matroid α
inst✝ : M.InvariantCardinalRank
X Y Ii : Set α
hIi : M.IsBasis' Ii (X ∩ Y)
IX : Set α
hIX : M.IsBasis' IX X
hIX' : Ii ⊆ IX
⊢ M.cRk (X ∩ Y) + M.cRk (X ∪ Y) ≤ M.cRk X + M.cRk Y
Module: Mathlib.RingTheory.AlgebraicIndependent.Transcendental

Goal state before:
pp: R : Type u_3
A : Type v
inst✝² : CommRing R
inst✝¹ : CommRing A
inst✝ : Algebra R A
x : A
⊢ AlgebraicIndependent R ![x] ↔ Transcendental R x

Tactic:
by
  simp

Goal state after:
Module: Mathlib.Combinatorics.Matroid.Closure

Goal state before:
pp: α : Type u_2
M : Matroid α
X : Set α
e f : α
he : e ∉ M.closure (X ∩ M.E)
hef : e ∈ M.closure (insert f X ∩ M.E)
hfE : f ∉ M.E
⊢ False

Tactic:
rw [insert_inter_of_notMem hfE] at hef

Goal state after:
α : Type u_2
M : Matroid α
X : Set α
e f : α
he : e ∉ M.closure (X ∩ M.E)
hef : e ∈ M.closure (X ∩ M.E)
hfE : f ∉ M.E
⊢ False
Module: Mathlib.Combinatorics.Matroid.Closure

Goal state before:
pp: α : Type u_2
M : Matroid α
I : Set α
hI : M.Indep I
hIs : M.Spanning I
B : Set α
hB : M.IsBase B
hBI : B ⊆ I
⊢ M.IsBase I

Tactic:
← hB.eq_of_subset_indep hI hBI

Goal state after:
α : Type u_2
M : Matroid α
I : Set α
hI : M.Indep I
hIs : M.Spanning I
B : Set α
hB : M.IsBase B
hBI : B ⊆ I
⊢ M.IsBase B
Module: Mathlib.RingTheory.Polynomial.SeparableDegree

Goal state before:
pp: case inl
F✝ : Type u_1
inst✝² : Field F✝
q✝ : ℕ
F : Type u_1
inst✝¹ : Field F
q : ℕ
hq : NeZero q
inst✝ : CharP F q
g' : F[X]
m : ℕ
hg' : g'.Separable
s : ℕ
hm : m ≤ m + s
hg : ((expand F (q ^ s)) g').Separable
h : IsUnit g'
⊢ ((expand F (q ^ s)) g').natDegree = g'.natDegree

Tactic:
natDegree_expand,

Goal state after:
case inl
F✝ : Type u_1
inst✝² : Field F✝
q✝ : ℕ
F : Type u_1
inst✝¹ : Field F
q : ℕ
hq : NeZero q
inst✝ : CharP F q
g' : F[X]
m : ℕ
hg' : g'.Separable
s : ℕ
hm : m ≤ m + s
hg : ((expand F (q ^ s)) g').Separable
h : IsUnit g'
⊢ g'.natDegree * q ^ s = g'.natDegree
Module: Mathlib.RingTheory.Polynomial.SeparableDegree

Goal state before:
pp: case inr
F✝ : Type u_1
inst✝² : Field F✝
q✝ : ℕ
F : Type u_1
inst✝¹ : Field F
q : ℕ
hq : NeZero q
inst✝ : CharP F q
g' : F[X]
m : ℕ
hg' : g'.Separable
hm : m ≤ m + 0
hg : ((expand F (q ^ 0)) g').Separable
⊢ ((expand F (q ^ 0)) g').natDegree = g'.natDegree

Tactic:
natDegree_expand,

Goal state after:
case inr
F✝ : Type u_1
inst✝² : Field F✝
q✝ : ℕ
F : Type u_1
inst✝¹ : Field F
q : ℕ
hq : NeZero q
inst✝ : CharP F q
g' : F[X]
m : ℕ
hg' : g'.Separable
hm : m ≤ m + 0
hg : ((expand F (q ^ 0)) g').Separable
⊢ g'.natDegree * q ^ 0 = g'.natDegree
Module: Mathlib.RingTheory.AlgebraicIndependent.Basic

Goal state before:
pp: ι : Type u
R : Type u_2
A : Type v
x : ι → A
inst✝² : CommRing R
inst✝¹ : CommRing A
inst✝ : Algebra R A
hx : AlgebraicIndependent R x
r : R
⊢ hx.mvPolynomialOptionEquivPolynomialAdjoin (C r) = Polynomial.C ((algebraMap R ↥(adjoin R (range x))) r)

Tactic:
by
  simp

Goal state after:
Module: Mathlib.GroupTheory.GroupAction.FixedPoints

Goal state before:
pp: G : Type u_1
A : Type u_2
B : Type u_3
inst✝² : Monoid G
inst✝¹ : MulAction G A
inst✝ : MulAction G B
f : A →ₑ[id] B
H : Submonoid G
a : A
ha : a ∈ MulAction.fixedPoints (↥H) A
⊢ f a ∈ MulAction.fixedPoints (↥H) B

Tactic:
intro ⟨h, _⟩
  simp_all [← f.map_smul h a]

Goal state after:
Module: Mathlib.RingTheory.AlgebraicIndependent.TranscendenceBasis

Goal state before:
pp: R : Type u_1
A : Type w
inst✝⁴ : CommRing R
inst✝³ : CommRing A
inst✝² : Algebra R A
inst✝¹ : FaithfulSMul R A
inst✝ : IsDomain A
s : Set A
⊢ (matroid R A).closure s = ↑(algebraicClosure (↥(adjoin R s)) A)

Tactic:
have ⟨B, hB⟩ := (matroid R A).exists_isBasis s

Goal state after:
R : Type u_1
A : Type w
inst✝⁴ : CommRing R
inst✝³ : CommRing A
inst✝² : Algebra R A
inst✝¹ : FaithfulSMul R A
inst✝ : IsDomain A
s B : Set A
hB : (matroid R A).IsBasis B s
⊢ (matroid R A).closure s = ↑(algebraicClosure (↥(adjoin R s)) A)
Module: Mathlib.RingTheory.AlgebraicIndependent.TranscendenceBasis

Goal state before:
pp: R : Type u_1
A : Type w
inst✝³ : CommRing R
inst✝² : CommRing A
inst✝¹ : Algebra R A
inst✝ : NoZeroDivisors A
s t : Set A
hst : s ⊆ t
hs : AlgebraicIndepOn R _root_.id s
ht : Algebra.IsAlgebraic (↥(adjoin R t)) A
this✝² : Nontrivial ↥(adjoin R t)
this✝¹ : Nontrivial A
this✝ : IsDomain A
this : FaithfulSMul R A
⊢ ∃ u, s ⊆ u ∧ u ⊆ t ∧ IsTranscendenceBasis R Subtype.val

Tactic:
rw [← matroid_spanning_iff] at ht

Goal state after:
R : Type u_1
A : Type w
inst✝³ : CommRing R
inst✝² : CommRing A
inst✝¹ : Algebra R A
inst✝ : NoZeroDivisors A
s t : Set A
hst : s ⊆ t
hs : AlgebraicIndepOn R _root_.id s
this✝² : Nontrivial ↥(adjoin R t)
this✝¹ : Nontrivial A
this✝ : IsDomain A
this : FaithfulSMul R A
ht : (matroid R A).Spanning t
⊢ ∃ u, s ⊆ u ∧ u ⊆ t ∧ IsTranscendenceBasis R Subtype.val
Module: Mathlib.RingTheory.AlgebraicIndependent.TranscendenceBasis

Goal state before:
pp: ι : Type u
R : Type u_1
S : Type v
inst✝⁴ : CommRing R
inst✝³ : CommRing S
inst✝² : Algebra R S
inst✝¹ : FaithfulSMul R S
inst✝ : NoZeroDivisors S
s : Set ι
i j : ι
v : ι → S
hj✝ : j ∈ insert i s
H₁ : IsTranscendenceBasis R fun x ↦ v ↑x
this✝³ : Nontrivial ↥(adjoin R (v '' (insert i s \ {j})))
this✝² : Nontrivial S
this✝¹ : IsDomain S
H₂ : v j ∈ (matroid R S).closure (v '' (insert i s \ {j}))
this✝ : Nontrivial R
inj : InjOn v s
H' : (matroid R S).IsBase (v '' s)
hj : j ∈ s
Hj : v j ∉ (matroid R S).closure (v '' s \ {v j})
hi : i ∉ s
ne : v i ≠ v j
hi' : v i ∉ v '' s
this : InjOn v (insert i s)
⊢ Injective fun x ↦ v ↑x

Tactic:
by exact injOn_iff_injective.1 (this.mono sdiff_subset)

Goal state after:
Module: Mathlib.FieldTheory.SeparableDegree

Goal state before:
pp: F : Type u
inst✝ : Field F
f : F[X]
hm : f.Monic
hs : f.Splits
h : f.natSepDegree = 1
h1 : f = (Multiset.map (fun x ↦ X - C x) f.roots).prod
h2 : f.roots.card ≠ 0
y : F
h3 : f.roots = f.roots.card • {y}
⊢ f = (X - C y) ^ f.roots.card

Tactic:
h3,

Goal state after:
F : Type u
inst✝ : Field F
f : F[X]
hm : f.Monic
hs : f.Splits
h : f.natSepDegree = 1
h2 : f.roots.card ≠ 0
y : F
h1 : f = (Multiset.map (fun x ↦ X - C x) (f.roots.card • {y})).prod
h3 : f.roots = f.roots.card • {y}
⊢ f = (X - C y) ^ f.roots.card
Module: Mathlib.Topology.Algebra.FilterBasis

Goal state before:
pp: case refine_3
G : Type u
inst✝ : Group G
B✝ B : GroupFilterBasis G
this : TopologicalSpace G := B.topology
basis : (𝓝 1).HasBasis (fun V ↦ V ∈ B) id
basis' : (𝓝 1 ×ˢ 𝓝 1).HasBasis (fun i ↦ i.1 ∈ B ∧ i.2 ∈ B) fun i ↦ id i.1 ×ˢ id i.2
⊢ ∀ (x₀ : G), 𝓝 x₀ = map (fun x ↦ x₀ * x) (𝓝 1)

Tactic:
intro x₀

Goal state after:
case refine_3
G : Type u
inst✝ : Group G
B✝ B : GroupFilterBasis G
this : TopologicalSpace G := B.topology
basis : (𝓝 1).HasBasis (fun V ↦ V ∈ B) id
basis' : (𝓝 1 ×ˢ 𝓝 1).HasBasis (fun i ↦ i.1 ∈ B ∧ i.2 ∈ B) fun i ↦ id i.1 ×ˢ id i.2
x₀ : G
⊢ 𝓝 x₀ = map (fun x ↦ x₀ * x) (𝓝 1)
Module: Mathlib.Topology.Algebra.FilterBasis

Goal state before:
pp: case refine_4
G : Type u
inst✝ : Group G
B✝ B : GroupFilterBasis G
this : TopologicalSpace G := B.topology
basis : (𝓝 1).HasBasis (fun V ↦ V ∈ B) id
basis' : (𝓝 1 ×ˢ 𝓝 1).HasBasis (fun i ↦ i.1 ∈ B ∧ i.2 ∈ B) fun i ↦ id i.1 ×ˢ id i.2
⊢ ∀ (x₀ : G), Tendsto (fun x ↦ x₀ * x * x₀⁻¹) (𝓝 1) (𝓝 1)

Tactic:
intro x₀

Goal state after:
case refine_4
G : Type u
inst✝ : Group G
B✝ B : GroupFilterBasis G
this : TopologicalSpace G := B.topology
basis : (𝓝 1).HasBasis (fun V ↦ V ∈ B) id
basis' : (𝓝 1 ×ˢ 𝓝 1).HasBasis (fun i ↦ i.1 ∈ B ∧ i.2 ∈ B) fun i ↦ id i.1 ×ˢ id i.2
x₀ : G
⊢ Tendsto (fun x ↦ x₀ * x * x₀⁻¹) (𝓝 1) (𝓝 1)
Module: Mathlib.FieldTheory.Galois.Basic

Goal state before:
pp: F : Type u_1
inst✝⁴ : Field F
E : Type u_2
inst✝³ : Field E
inst✝² : Algebra F E
inst✝¹ : FiniteDimensional F E
inst✝ : IsGalois F E
α : E
hα : F⟮α⟯ = ⊤
iso : ↥F⟮α⟯ ≃ₐ[F] E :=
  { toFun := fun e ↦ ↑e, invFun := fun e ↦ ⟨e, ⋯⟩, left_inv := ⋯, right_inv := ⋯, map_mul' := ⋯, map_add' := ⋯,
    commutes' := ⋯ }
H : IsIntegral F α
h_sep : IsSeparable F α
h_splits : (Polynomial.map (algebraMap F ↥F⟮α⟯) (minpoly F α)).Splits
⊢ Nat.card Gal(E/F) = finrank F ↥F⟮α⟯

Tactic:
← IntermediateField.AdjoinSimple.card_aut_eq_finrank F E H h_sep h_splits

Goal state after:
F : Type u_1
inst✝⁴ : Field F
E : Type u_2
inst✝³ : Field E
inst✝² : Algebra F E
inst✝¹ : FiniteDimensional F E
inst✝ : IsGalois F E
α : E
hα : F⟮α⟯ = ⊤
iso : ↥F⟮α⟯ ≃ₐ[F] E :=
  { toFun := fun e ↦ ↑e, invFun := fun e ↦ ⟨e, ⋯⟩, left_inv := ⋯, right_inv := ⋯, map_mul' := ⋯, map_add' := ⋯,
    commutes' := ⋯ }
H : IsIntegral F α
h_sep : IsSeparable F α
h_splits : (Polynomial.map (algebraMap F ↥F⟮α⟯) (minpoly F α)).Splits
⊢ Nat.card Gal(E/F) = Nat.card Gal(↥F⟮α⟯/F)
Module: Mathlib.Topology.Algebra.FilterBasis

Goal state before:
pp: case hmul_left
R✝ : Type u
inst✝¹ : Ring R✝
B✝ : RingFilterBasis R✝
R : Type u
inst✝ : Ring R
B : RingFilterBasis R
B' : AddGroupFilterBasis R := ⋯
this✝ : TopologicalSpace R := ⋯
basis : (𝓝 0).HasBasis (fun V ↦ V ∈ B') id
basis' : (𝓝 0 ×ˢ 𝓝 0).HasBasis (fun i ↦ i.1 ∈ B' ∧ i.2 ∈ B') fun i ↦ id i.1 ×ˢ id i.2
this : IsTopologicalAddGroup R
⊢ ∀ (x₀ : R), Tendsto (fun x ↦ x₀ * x) (𝓝 0) (𝓝 0)

Tactic:
intro x₀

Goal state after:
case hmul_left
R✝ : Type u
inst✝¹ : Ring R✝
B✝ : RingFilterBasis R✝
R : Type u
inst✝ : Ring R
B : RingFilterBasis R
B' : AddGroupFilterBasis R := B.toAddGroupFilterBasis
this✝ : TopologicalSpace R := B'.topology
basis : (𝓝 0).HasBasis (fun V ↦ V ∈ B') id
basis' : (𝓝 0 ×ˢ 𝓝 0).HasBasis (fun i ↦ i.1 ∈ B' ∧ i.2 ∈ B') fun i ↦ id i.1 ×ˢ id i.2
this : IsTopologicalAddGroup R
x₀ : R
⊢ Tendsto (fun x ↦ x₀ * x) (𝓝 0) (𝓝 0)
Module: Mathlib.Topology.Algebra.FilterBasis

Goal state before:
pp: case hmul_right
R✝ : Type u
inst✝¹ : Ring R✝
B✝ : RingFilterBasis R✝
R : Type u
inst✝ : Ring R
B : RingFilterBasis R
B' : AddGroupFilterBasis R := ⋯
this✝ : TopologicalSpace R := ⋯
basis : (𝓝 0).HasBasis (fun V ↦ V ∈ B') id
basis' : (𝓝 0 ×ˢ 𝓝 0).HasBasis (fun i ↦ i.1 ∈ B' ∧ i.2 ∈ B') fun i ↦ id i.1 ×ˢ id i.2
this : IsTopologicalAddGroup R
⊢ ∀ (x₀ : R), Tendsto (fun x ↦ x * x₀) (𝓝 0) (𝓝 0)

Tactic:
intro x₀

Goal state after:
case hmul_right
R✝ : Type u
inst✝¹ : Ring R✝
B✝ : RingFilterBasis R✝
R : Type u
inst✝ : Ring R
B : RingFilterBasis R
B' : AddGroupFilterBasis R := B.toAddGroupFilterBasis
this✝ : TopologicalSpace R := B'.topology
basis : (𝓝 0).HasBasis (fun V ↦ V ∈ B') id
basis' : (𝓝 0 ×ˢ 𝓝 0).HasBasis (fun i ↦ i.1 ∈ B' ∧ i.2 ∈ B') fun i ↦ id i.1 ×ˢ id i.2
this : IsTopologicalAddGroup R
x₀ : R
⊢ Tendsto (fun x ↦ x * x₀) (𝓝 0) (𝓝 0)
Module: Mathlib.FieldTheory.Galois.Basic

Goal state before:
pp: F : Type u_1
inst✝⁴ : Field F
E : Type u_2
inst✝³ : Field E
inst✝² : Algebra F E
inst✝¹ : FiniteDimensional F E
inst✝ : IsGalois F E
α : E
h1 : F⟮α⟯ = ⊤
⊢ ∃ p, p.Separable ∧ Polynomial.IsSplittingField F E p

Tactic:
use minpoly F α, separable F α, IsGalois.splits F α

Goal state after:
case adjoin_rootSet'
F : Type u_1
inst✝⁴ : Field F
E : Type u_2
inst✝³ : Field E
inst✝² : Algebra F E
inst✝¹ : FiniteDimensional F E
inst✝ : IsGalois F E
α : E
h1 : F⟮α⟯ = ⊤
⊢ Algebra.adjoin F ((minpoly F α).rootSet E) = ⊤
Module: Mathlib.Topology.Algebra.FilterBasis

Goal state before:
pp: case hmulright
R : Type u_1
M : Type u_2
inst✝⁶ : Ring R
inst✝⁵ : TopologicalSpace R
inst✝⁴ : AddCommGroup M
inst✝³ : Module R M
ι : Type u_3
inst✝² : IsTopologicalRing R
inst✝¹ : TopologicalSpace M
inst✝ : IsTopologicalAddGroup M
p : ι → Prop
b : ι → Set M
h : (𝓝 0).HasBasis p b
hsmul : ∀ {i : ι}, p i → ∃ V ∈ 𝓝 0, ∃ j, p j ∧ V • b j ⊆ b i
hsmul_left : ∀ (x₀ : R) {i : ι}, p i → ∃ j, p j ∧ MapsTo (fun x ↦ x₀ • x) (b j) (b i)
hsmul_right : ∀ (m₀ : M) {i : ι}, p i → ∀ᶠ (x : R) in 𝓝 0, x • m₀ ∈ b i
⊢ ∀ (a : R), Tendsto (fun m ↦ a • m) (𝓝 0) (𝓝 0)

Tactic:
intro x₀

Goal state after:
case hmulright
R : Type u_1
M : Type u_2
inst✝⁶ : Ring R
inst✝⁵ : TopologicalSpace R
inst✝⁴ : AddCommGroup M
inst✝³ : Module R M
ι : Type u_3
inst✝² : IsTopologicalRing R
inst✝¹ : TopologicalSpace M
inst✝ : IsTopologicalAddGroup M
p : ι → Prop
b : ι → Set M
h : (𝓝 0).HasBasis p b
hsmul : ∀ {i : ι}, p i → ∃ V ∈ 𝓝 0, ∃ j, p j ∧ V • b j ⊆ b i
hsmul_left : ∀ (x₀ : R) {i : ι}, p i → ∃ j, p j ∧ MapsTo (fun x ↦ x₀ • x) (b j) (b i)
hsmul_right : ∀ (m₀ : M) {i : ι}, p i → ∀ᶠ (x : R) in 𝓝 0, x • m₀ ∈ b i
x₀ : R
⊢ Tendsto (fun m ↦ x₀ • m) (𝓝 0) (𝓝 0)
Module: Mathlib.FieldTheory.KrullTopology

Goal state before:
pp: case refine_2
K : Type u_1
L : Type u_2
inst✝² : Field K
inst✝¹ : Field L
inst✝ : Algebra K L
σ : Gal(L/K)
E : IntermediateField K L
hE : E ∈ finiteExts K L
F : IntermediateField K L := IntermediateField.map (↑σ.symm) E
g : Gal(L/K)
hg : g ∈ F.fixingSubgroup.carrier
x : L
hx : x ∈ E
h_in_F : σ⁻¹ x ∈ F
h_g_fix : g (σ⁻¹ x) = σ⁻¹ x
⊢ σ (g (σ⁻¹ x)) = x

Tactic:
h_g_fix

Goal state after:
case refine_2
K : Type u_1
L : Type u_2
inst✝² : Field K
inst✝¹ : Field L
inst✝ : Algebra K L
σ : Gal(L/K)
E : IntermediateField K L
hE : E ∈ finiteExts K L
F : IntermediateField K L := IntermediateField.map (↑σ.symm) E
g : Gal(L/K)
hg : g ∈ F.fixingSubgroup.carrier
x : L
hx : x ∈ E
h_in_F : σ⁻¹ x ∈ F
h_g_fix : g (σ⁻¹ x) = σ⁻¹ x
⊢ σ (σ⁻¹ x) = x
Module: Mathlib.FieldTheory.KrullTopology

Goal state before:
pp: case refine_2
K : Type u_1
L : Type u_2
inst✝² : Field K
inst✝¹ : Field L
inst✝ : Algebra K L
σ : Gal(L/K)
E : IntermediateField K L
hE : E ∈ finiteExts K L
F : IntermediateField K L := IntermediateField.map (↑σ.symm) E
g : Gal(L/K)
hg : g ∈ F.fixingSubgroup.carrier
x : L
hx : x ∈ E
h_in_F : σ⁻¹ x ∈ F
h_g_fix : g (σ⁻¹ x) = σ⁻¹ x
⊢ σ (σ⁻¹ x) = x

Tactic:
exact AlgEquiv.apply_symm_apply σ x

Goal state after:
Module: Mathlib.FieldTheory.KrullTopology

Goal state before:
pp: K : Type u_1
L : Type u_2
inst✝² : Field K
inst✝¹ : Field L
inst✝ : Algebra K L
⊢ ∀ (x₀ : Gal(L/K)) {U : Set Gal(L/K)},
    U ∈ (galBasis K L).sets → ∃ V ∈ (galBasis K L).sets, V ⊆ (fun x ↦ x₀ * x * x₀⁻¹) ⁻¹' U

Tactic:
rintro σ U ⟨H, ⟨E, hE, rfl⟩, rfl⟩
    let F : IntermediateField K L := E.map σ.symm.toAlgHom
    refine ⟨F.fixingSubgroup.carrier, ⟨⟨F.fixingSubgroup, ⟨F, ?_, rfl⟩, rfl⟩, fun g hg => ?_⟩⟩
    · have : FiniteDimensional K E := hE
      exact IntermediateField.finiteDimensional_map σ.symm.toAlgHom
    change σ * g * σ⁻¹ ∈ E.fixingSubgroup
    rw [IntermediateField.mem_fixingSubgroup_iff]
    intro x hx
    change σ (g (σ⁻¹ x)) = x
    have h_in_F : σ⁻¹ x ∈ F := ⟨x, hx, by dsimp⟩
    have h_g_fix : g (σ⁻¹ x) = σ⁻¹ x := by
      rw [Subgroup.mem_carrier, IntermediateField.mem_fixingSubgroup_iff F g] at hg
      exact hg (σ⁻¹ x) h_in_F
    rw [h_g_fix]
    change σ (σ⁻¹ x) = x
    exact AlgEquiv.apply_symm_apply σ x

Goal state after:
Module: Mathlib.LinearAlgebra.BilinearForm.DualLattice

Goal state before:
pp: case intro.a
R : Type u_4
S : Type u_2
M : Type u_3
inst✝⁸ : CommRing R
inst✝⁷ : Field S
inst✝⁶ : AddCommGroup M
inst✝⁵ : Algebra R S
inst✝⁴ : Module R M
inst✝³ : Module S M
inst✝² : IsScalarTower R S M
B : BilinForm S M
ι : Type u_1
inst✝¹ : Finite ι
inst✝ : DecidableEq ι
hB : B.Nondegenerate
b : Basis ι S M
val✝ : Fintype ι
x : M
hx : x ∈ B.dualSubmodule (Submodule.span R (Set.range ⇑b))
i : ι
r : R
hr : (algebraMap R S) r = (B x) (b i)
⊢ ((B.dualBasis hB b).repr x) i • (B.dualBasis hB b) i ∈ Submodule.span R (Set.range ⇑(B.dualBasis hB b))

Tactic:
simp only [dualBasis_repr_apply, ← hr, algebraMap_smul]

Goal state after:
case intro.a
R : Type u_4
S : Type u_2
M : Type u_3
inst✝⁸ : CommRing R
inst✝⁷ : Field S
inst✝⁶ : AddCommGroup M
inst✝⁵ : Algebra R S
inst✝⁴ : Module R M
inst✝³ : Module S M
inst✝² : IsScalarTower R S M
B : BilinForm S M
ι : Type u_1
inst✝¹ : Finite ι
inst✝ : DecidableEq ι
hB : B.Nondegenerate
b : Basis ι S M
val✝ : Fintype ι
x : M
hx : x ∈ B.dualSubmodule (Submodule.span R (Set.range ⇑b))
i : ι
r : R
hr : (algebraMap R S) r = (B x) (b i)
⊢ r • (B.dualBasis hB b) i ∈ Submodule.span R (Set.range ⇑(B.dualBasis hB b))
Module: Mathlib.LinearAlgebra.BilinearForm.DualLattice

Goal state before:
pp: R : Type u_4
S : Type u_2
M : Type u_3
inst✝⁸ : CommRing R
inst✝⁷ : Field S
inst✝⁶ : AddCommGroup M
inst✝⁵ : Algebra R S
inst✝⁴ : Module R M
inst✝³ : Module S M
inst✝² : IsScalarTower R S M
B : BilinForm S M
ι : Type u_1
inst✝¹ : Finite ι
inst✝ : DecidableEq ι
hB : B.Nondegenerate
b : Basis ι S M
⊢ B.dualSubmodule (Submodule.span R (Set.range ⇑b)) = Submodule.span R (Set.range ⇑(B.dualBasis hB b))

Tactic:
by
  cases nonempty_fintype ι
  apply le_antisymm
  · intro x hx
    rw [← (B.dualBasis hB b).sum_repr x]
    apply sum_mem
    rintro i -
    obtain ⟨r, hr⟩ := Submodule.mem_one.mp <| hx (b i) (Submodule.subset_span ⟨_, rfl⟩)
    simp only [dualBasis_repr_apply, ← hr, algebraMap_smul]
    apply Submodule.smul_mem
    exact Submodule.subset_span ⟨_, rfl⟩
  · rw [Submodule.span_le]
    rintro _ ⟨i, rfl⟩ y hy
    obtain ⟨f, rfl⟩ := (Submodule.mem_span_range_iff_exists_fun _).mp hy
    simp only [map_sum]
    apply sum_mem
    rintro j -
    rw [← IsScalarTower.algebraMap_smul S (f j), map_smul]
    simp_rw [apply_dualBasis_left]
    rw [smul_eq_mul, mul_ite, mul_one, mul_zero, ← (algebraMap R S).map_zero, ← apply_ite]
    exact Submodule.mem_one.mpr ⟨_, rfl⟩

Goal state after:
Module: Mathlib.FieldTheory.Galois.Infinite

Goal state before:
pp: k : Type u_1
K : Type u_2
inst✝³ : Field k
inst✝² : Field K
inst✝¹ : Algebra k K
H : ClosedSubgroup Gal(K/k)
inst✝ : IsGalois k K
σ : Gal(K/k)
hσ : σ ∈ (fixedField ↑H).fixingSubgroup
h : σ ∉ ↑H
⊢ False

Tactic:
have nhds : H.carrierᶜ ∈ nhds σ := H.isClosed'.isOpen_compl.mem_nhds h

Goal state after:
k : Type u_1
K : Type u_2
inst✝³ : Field k
inst✝² : Field K
inst✝¹ : Algebra k K
H : ClosedSubgroup Gal(K/k)
inst✝ : IsGalois k K
σ : Gal(K/k)
hσ : σ ∈ (fixedField ↑H).fixingSubgroup
h : σ ∉ ↑H
nhds : (↑H).carrierᶜ ∈ _root_.nhds σ
⊢ False