mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Dynamics.TopologicalEntropy.Semiconj

Goal state before:
pp: X : Type u_1
Y : Type u_2
u : UniformSpace Y
S : X → X
T : Y → Y
φ : X → Y
h : Semiconj φ S T
F : Set X
⊢ coverEntropy T (φ '' F) = coverEntropy S F

Tactic:
by
  let : UniformSpace X := comap φ u
  apply le_antisymm
  · refine iSup₂_le fun V V_uni ↦
      (coverEntropyEntourage_antitone _ _ SetRel.symmetrize_subset_self).trans <|
      (coverEntropyEntourage_image_le h F _).trans ?_
    apply coverEntropyEntourage_le_coverEntropy
    rw [uniformity_comap φ, mem_comap]
    exact ⟨_, symmetrize_mem_uniformity V_uni, .rfl⟩
  · refine iSup₂_le fun U U_uni ↦ ?_
    simp only [uniformity_comap φ, mem_comap] at U_uni
    obtain ⟨V, V_uni, V_sub⟩ := U_uni
    obtain ⟨W, W_uni, W_symm, W_V⟩ := comp_symm_mem_uniformity_sets V_uni
    apply (coverEntropyEntourage_antitone S F ((preimage_mono W_V).trans V_sub)).trans
    apply (le_coverEntropyEntourage_image h F).trans
    exact coverEntropyEntourage_le_coverEntropy T (φ '' F) W_uni

Goal state after:
Module: Mathlib.MeasureTheory.Measure.Decomposition.RadonNikodym

Goal state before:
pp: α : Type u_1
m : MeasurableSpace α
μ ν : Measure α
inst✝¹ : SigmaFinite μ
inst✝ : SigmaFinite ν
hν_ac : μ ≪ ν + μ
a : α
h1 : (ν + μ).rnDeriv μ a = (ν.rnDeriv μ + μ.rnDeriv μ) a
h2 : μ.rnDeriv μ a = 1
⊢ (μ.rnDeriv (ν + μ))⁻¹ a = (ν + μ).rnDeriv μ a → μ.rnDeriv (ν + μ) a = (ν.rnDeriv μ a + 1)⁻¹

Tactic:
h3

Goal state after:
α : Type u_1
m : MeasurableSpace α
μ ν : Measure α
inst✝¹ : SigmaFinite μ
inst✝ : SigmaFinite ν
hν_ac : μ ≪ ν + μ
a : α
h1 : (ν + μ).rnDeriv μ a = (ν.rnDeriv μ + μ.rnDeriv μ) a
h2 : μ.rnDeriv μ a = 1
h3 : (μ.rnDeriv (ν + μ))⁻¹ a = (ν + μ).rnDeriv μ a
⊢ μ.rnDeriv (ν + μ) a = (ν.rnDeriv μ a + 1)⁻¹
Module: Mathlib.MeasureTheory.Measure.Decomposition.RadonNikodym

Goal state before:
pp: α : Type u_1
m : MeasurableSpace α
μ ν : Measure α
inst✝¹ : SigmaFinite μ
inst✝ : SigmaFinite ν
hν_ac : μ ≪ ν + μ
a : α
h1 : (ν + μ).rnDeriv μ a = (ν.rnDeriv μ + μ.rnDeriv μ) a
h2 : μ.rnDeriv μ a = 1
h3 : μ.rnDeriv (ν + μ) a = (ν.rnDeriv μ a + 1)⁻¹
⊢ μ.rnDeriv (ν + μ) a = (ν.rnDeriv μ a + 1)⁻¹

Tactic:
h3

Goal state after:
α : Type u_1
m : MeasurableSpace α
μ ν : Measure α
inst✝¹ : SigmaFinite μ
inst✝ : SigmaFinite ν
hν_ac : μ ≪ ν + μ
a : α
h1 : (ν + μ).rnDeriv μ a = (ν.rnDeriv μ + μ.rnDeriv μ) a
h2 : μ.rnDeriv μ a = 1
h3 : μ.rnDeriv (ν + μ) a = (ν.rnDeriv μ a + 1)⁻¹
⊢ (ν.rnDeriv μ a + 1)⁻¹ = (ν.rnDeriv μ a + 1)⁻¹
Module: Mathlib.Dynamics.TopologicalEntropy.Subset

Goal state before:
pp: case inr.inr
X : Type u_1
T : X → X
F G : Set X
U : SetRel X X
n : ℕ
hF : coverMincard T F U n < ⊤
hG : coverMincard T G U n < ⊤
s : Finset X
s_cover : IsDynCoverOf T F U n ↑s
s_coverMincard : ↑s.card = coverMincard T F U n
t : Finset X
t_cover : IsDynCoverOf T G U n ↑t
t_coverMincard : ↑t.card = coverMincard T G U n
⊢ coverMincard T (F ∪ G) U n ≤ coverMincard T F U n + coverMincard T G U n

Tactic:
← s_coverMincard,

Goal state after:
case inr.inr
X : Type u_1
T : X → X
F G : Set X
U : SetRel X X
n : ℕ
hF : coverMincard T F U n < ⊤
hG : coverMincard T G U n < ⊤
s : Finset X
s_cover : IsDynCoverOf T F U n ↑s
s_coverMincard : ↑s.card = coverMincard T F U n
t : Finset X
t_cover : IsDynCoverOf T G U n ↑t
t_coverMincard : ↑t.card = coverMincard T G U n
⊢ coverMincard T (F ∪ G) U n ≤ ↑s.card + coverMincard T G U n
Module: Mathlib.MeasureTheory.Measure.Decomposition.RadonNikodym

Goal state before:
pp: α : Type u_1
m : MeasurableSpace α
μ ν ξ : Measure α
inst✝² : SigmaFinite μ
inst✝¹ : SigmaFinite ν
inst✝ : SigmaFinite ξ
hμ : μ ≪ ξ
hν : ν ≪ ξ
h1 : μ.rnDeriv (μ + ν) * (μ + ν).rnDeriv ξ =ᵐ[ξ] μ.rnDeriv ξ
h2 : ν.rnDeriv (μ + ν) * (μ + ν).rnDeriv ξ =ᵐ[ξ] ν.rnDeriv ξ
h_ac : μ + ν ≪ ξ
⊢ (fun x ↦ μ.rnDeriv ξ x / ν.rnDeriv ξ x) =ᵐ[μ + ν] fun x ↦ μ.rnDeriv (μ + ν) x / ν.rnDeriv (μ + ν) x

Tactic:
filter_upwards [h_ac h1, h_ac h2, h_ac <| (μ + ν).rnDeriv_lt_top ξ, ν.rnDeriv_lt_top (μ + ν),
    Measure.rnDeriv_pos h_ac] with a h1 h2 h_lt_top1 h_lt_top2 h_pos

Goal state after:
α : Type u_1
m : MeasurableSpace α
μ ν ξ : Measure α
inst✝² : SigmaFinite μ
inst✝¹ : SigmaFinite ν
inst✝ : SigmaFinite ξ
hμ : μ ≪ ξ
hν : ν ≪ ξ
h1✝ : μ.rnDeriv (μ + ν) * (μ + ν).rnDeriv ξ =ᵐ[ξ] μ.rnDeriv ξ
h2✝ : ν.rnDeriv (μ + ν) * (μ + ν).rnDeriv ξ =ᵐ[ξ] ν.rnDeriv ξ
h_ac : μ + ν ≪ ξ
a : α
h1 : (μ.rnDeriv (μ + ν) * (μ + ν).rnDeriv ξ) a = μ.rnDeriv ξ a
h2 : (ν.rnDeriv (μ + ν) * (μ + ν).rnDeriv ξ) a = ν.rnDeriv ξ a
h_lt_top1 : (μ + ν).rnDeriv ξ a < ∞
h_lt_top2 : ν.rnDeriv (μ + ν) a < ∞
h_pos : 0 < (μ + ν).rnDeriv ξ a
⊢ μ.rnDeriv ξ a / ν.rnDeriv ξ a = μ.rnDeriv (μ + ν) a / ν.rnDeriv (μ + ν) a
Module: Mathlib.FieldTheory.AbelRuffini

Goal state before:
pp: F : Type u_3
inst✝¹ : Field F
E : Type u_4
inst✝ : Field E
i : F →+* E
n : ℕ
a : F
ha : a ≠ 0
h : (map i (X ^ n - C a)).Splits
ha' : i a ≠ 0
hn : ¬n = 0
hn' : 0 < n
hn'' : (X ^ n - C a).degree ≠ 0
b : E
hb : b ^ n = i a
hb' : b ≠ 0
s : Multiset E := (map i (X ^ n - C a)).roots
hs : map i (X ^ n - C a) = (Multiset.map (fun x ↦ X - C x) s).prod
⊢ s.card = n

Tactic:
← h.natDegree_eq_card_roots,

Goal state after:
F : Type u_3
inst✝¹ : Field F
E : Type u_4
inst✝ : Field E
i : F →+* E
n : ℕ
a : F
ha : a ≠ 0
h : (map i (X ^ n - C a)).Splits
ha' : i a ≠ 0
hn : ¬n = 0
hn' : 0 < n
hn'' : (X ^ n - C a).degree ≠ 0
b : E
hb : b ^ n = i a
hb' : b ≠ 0
s : Multiset E := (map i (X ^ n - C a)).roots
hs : map i (X ^ n - C a) = (Multiset.map (fun x ↦ X - C x) s).prod
⊢ (map i (X ^ n - C a)).natDegree = n
Module: Mathlib.FieldTheory.AbelRuffini

Goal state before:
pp: F : Type u_1
E : Type u_2
inst✝² : Field F
inst✝¹ : Field E
inst✝ : Algebra F E
motive : (x : E) → x ∈ solvableByRad F E → Prop
mem : ∀ (x : F), motive ((algebraMap F E) x) ⋯
add :
  ∀ (x y : E) (hx : x ∈ solvableByRad F E) (hy : y ∈ solvableByRad F E), motive x hx → motive y hy → motive (x + y) ⋯
mul :
  ∀ (x y : E) (hx : x ∈ solvableByRad F E) (hy : y ∈ solvableByRad F E), motive x hx → motive y hy → motive (x * y) ⋯
rad : ∀ (n : ℕ) (x : E) (hn : n ≠ 0) (hx : x ^ n ∈ solvableByRad F E), motive (x ^ n) hx → motive x ⋯
x : E
hx : x ∈ solvableByRad F E
s : Subalgebra F E :=
  { carrier := {x | ∃ (hx : x ∈ solvableByRad F E), motive x hx}, mul_mem' := ⋯, one_mem' := ⋯, add_mem' := ⋯,
    zero_mem' := ⋯, algebraMap_mem' := ⋯ }
⊢ motive x hx

Tactic:
let t : IntermediateField F E := Subalgebra.IsAlgebraic.toIntermediateField (S := s) <| by
    rintro x ⟨hx, hx'⟩
    apply isAlgebraic_solvableByRad
    exact hx

Goal state after:
F : Type u_1
E : Type u_2
inst✝² : Field F
inst✝¹ : Field E
inst✝ : Algebra F E
motive : (x : E) → x ∈ solvableByRad F E → Prop
mem : ∀ (x : F), motive ((algebraMap F E) x) ⋯
add :
  ∀ (x y : E) (hx : x ∈ solvableByRad F E) (hy : y ∈ solvableByRad F E), motive x hx → motive y hy → motive (x + y) ⋯
mul :
  ∀ (x y : E) (hx : x ∈ solvableByRad F E) (hy : y ∈ solvableByRad F E), motive x hx → motive y hy → motive (x * y) ⋯
rad : ∀ (n : ℕ) (x : E) (hn : n ≠ 0) (hx : x ^ n ∈ solvableByRad F E), motive (x ^ n) hx → motive x ⋯
x : E
hx : x ∈ solvableByRad F E
s : Subalgebra F E :=
  { carrier := {x | ∃ (hx : x ∈ solvableByRad F E), motive x hx}, mul_mem' := ⋯, one_mem' := ⋯, add_mem' := ⋯,
    zero_mem' := ⋯, algebraMap_mem' := ⋯ }
t : IntermediateField F E := Subalgebra.IsAlgebraic.toIntermediateField ⋯
⊢ motive x hx
Module: Mathlib.ModelTheory.Syntax

Goal state before:
pp: case func
L : Language
α : Type u'
l✝ : ℕ
_f✝ : L.Functions l✝
_ts✝ : Fin l✝ → L.Term α
ih : ∀ (a : Fin l✝), (LHom.id L).onTerm (_ts✝ a) = id (_ts✝ a)
⊢ (LHom.id L).onTerm (func _f✝ _ts✝) = id (func _f✝ _ts✝)

Tactic:
onTerm,

Goal state after:
case func
L : Language
α : Type u'
l✝ : ℕ
_f✝ : L.Functions l✝
_ts✝ : Fin l✝ → L.Term α
ih : ∀ (a : Fin l✝), (LHom.id L).onTerm (_ts✝ a) = id (_ts✝ a)
⊢ (func ((LHom.id L).onFunction _f✝) fun i ↦ (LHom.id L).onTerm (_ts✝ i)) = id (func _f✝ _ts✝)
Module: Mathlib.ModelTheory.Syntax

Goal state before:
pp: case func
L : Language
L' : Language
α : Type u'
L'' : Language
φ : L' →ᴸ L''
ψ : L →ᴸ L'
l✝ : ℕ
_f✝ : L.Functions l✝
_ts✝ : Fin l✝ → L.Term α
ih : ∀ (a : Fin l✝), (φ.comp ψ).onTerm (_ts✝ a) = (φ.onTerm ∘ ψ.onTerm) (_ts✝ a)
⊢ (φ.comp ψ).onTerm (func _f✝ _ts✝) = (φ.onTerm ∘ ψ.onTerm) (func _f✝ _ts✝)

Tactic:
onTerm,

Goal state after:
case func
L : Language
L' : Language
α : Type u'
L'' : Language
φ : L' →ᴸ L''
ψ : L →ᴸ L'
l✝ : ℕ
_f✝ : L.Functions l✝
_ts✝ : Fin l✝ → L.Term α
ih : ∀ (a : Fin l✝), (φ.comp ψ).onTerm (_ts✝ a) = (φ.onTerm ∘ ψ.onTerm) (_ts✝ a)
⊢ (func ((φ.comp ψ).onFunction _f✝) fun i ↦ (φ.comp ψ).onTerm (_ts✝ i)) = (φ.onTerm ∘ ψ.onTerm) (func _f✝ _ts✝)
Module: Mathlib.ModelTheory.Syntax

Goal state before:
pp: case all
L : Language
α : Type u'
n n✝ : ℕ
f✝ : L.BoundedFormula α (n✝ + 1)
ih3 : ∀ (h : n✝ + 1 ≤ n✝ + 1), castLE h f✝ = f✝
h : n✝ ≤ n✝
⊢ castLE h f✝.all = f✝.all

Tactic:
simp [ih3]

Goal state after:
Module: Mathlib.ModelTheory.Syntax

Goal state before:
pp: case falsum
L : Language
α : Type u'
k n✝ : ℕ
⊢ ∀ {m n : ℕ} (km : n✝ ≤ m) (mn : m ≤ n), castLE mn (castLE km falsum) = castLE ⋯ falsum

Tactic:
intros; rfl

Goal state after:
Module: Mathlib.ModelTheory.Syntax

Goal state before:
pp: L : Language
α : Type u'
s t : Set α
h : s ⊆ t
⊢ L.distinctConstantsTheory s ⊆ L.distinctConstantsTheory t

Tactic:
by
  unfold distinctConstantsTheory; gcongr

Goal state after:
Module: Mathlib.ModelTheory.Ultraproducts

Goal state before:
pp: case refine_2
α : Type u_1
M : α → Type u_2
u : Ultrafilter α
L : Language
inst✝ : (a : α) → L.Structure (M a)
n : ℕ
r : L.Relations n
x y : Fin n → (a : α) → M a
xy : x ≈ y
hy : ∀ᶠ (a : α) in ↑u, RelMap r fun i ↦ y i a
a : α
ha1 : RelMap r fun i ↦ y i a
ha2 : ∀ (i : Fin n), x i a = y i a
⊢ RelMap r fun i ↦ x i a

Tactic:
funext ha2

Goal state after:
case refine_2
α : Type u_1
M : α → Type u_2
u : Ultrafilter α
L : Language
inst✝ : (a : α) → L.Structure (M a)
n : ℕ
r : L.Relations n
x y : Fin n → (a : α) → M a
xy : x ≈ y
hy : ∀ᶠ (a : α) in ↑u, RelMap r fun i ↦ y i a
a : α
ha1 : RelMap r fun i ↦ y i a
ha2 : ∀ (i : Fin n), x i a = y i a
⊢ RelMap r fun x ↦ y x a
Module: Mathlib.ModelTheory.Ultraproducts

Goal state before:
pp: case all.h₂.refine_2
α : Type u_1
M : α → Type u_2
u : Ultrafilter α
L : Language
inst✝¹ : (a : α) → L.Structure (M a)
inst✝ : ∀ (a : α), Nonempty (M a)
β : Type u_3
n : ℕ
x : β → (a : α) → M a
k : ℕ
φ : L.BoundedFormula β (k + 1)
ih :
  ∀ (v : Fin (k + 1) → (a : α) → M a),
    (φ.Realize (fun i ↦ Quotient.mk' (x i)) fun i ↦ Quotient.mk' (v i)) ↔
      ∀ᶠ (a : α) in ↑u, φ.Realize (fun i ↦ x i a) fun i ↦ v i a
v : Fin k → (a : α) → M a
h' : ∀ (m : (a : α) → M a) (a : α), (fun i ↦ Fin.snoc v m i a) = Fin.snoc (fun i ↦ v i a) (m a)
h : ∀ᶠ (a : α) in ↑u, ∀ (x_1 : M a), φ.Realize (fun i ↦ x i a) (Fin.snoc (fun i ↦ v i a) x_1)
m : (a : α) → M a
⊢ ∀ᶠ (a : α) in ↑u, φ.Realize (fun i ↦ x i a) (Fin.snoc (fun i ↦ v i a) (m a))

Tactic:
· rw [Filter.eventually_iff] at *
      exact Filter.mem_of_superset h fun a ha => ha (m a)

Goal state after:
Module: Mathlib.ModelTheory.Semantics

Goal state before:
pp: L : Language
M : Type w
inst✝ : L.Structure M
α : Type u'
β : Type v'
φ : L.Formula α
g : α → β
v : β → M
⊢ BoundedFormula.Realize φ (Sum.elim v (default ∘ castAdd 0) ∘ Sum.inl ∘ g) (default ∘ natAdd 0) =
    BoundedFormula.Realize φ (v ∘ g) default

Tactic:
Fin.castAdd_zero

Goal state after:
L : Language
M : Type w
inst✝ : L.Structure M
α : Type u'
β : Type v'
φ : L.Formula α
g : α → β
v : β → M
⊢ BoundedFormula.Realize φ (Sum.elim v (default ∘ Fin.cast ⋯) ∘ Sum.inl ∘ g) (default ∘ natAdd 0) =
    BoundedFormula.Realize φ (v ∘ g) default
Module: Mathlib.ModelTheory.Definability

Goal state before:
pp: M : Type w
A : Set M
L : Language
inst✝ : L.Structure M
α : Type u₁
β : Type u_1
f : α → β
φ : L[[↑A]].Formula α
⊢ A.Definable L ((fun g ↦ g ∘ f) ⁻¹' ofPred φ.Realize)

Tactic:
refine ⟨φ.relabel f, ?_⟩

Goal state after:
M : Type w
A : Set M
L : Language
inst✝ : L.Structure M
α : Type u₁
β : Type u_1
f : α → β
φ : L[[↑A]].Formula α
⊢ (fun g ↦ g ∘ f) ⁻¹' ofPred φ.Realize = ofPred (Formula.relabel f φ).Realize
Module: Mathlib.ModelTheory.Encoding

Goal state before:
pp: case imp
L : Language
α : Type u'
l✝ : List ((n : ℕ) × L.BoundedFormula α n)
n n✝ : ℕ
f₁✝ f₂✝ : L.BoundedFormula α n✝
ih1 :
  ∀ (l' : List ((k : ℕ) × L.Term (α ⊕ Fin k) ⊕ (n : ℕ) × L.Relations n ⊕ ℕ)),
    listDecode (f₁✝.listEncode ++ l') = ⟨n✝, f₁✝⟩ :: listDecode l'
ih2 :
  ∀ (l' : List ((k : ℕ) × L.Term (α ⊕ Fin k) ⊕ (n : ℕ) × L.Relations n ⊕ ℕ)),
    listDecode (f₂✝.listEncode ++ l') = ⟨n✝, f₂✝⟩ :: listDecode l'
l : List ((k : ℕ) × L.Term (α ⊕ Fin k) ⊕ (n : ℕ) × L.Relations n ⊕ ℕ)
⊢ (if h : 2 ≤ (listDecode (f₁✝.listEncode ++ (f₂✝.listEncode ++ l))).length then
      sigmaImp (listDecode (f₁✝.listEncode ++ (f₂✝.listEncode ++ l)))[0]
          (listDecode (f₁✝.listEncode ++ (f₂✝.listEncode ++ l)))[1] ::
        drop 2 (listDecode (f₁✝.listEncode ++ (f₂✝.listEncode ++ l)))
    else []) =
    ⟨n✝, f₁✝ ⟹ f₂✝⟩ :: listDecode l

Tactic:
simp only [ih1, ih2, length_cons, le_add_iff_nonneg_left, _root_.zero_le, ↓reduceDIte,
      getElem_cons_zero, getElem_cons_succ, sigmaImp_apply, drop_succ_cons, drop_zero]

Goal state after:
Module: Mathlib.ModelTheory.Satisfiability

Goal state before:
pp: case inl
L : Language
T : L.Theory
h : T.IsComplete
φ : L.Sentence
hφ : T ⊨ᵇ φ
⊢ T ⊨ᵇ Formula.not φ ↔ ¬T ⊨ᵇ φ

Tactic:
simp only [hφ, not_true, iff_false]
    rw [models_sentence_iff, not_forall]
    refine ⟨h.1.some, ?_⟩
    simp only [Sentence.realize_not, Classical.not_not]
    exact models_sentence_iff.1 hφ _

Goal state after:
Module: Mathlib.LinearAlgebra.FreeAlgebra

Goal state before:
pp: R : Type u
X : Type v
inst✝¹ : CommRing R
inst✝ : Nontrivial R
⊢ Module.rank R (FreeAlgebra R X) = Cardinal.lift.{u, v} (Cardinal.mk (List X))

Tactic:
rw [← (Basis.mk_eq_rank'.{_, _, _, u} (basisFreeMonoid R X)).trans (Cardinal.lift_id _),
    Cardinal.lift_umax.{v, u}, FreeMonoid]

Goal state after:
Module: Mathlib.SetTheory.Cardinal.Divisibility

Goal state before:
pp: case refine_2.inr
a : Cardinal.{u}
ha : ℵ₀ ≤ a
b c : Cardinal.{u}
hbc : a ∣ b * c
hz : b * c ≠ 0
⊢ a ∣ b ∨ a ∣ c

Tactic:
wlog h : c ≤ b

Goal state after:
case refine_2.inr.inr
a : Cardinal.{u}
ha : ℵ₀ ≤ a
b c : Cardinal.{u}
hbc : a ∣ b * c
hz : b * c ≠ 0
this : ∀ {a : Cardinal.{u}}, ℵ₀ ≤ a → ∀ (b c : Cardinal.{u}), a ∣ b * c → b * c ≠ 0 → c ≤ b → a ∣ b ∨ a ∣ c
h : ¬c ≤ b
⊢ a ∣ b ∨ a ∣ c

a✝ a : Cardinal.{u}
ha : ℵ₀ ≤ a
b c : Cardinal.{u}
hbc : a ∣ b * c
hz : b * c ≠ 0
h : c ≤ b
⊢ a ∣ b ∨ a ∣ c
Module: Mathlib.FieldTheory.FinTrdeg

Goal state before:
pp: K : Type u_3
E : Type u_4
L : Type u_5
inst✝⁸ : Field K
inst✝⁷ : Field E
inst✝⁶ : Field L
inst✝⁵ : Algebra K E
inst✝⁴ : Algebra K L
inst✝³ : Algebra E L
inst✝² : IsScalarTower K E L
inst✝¹ : FinTrdeg K E
inst✝ : FinTrdeg E L
⊢ Cardinal.lift.{u_5, u_4} (Algebra.trdeg K E) + Cardinal.lift.{u_4, u_5} (Algebra.trdeg E L) < Cardinal.aleph0

Tactic:
Cardinal.add_lt_aleph0_iff,

Goal state after:
K : Type u_3
E : Type u_4
L : Type u_5
inst✝⁸ : Field K
inst✝⁷ : Field E
inst✝⁶ : Field L
inst✝⁵ : Algebra K E
inst✝⁴ : Algebra K L
inst✝³ : Algebra E L
inst✝² : IsScalarTower K E L
inst✝¹ : FinTrdeg K E
inst✝ : FinTrdeg E L
⊢ Cardinal.lift.{u_5, u_4} (Algebra.trdeg K E) < Cardinal.aleph0 ∧
    Cardinal.lift.{u_4, u_5} (Algebra.trdeg E L) < Cardinal.aleph0
Module: Mathlib.FieldTheory.Finite.Extension

Goal state before:
pp: k : Type u_1
inst✝⁶ : Field k
inst✝⁵ : Finite k
p : ℕ
inst✝⁴ : Fact (Nat.Prime p)
inst✝³ : CharP k p
l : Type u_2
inst✝² : Field l
inst✝¹ : Algebra k l
inst✝ : Finite l
g : Gal(l/k)
⊢ ∃ i, ∀ (x : l), g x = x ^ Nat.card k ^ i

Tactic:
let n := Module.finrank k l
  have : NeZero n := NeZero.of_pos Module.finrank_pos
  obtain ⟨i, _, hi⟩ := Extension.exists_frob_pow_eq k p n <|
    (algEquivExtension k p n l rfl).symm.trans (g.trans (algEquivExtension k p n l rfl))
  refine ⟨i, fun x ↦ ?_⟩
  simpa using (AlgEquiv.congr_arg (f := (algEquivExtension k p n l rfl).symm) <|
    AlgEquiv.congr_fun hi (algEquivExtension k p n l rfl x)).symm

Goal state after:
Module: Mathlib.FieldTheory.Finite.Extension

Goal state before:
pp: case inr.inl
k : Type u_1
inst✝ : Field k
f : k[X]
hi : Irreducible f
n : ℕ
h : f ∣ X ^ Nat.card k ^ n - X
hn : n ≠ 0
h✝ : Finite k
p : ℕ
hp : CharP k p
this : Fact (Nat.Prime p)
⊢ f.natDegree ∣ n

Tactic:
have : NeZero n := ⟨hn⟩

Goal state after:
case inr.inl
k : Type u_1
inst✝ : Field k
f : k[X]
hi : Irreducible f
n : ℕ
h : f ∣ X ^ Nat.card k ^ n - X
hn : n ≠ 0
h✝ : Finite k
p : ℕ
hp : CharP k p
this✝ : Fact (Nat.Prime p)
this : NeZero n
⊢ f.natDegree ∣ n
Module: Mathlib.FieldTheory.Differential.Liouville

Goal state before:
pp: F : Type u_1
K : Type u_2
inst✝¹² : Field F
inst✝¹¹ : Field K
inst✝¹⁰ : Differential F
inst✝⁹ : Differential K
inst✝⁸ : Algebra F K
inst✝⁷ : DifferentialAlgebra F K
A : Type u_3
inst✝⁶ : Field A
inst✝⁵ : Algebra K A
inst✝⁴ : Algebra F A
inst✝³ : Differential A
inst✝² : IsScalarTower F K A
inst✝¹ : ContainConstants F K
inst1 : IsLiouville F K
inst2 : IsLiouville K A
a : F
ι : Type
inst✝ : Fintype ι
c : ι → F
hc : ∀ (x : ι), (c x)′ = 0
u : ι → A
v : A
h : ↑a = ∑ x, ↑(c x) * logDeriv (u x) + v′
⊢ ↑↑a = ∑ x, ↑((Algebra.cast ∘ c) x) * logDeriv (((fun x ↦ x) ∘ u) x) + v′

Tactic:
simpa only [Function.comp_apply, ← IsScalarTower.algebraMap_apply]

Goal state after:
Module: Mathlib.FieldTheory.Differential.Liouville

Goal state before:
pp: F : Type u_1
K : Type u_2
inst✝⁹ : Field F
inst✝⁸ : Field K
inst✝⁷ : Differential F
inst✝⁶ : Differential K
inst✝⁵ : Algebra F K
inst✝⁴ : DifferentialAlgebra F K
inst✝³ : CharZero F
inst✝² : FiniteDimensional F K
inst✝¹ : IsGalois F K
a : F
ι : Type
inst✝ : Fintype ι
c : ι → F
hc : ∀ (x : ι), (c x)′ = 0
u : ι → K
v : K
h : ↑a = ∑ x, ↑(c x) * logDeriv (u x) + v′
this : CharZero K
ffb : fixedField ⊤ = ⊥
| (algebraMap F K) a * ↑(Fintype.card Gal(K/F)) = ∑ x, ↑(c x) * logDeriv (∏ x_1, x_1 (u x)) + ∑ x, (x v)′

Tactic:
enter [2, 1, 2, i, 2]
        equals ∑ x : K ≃ₐ[F] K, logDeriv (x (u i)) =>
          by_cases h : u i = 0 <;>
          simp [logDeriv_prod, h]

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

Goal state before:
pp: k✝ : Type u_1
K✝ : Type u_2
inst✝⁵ : Field k✝
inst✝⁴ : Field K✝
inst✝³ : Algebra k✝ K✝
k : Type u_3
K : Type u_4
inst✝² : Field k
inst✝¹ : Field K
inst✝ : Algebra k K
⊢ ⟨fun L ↦ (AlgEquiv.restrictNormalHom ↥(unop L).toIntermediateField) 1, ⋯⟩ = 1

Tactic:
simp only [map_one]

Goal state after:
k✝ : Type u_1
K✝ : Type u_2
inst✝⁵ : Field k✝
inst✝⁴ : Field K✝
inst✝³ : Algebra k✝ K✝
k : Type u_3
K : Type u_4
inst✝² : Field k
inst✝¹ : Field K
inst✝ : Algebra k K
⊢ ⟨fun L ↦ 1, ⋯⟩ = 1
Module: Mathlib.FieldTheory.IsPerfectClosure

Goal state before:
pp: K : Type u_1
L : Type u_2
M : Type u_3
inst✝⁴ : CommSemiring K
inst✝³ : CommSemiring L
inst✝² : CommSemiring M
i : K →+* L
f : L →+* M
p : ℕ
inst✝¹ : IsPRadical i p
inst✝ : IsPRadical f p
x : K
h : i x ∈ RingHom.ker f
⊢ x ∈ pNilradical K p

Tactic:
simpa only [← Ideal.mem_comap, comap_pNilradical] using ker_le f p h

Goal state after:
Module: Mathlib.FieldTheory.IsRealClosed.Basic

Goal state before:
pp: R : Type u
inst✝¹ : Field R
inst✝ : IsRealClosed R
x : R
n : ℕ
hk : Odd ↑n
⊢ Odd n

Tactic:
simpa using hk

Goal state after:
Module: Mathlib.FieldTheory.IsRealClosed.Basic

Goal state before:
pp: R : Type u
inst✝¹ : Field R
inst✝ : IsRealClosed R
x : R
n : ℕ
hk : Odd (-↑n)
⊢ Odd ?m.72

Tactic:
simpa using hk

Goal state after:
Module: Mathlib.FieldTheory.IsRealClosed.Basic

Goal state before:
pp: R : Type u
inst✝¹ : Field R
inst✝ : IsRealClosed R
x : R
hx : IsSquare x
n : ℕ
hk : ↑n ≠ 0
⊢ n ≠ 0

Tactic:
simpa using hk

Goal state after:
Module: Mathlib.FieldTheory.IsRealClosed.Basic

Goal state before:
pp: R : Type u
inst✝¹ : Field R
inst✝ : IsRealClosed R
x : R
hx : IsSquare x
n : ℕ
hk : -↑n ≠ 0
⊢ ?m.78 ≠ 0

Tactic:
simpa using hk

Goal state after:
Module: Mathlib.FieldTheory.PerfectClosure

Goal state before:
pp: case mk.mk
K : Type u
inst✝⁵ : CommRing K
p : ℕ
inst✝⁴ : Fact (Nat.Prime p)
inst✝³ : CharP K p
L : Type v
inst✝² : CommSemiring L
inst✝¹ : CharP L p
inst✝ : PerfectRing L p
f : K →+* L
x✝ : PerfectClosure K p
n : ℕ
x : K
y✝ : PerfectClosure K p
m : ℕ
y : K
this : ∀ (n : ℕ), LeftInverse (⇑(frobeniusEquiv L p).symm)^[n] (⇑(frobenius L p))^[n]
⊢ (⇑(frobeniusEquiv L p).symm)^[n] (f x) *
      (⇑(frobeniusEquiv L p).symm)^[m] ((⇑(frobeniusEquiv L p).symm)^[n] ((⇑(frobenius L p))^[n] (f y))) =
    (⇑(frobeniusEquiv L p).symm)^[n] (f x) * (⇑(frobeniusEquiv L p).symm)^[m] (f y)

Tactic:
this _ _

Goal state after:
case mk.mk
K : Type u
inst✝⁵ : CommRing K
p : ℕ
inst✝⁴ : Fact (Nat.Prime p)
inst✝³ : CharP K p
L : Type v
inst✝² : CommSemiring L
inst✝¹ : CharP L p
inst✝ : PerfectRing L p
f : K →+* L
x✝ : PerfectClosure K p
n : ℕ
x : K
y✝ : PerfectClosure K p
m : ℕ
y : K
this : ∀ (n : ℕ), LeftInverse (⇑(frobeniusEquiv L p).symm)^[n] (⇑(frobenius L p))^[n]
⊢ (⇑(frobeniusEquiv L p).symm)^[n] (f x) * (⇑(frobeniusEquiv L p).symm)^[m] (f y) =
    (⇑(frobeniusEquiv L p).symm)^[n] (f x) * (⇑(frobeniusEquiv L p).symm)^[m] (f y)
Module: Mathlib.FieldTheory.PerfectClosure

Goal state before:
pp: case mk.mk
K : Type u
inst✝⁵ : CommRing K
p : ℕ
inst✝⁴ : Fact (Nat.Prime p)
inst✝³ : CharP K p
L : Type v
inst✝² : CommSemiring L
inst✝¹ : CharP L p
inst✝ : PerfectRing L p
f : K →+* L
x✝ : PerfectClosure K p
n : ℕ
x : K
y✝ : PerfectClosure K p
m : ℕ
y : K
this : ∀ (n : ℕ), LeftInverse (⇑(frobeniusEquiv L p).symm)^[n] (⇑(frobenius L p))^[n]
⊢ (⇑(frobeniusEquiv L p).symm)^[n] (f x) +
      (⇑(frobeniusEquiv L p).symm)^[m] ((⇑(frobeniusEquiv L p).symm)^[n] ((⇑(frobenius L p))^[n] (f y))) =
    (⇑(frobeniusEquiv L p).symm)^[n] (f x) + (⇑(frobeniusEquiv L p).symm)^[m] (f y)

Tactic:
this _ _

Goal state after:
case mk.mk
K : Type u
inst✝⁵ : CommRing K
p : ℕ
inst✝⁴ : Fact (Nat.Prime p)
inst✝³ : CharP K p
L : Type v
inst✝² : CommSemiring L
inst✝¹ : CharP L p
inst✝ : PerfectRing L p
f : K →+* L
x✝ : PerfectClosure K p
n : ℕ
x : K
y✝ : PerfectClosure K p
m : ℕ
y : K
this : ∀ (n : ℕ), LeftInverse (⇑(frobeniusEquiv L p).symm)^[n] (⇑(frobenius L p))^[n]
⊢ (⇑(frobeniusEquiv L p).symm)^[n] (f x) + (⇑(frobeniusEquiv L p).symm)^[m] (f y) =
    (⇑(frobeniusEquiv L p).symm)^[n] (f x) + (⇑(frobeniusEquiv L p).symm)^[m] (f y)
Module: Mathlib.GroupTheory.CosetCover

Goal state before:
pp: G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq (Subgroup G)
n : ℕ
ih :
  ∀ m < n,
    ∀ {ι : Type u_2} {H : ι → Subgroup G} {g : ι → G} {s : Finset ι},
      ⋃ i ∈ s, g i • ↑(H i) = Set.univ →
        ∀ j ∈ s,
          ⋃ i ∈ {x ∈ s | H x = H j}, g i • ↑(H i) ≠ Set.univ →
            m = (Finset.image H s).card → ∃ i ∈ s, H i ≠ H j ∧ (H i).FiniteIndex
ι : Type u_2
H : ι → Subgroup G
g : ι → G
s : Finset ι
hcovers : ⋃ i ∈ s, g i • ↑(H i) = Set.univ
j : ι
hj : j ∈ s
hcovers' : ⋃ i ∈ {x ∈ s | H x = H j}, g i • ↑(H i) ≠ Set.univ
hn : n = (Finset.image H s).card
x : G
hx : ∀ (y : G), y • ↑(H j) ⊆ ⋃ i ∈ {x ∈ s | H x ≠ H j}, (y * x⁻¹ * g i) • ↑(H i)
κ : Type u_2 := ↥({x ∈ s | H x ≠ H j}) × Option ↥({x ∈ s | H x = H j})
f : κ → G :=
  fun x_1 ↦
    match x_1 with
    | (k₁, some k₂) => g ↑k₂ * x⁻¹ * g ↑k₁
    | (k₁, none) => g ↑k₁
K : κ → Subgroup G := fun k ↦ H ↑k.1
k : κ
⊢ K k ∈ (Finset.image H s).erase (H j)

Tactic:
have := Finset.mem_filter.mp k.1.property

Goal state after:
G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq (Subgroup G)
n : ℕ
ih :
  ∀ m < n,
    ∀ {ι : Type u_2} {H : ι → Subgroup G} {g : ι → G} {s : Finset ι},
      ⋃ i ∈ s, g i • ↑(H i) = Set.univ →
        ∀ j ∈ s,
          ⋃ i ∈ {x ∈ s | H x = H j}, g i • ↑(H i) ≠ Set.univ →
            m = (Finset.image H s).card → ∃ i ∈ s, H i ≠ H j ∧ (H i).FiniteIndex
ι : Type u_2
H : ι → Subgroup G
g : ι → G
s : Finset ι
hcovers : ⋃ i ∈ s, g i • ↑(H i) = Set.univ
j : ι
hj : j ∈ s
hcovers' : ⋃ i ∈ {x ∈ s | H x = H j}, g i • ↑(H i) ≠ Set.univ
hn : n = (Finset.image H s).card
x : G
hx : ∀ (y : G), y • ↑(H j) ⊆ ⋃ i ∈ {x ∈ s | H x ≠ H j}, (y * x⁻¹ * g i) • ↑(H i)
κ : Type u_2 := ↥({x ∈ s | H x ≠ H j}) × Option ↥({x ∈ s | H x = H j})
f : κ → G :=
  fun x_1 ↦
    match x_1 with
    | (k₁, some k₂) => g ↑k₂ * x⁻¹ * g ↑k₁
    | (k₁, none) => g ↑k₁
K : κ → Subgroup G := fun k ↦ H ↑k.1
k : κ
this : ↑k.1 ∈ s ∧ H ↑k.1 ≠ H j
⊢ K k ∈ (Finset.image H s).erase (H j)