mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Geometry.Manifold.Instances.Icc

Goal state before:
pp: E : Type u_1
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℝ E
H : Type u_2
inst✝² : TopologicalSpace H
I : ModelWithCorners ℝ E H
M : Type u_3
inst✝¹ : TopologicalSpace M
inst✝ : ChartedSpace H M
x y : ℝ
h : Fact (x < y)
n : WithTop ℕ∞
f : ↑(Icc x y) → M
w : ↑(Icc x y)
⊢ ContMDiffWithinAt 𝓘(ℝ, ℝ) I n (f ∘ projIcc x y ⋯) (Icc x y) ↑w ↔ ContMDiffAt (𝓡∂ 1) I n f w

Tactic:
by
  refine ⟨fun hf ↦ ?_,
    fun hf ↦ hf.comp_contMDiffWithinAt_of_eq (contMDiffOn_projIcc w w.2) (by simp)⟩
  have A := contMDiff_subtypeVal_Icc (x := x) (y := y) (n := n) w
  rw [← contMDiffWithinAt_univ] at A ⊢
  convert! hf.comp _ A (fun z hz ↦ z.2)
  ext z
  simp

Goal state after:
Module: Mathlib.Geometry.Manifold.Instances.Sphere

Goal state before:
pp: E : Type u_1
inst✝¹ : NormedAddCommGroup E
inst✝ : InnerProductSpace ℝ E
c : Circle → ℂ := Subtype.val
⊢ (Continuous fun z ↦ z.1 * z.2) ∧
    ∀ (x : ℂ × ℂ) (y : ℂ),
      ContDiffOn ℝ ω (↑(extChartAt 𝓘(ℝ, ℂ) y) ∘ (fun z ↦ z.1 * z.2) ∘ ↑(extChartAt (𝓘(ℝ, ℂ).prod 𝓘(ℝ, ℂ)) x).symm)
        ((extChartAt (𝓘(ℝ, ℂ).prod 𝓘(ℝ, ℂ)) x).target ∩
          ↑(extChartAt (𝓘(ℝ, ℂ).prod 𝓘(ℝ, ℂ)) x).symm ⁻¹' (fun z ↦ z.1 * z.2) ⁻¹' (extChartAt 𝓘(ℝ, ℂ) y).source)

Tactic:
exact ⟨continuous_mul, fun x y => contDiff_mul.contDiffOn⟩

Goal state after:
Module: Mathlib.Geometry.Manifold.IntegralCurve.ExistUnique

Goal state before:
pp: E : Type u_1
inst✝⁶ : NormedAddCommGroup E
inst✝⁵ : NormedSpace ℝ E
H : Type u_2
inst✝⁴ : TopologicalSpace H
I : ModelWithCorners ℝ E H
M : Type u_3
inst✝³ : TopologicalSpace M
inst✝² : ChartedSpace H M
inst✝¹ : IsManifold I 1 M
γ γ' : ℝ → M
v : (x : M) → TangentSpace I x
t₀ : ℝ
inst✝ : T2Space M
a b : ℝ
ht₀ : t₀ ∈ Ioo a b
hγt : ∀ t ∈ Ioo a b, I.IsInteriorPoint (γ t)
hv : ContMDiff I I.tangent 1 fun x ↦ ⟨x, v x⟩
hγ : IsMIntegralCurveOn γ v (Ioo a b)
hγ' : IsMIntegralCurveOn γ' v (Ioo a b)
h : γ t₀ = γ' t₀
s : Set ℝ := {t | γ t = γ' t} ∩ Ioo a b
hs : s = {t | γ t = γ' t} ∩ Ioo a b
val✝ : ℝ
ht : val✝ ∈ Ioo a b
⊢ ContinuousAt (fun y ↦ γ ↑y) ⟨val✝, ht⟩

Tactic:
apply ContinuousAt.comp _ continuousAt_subtype_val

Goal state after:
E : Type u_1
inst✝⁶ : NormedAddCommGroup E
inst✝⁵ : NormedSpace ℝ E
H : Type u_2
inst✝⁴ : TopologicalSpace H
I : ModelWithCorners ℝ E H
M : Type u_3
inst✝³ : TopologicalSpace M
inst✝² : ChartedSpace H M
inst✝¹ : IsManifold I 1 M
γ γ' : ℝ → M
v : (x : M) → TangentSpace I x
t₀ : ℝ
inst✝ : T2Space M
a b : ℝ
ht₀ : t₀ ∈ Ioo a b
hγt : ∀ t ∈ Ioo a b, I.IsInteriorPoint (γ t)
hv : ContMDiff I I.tangent 1 fun x ↦ ⟨x, v x⟩
hγ : IsMIntegralCurveOn γ v (Ioo a b)
hγ' : IsMIntegralCurveOn γ' v (Ioo a b)
h : γ t₀ = γ' t₀
s : Set ℝ := ⋯
hs : s = {t | γ t = γ' t} ∩ Ioo a b
val✝ : ℝ
ht : val✝ ∈ Ioo a b
⊢ ContinuousAt γ ↑⟨val✝, ht⟩
Module: Mathlib.Geometry.Manifold.IntegralCurve.ExistUnique

Goal state before:
pp: E : Type u_1
inst✝⁶ : NormedAddCommGroup E
inst✝⁵ : NormedSpace ℝ E
H : Type u_2
inst✝⁴ : TopologicalSpace H
I : ModelWithCorners ℝ E H
M : Type u_3
inst✝³ : TopologicalSpace M
inst✝² : ChartedSpace H M
inst✝¹ : IsManifold I 1 M
γ γ' : ℝ → M
v : (x : M) → TangentSpace I x
t₀ : ℝ
inst✝ : T2Space M
a b : ℝ
ht₀ : t₀ ∈ Ioo a b
hγt : ∀ t ∈ Ioo a b, I.IsInteriorPoint (γ t)
hv : ContMDiff I I.tangent 1 fun x ↦ ⟨x, v x⟩
hγ : IsMIntegralCurveOn γ v (Ioo a b)
hγ' : IsMIntegralCurveOn γ' v (Ioo a b)
h : γ t₀ = γ' t₀
s : Set ℝ := {t | γ t = γ' t} ∩ Ioo a b
hs : s = {t | γ t = γ' t} ∩ Ioo a b
val✝ : ℝ
ht : val✝ ∈ Ioo a b
⊢ ContinuousAt (fun y ↦ γ' ↑y) ⟨val✝, ht⟩

Tactic:
apply ContinuousAt.comp _ continuousAt_subtype_val

Goal state after:
E : Type u_1
inst✝⁶ : NormedAddCommGroup E
inst✝⁵ : NormedSpace ℝ E
H : Type u_2
inst✝⁴ : TopologicalSpace H
I : ModelWithCorners ℝ E H
M : Type u_3
inst✝³ : TopologicalSpace M
inst✝² : ChartedSpace H M
inst✝¹ : IsManifold I 1 M
γ γ' : ℝ → M
v : (x : M) → TangentSpace I x
t₀ : ℝ
inst✝ : T2Space M
a b : ℝ
ht₀ : t₀ ∈ Ioo a b
hγt : ∀ t ∈ Ioo a b, I.IsInteriorPoint (γ t)
hv : ContMDiff I I.tangent 1 fun x ↦ ⟨x, v x⟩
hγ : IsMIntegralCurveOn γ v (Ioo a b)
hγ' : IsMIntegralCurveOn γ' v (Ioo a b)
h : γ t₀ = γ' t₀
s : Set ℝ := ⋯
hs : s = {t | γ t = γ' t} ∩ Ioo a b
val✝ : ℝ
ht : val✝ ∈ Ioo a b
⊢ ContinuousAt γ' ↑⟨val✝, ht⟩
Module: Mathlib.Geometry.Manifold.VectorField.LieBracket

Goal state before:
pp: case hs
𝕜 : Type u_1
inst✝¹³ : NontriviallyNormedField 𝕜
H : Type u_2
inst✝¹² : TopologicalSpace H
E : Type u_3
inst✝¹¹ : NormedAddCommGroup E
inst✝¹⁰ : NormedSpace 𝕜 E
I : ModelWithCorners 𝕜 E H
M : Type u_4
inst✝⁹ : TopologicalSpace M
inst✝⁸ : ChartedSpace H M
H' : Type u_5
inst✝⁷ : TopologicalSpace H'
E' : Type u_6
inst✝⁶ : NormedAddCommGroup E'
inst✝⁵ : NormedSpace 𝕜 E'
I' : ModelWithCorners 𝕜 E' H'
M' : Type u_7
inst✝⁴ : TopologicalSpace M'
inst✝³ : ChartedSpace H' M'
inst✝² : IsManifold I (minSmoothness 𝕜 2) M
inst✝¹ : IsManifold I' (minSmoothness 𝕜 2) M'
inst✝ : CompleteSpace E
n : ℕ∞ω
f : M → M'
V W : (x : M') → TangentSpace I' x
x₀ : M
s u : Set M
t : Set M'
hV : MDiffAt[t] (T% V) (f x₀)
hW : MDiffAt[t] (T% W) (f x₀)
hs : UniqueMDiff[s]
hu : UniqueMDiff[u]
hf : ContMDiffWithinAt I I' n f u x₀
hx₀ : x₀ ∈ s
hn : minSmoothness 𝕜 2 ≤ n
hst : f ⁻¹' t ∈ 𝓝[s] x₀
h'x₀ : x₀ ∈ closure[inst✝⁹] (interior u)
hsu : s ⊆ u
B :
  ContDiffWithinAt 𝕜 n (↑(extChartAt I' (f x₀)) ∘ f ∘ ↑(extChartAt I x₀).symm)
    (↑(extChartAt I x₀).symm ⁻¹' u ∩ (extChartAt I x₀).target) (↑(extChartAt I x₀) x₀)
this✝ :
  ↑(extChartAt I x₀).symm ⁻¹' s ∩ (extChartAt I x₀).target =ᶠ[𝓝 (↑(extChartAt I x₀) x₀)]
    ↑(extChartAt I x₀).symm ⁻¹' s ∩ range ↑I
this :
  IsSymmSndFDerivWithinAt 𝕜 (↑(extChartAt I' (f x₀)) ∘ f ∘ ↑(extChartAt I x₀).symm)
    (↑(extChartAt I x₀).symm ⁻¹' u ∩ (extChartAt I x₀).target) (↑(extChartAt I x₀) x₀)
⊢ UniqueDiffOn 𝕜 ((extChartAt I x₀).target ∩ ↑(extChartAt I x₀).symm ⁻¹' s)

Tactic:
exact UniqueMDiffOn.uniqueDiffOn_target_inter hs x₀

Goal state after:
Module: Mathlib.Geometry.Manifold.Riemannian.Basic

Goal state before:
pp: E : Type u_1
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace ℝ E
H : Type u_2
inst✝⁶ : TopologicalSpace H
I : ModelWithCorners ℝ E H
M : Type u_3
inst✝⁵ : TopologicalSpace M
inst✝⁴ : ChartedSpace H M
inst✝³ : RiemannianBundle fun x ↦ TangentSpace I x
inst✝² : IsManifold I 1 M
inst✝¹ : IsContinuousRiemannianBundle E fun x ↦ TangentSpace I x
inst✝ : RegularSpace M
x : M
s : Set M
hs : s ∈ 𝓝 x
C : ℝ≥0
C_pos : C > 0
hC✝ : ∀ᶠ (y : M) in 𝓝 x, ‖mfderiv% ↑(extChartAt I x) y‖ₑ < ↑C
u : Set M
u_mem : u ∈ 𝓝 x
u_closed : IsClosed[inst✝⁵] u
us : u ⊆ s
hu : u ⊆ {y | ‖mfderiv% ↑(extChartAt I x) y‖ₑ < ↑C}
uc : u ⊆ (extChartAt I x).source
uc' : u ⊆ (chartAt H x).source
v : Set M
hv : v ⊆ u
v_mem : v ∈ 𝓝 x
v_open : IsOpen[inst✝⁵] v
r : ℝ≥0
hr : ball (↑(extChartAt I x) x) ↑r ⊆ ↑(extChartAt I x).symm ⁻¹' v
r_pos : 0 < r
y : M
hy : y ∈ {y | riemannianEDist I x y < ↑(r / C)}
γ : ℝ → M
hγx : γ 0 = x
hγy : γ 1 = y
γ_smooth : ContMDiff 𝓘(ℝ, ℝ) I 1 γ
hγ : pathELength I γ 0 1 < ↑(r / C)
A : Set ℝ := γ ⁻¹' u
zero_mem : 0 ∈ A
A_closed : IsClosed (A ∩ Icc 0 1)
t₁ : ℝ
ht₁0 : 0 ≤ t₁
ht₁1 : t₁ < 1
t₁_mem : Icc 0 t₁ ⊆ A
γ' : ℝ → E := ↑(extChartAt I x) ∘ γ
hC : ContMDiffOn 𝓘(ℝ, ℝ) 𝓘(ℝ, E) 1 γ' (Icc 0 t₁)
h't' : 0 < t₁
⊢ ∫⁻ (t' : ℝ) in Icc 0 t₁, ↑C * ‖(mfderiv[Icc 0 t₁] γ t') 1‖ₑ = ↑C * pathELength I γ 0 t₁

Tactic:
by
      rw [lintegral_const_mul' _ _ ENNReal.coe_ne_top,
          pathELength_eq_lintegral_mfderivWithin_Icc]

Goal state after:
Module: Mathlib.Geometry.Manifold.VectorBundle.CovariantDerivative.Basic

Goal state before:
pp: 𝕜 : Type u_1
inst✝¹⁴ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝¹³ : NormedAddCommGroup E
inst✝¹² : NormedSpace 𝕜 E
H : Type u_3
inst✝¹¹ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
M : Type u_4
inst✝¹⁰ : TopologicalSpace M
inst✝⁹ : ChartedSpace H M
F : Type u_5
inst✝⁸ : NormedAddCommGroup F
inst✝⁷ : NormedSpace 𝕜 F
V : M → Type u_6
inst✝⁶ : TopologicalSpace (TotalSpace F V)
inst✝⁵ : (x : M) → AddCommGroup (V x)
inst✝⁴ : (x : M) → Module 𝕜 (V x)
inst✝³ : (x : M) → TopologicalSpace (V x)
inst✝² : ∀ (x : M), IsTopologicalAddGroup (V x)
inst✝¹ : ∀ (x : M), ContinuousSMul 𝕜 (V x)
inst✝ : FiberBundle F V
s : Set M
cov : ((x : M) → V x) → (x : M) → TangentSpace I x →L[𝕜] V x
hcov : IsCovariantDerivativeOn F cov s
cov' : ((x : M) → V x) → (x : M) → TangentSpace I x →L[𝕜] V x
hcov' : IsCovariantDerivativeOn F cov' s
g : M → 𝕜
σ✝ : (x : M) → V x
g✝ : M → 𝕜
x✝ : M
hσ : MDiffAt (T% σ✝) x✝
hφ : MDiffAt g✝ x✝
hx : x✝ ∈ s
⊢ (g • cov (g✝ • σ✝) + (1 - g) • cov' (g✝ • σ✝)) x✝ =
    g✝ x✝ • (g • cov σ✝ + (1 - g) • cov' σ✝) x✝ + (d% g✝ x✝).smulRight (σ✝ x✝)

Tactic:
by
    simp [hcov.leibniz hσ hφ, hcov'.leibniz hσ hφ]
    module

Goal state after:
Module: Mathlib.GroupTheory.SpecificGroups.Dihedral

Goal state before:
pp: case succ
n : ℕ
i : ZMod n
k : ℕ
IH : r i ^ k = r (i * ↑k)
⊢ i * ↑k + i = i * (↑k + 1)

Tactic:
mul_add,

Goal state after:
case succ
n : ℕ
i : ZMod n
k : ℕ
IH : r i ^ k = r (i * ↑k)
⊢ i * ↑k + i = i * ↑k + i * 1
Module: Mathlib.GroupTheory.PresentedGroup

Goal state before:
pp: case mk.mul
α : Type u_1
rels : Set (FreeGroup α)
H : Subgroup (PresentedGroup rels)
h : ∀ (j : α), of j ∈ H
x : PresentedGroup rels
x✝ y✝ : FreeGroup α
h1 : Quot.mk (⇑(QuotientGroup.leftRel (Subgroup.normalClosure rels))) x✝ ∈ H
h2 : Quot.mk (⇑(QuotientGroup.leftRel (Subgroup.normalClosure rels))) y✝ ∈ H
⊢ ↑(x✝ * y✝) ∈ H.carrier

Tactic:
QuotientGroup.mk_mul

Goal state after:
case mk.mul
α : Type u_1
rels : Set (FreeGroup α)
H : Subgroup (PresentedGroup rels)
h : ∀ (j : α), of j ∈ H
x : PresentedGroup rels
x✝ y✝ : FreeGroup α
h1 : Quot.mk (⇑(QuotientGroup.leftRel (Subgroup.normalClosure rels))) x✝ ∈ H
h2 : Quot.mk (⇑(QuotientGroup.leftRel (Subgroup.normalClosure rels))) y✝ ∈ H
⊢ ↑x✝ * ↑y✝ ∈ H.carrier
Module: Mathlib.GroupTheory.CoprodI

Goal state before:
pp: ι : Type u_1
M : ι → Type u_2
inst✝² : (i : ι) → Monoid (M i)
N : Type u_3
inst✝¹ : Monoid N
G : ι → Type u_4
inst✝ : (i : ι) → Group (G i)
m : CoprodI G
⊢ MulOpposite.unop ((lift fun i ↦ (MonoidHom.op of).comp (MulEquiv.inv' (G i)).toMonoidHom) m) * m = 1

Tactic:
induction m using CoprodI.induction_on with

Goal state after:
Module: Mathlib.GroupTheory.CoprodI

Goal state before:
pp: case neg
ι : Type u_1
M : ι → Type u_2
inst✝¹ : (i : ι) → Monoid (M i)
inst✝ : (i : ι) → DecidableEq (M i)
i : ι
m : M i
w : Word M
m' : M i
w' : Word M
h' : w'.fstIdx ≠ some i
hm : m = 1
hm' : ¬m' = 1
h : (cons m' w' ⋯ ⋯).fstIdx ≠ some i
he : w = cons m' w' ⋯ ⋯
⊢ False

Tactic:
exact h rfl

Goal state after:
Module: Mathlib.GroupTheory.CoprodI

Goal state before:
pp: case inr
ι : Type u_1
M : ι → Type u_2
inst✝² : (i : ι) → Monoid (M i)
inst✝¹ : DecidableEq ι
inst✝ : (i : ι) → DecidableEq (M i)
i j : ι
w : Word M
m : M i
⊢ (i ≠ j ∧ ∃ (h : w.toList ≠ []), w.toList.head h = ⟨i, m⟩) → ⟨i, m⟩ ∈ w.toList

Tactic:
cases w.toList <;> simp +contextual

Goal state after:
Module: Mathlib.GroupTheory.Coxeter.Matrix

Goal state before:
pp: B : Type u_1
B' : Type u_2
e : B ≃ B'
M : CoxeterMatrix B
n : ℕ
⊢ (Matrix.of fun i j ↦ if i = j then 1 else if ↑j + 1 = ↑i ∨ ↑i + 1 = ↑j then 3 else 2).IsSymm

Tactic:
unfold Matrix.IsSymm; aesop

Goal state after:
Module: Mathlib.GroupTheory.Coxeter.Matrix

Goal state before:
pp: B : Type u_1
B' : Type u_2
e : B ≃ B'
M : CoxeterMatrix B
n : ℕ
⊢ (Matrix.of fun i j ↦
      if i = j then 1
      else
        if ↑i = n - 1 ∧ ↑j = n - 2 ∨ ↑j = n - 1 ∧ ↑i = n - 2 then 4
        else if ↑j + 1 = ↑i ∨ ↑i + 1 = ↑j then 3 else 2).IsSymm

Tactic:
unfold Matrix.IsSymm; aesop

Goal state after:
Module: Mathlib.GroupTheory.Coxeter.Matrix

Goal state before:
pp: B : Type u_1
B' : Type u_2
e : B ≃ B'
M : CoxeterMatrix B
n : ℕ
⊢ (Matrix.of fun i j ↦
      if i = j then 1
      else
        if ↑i = n - 1 ∧ ↑j = n - 3 ∨ ↑j = n - 1 ∧ ↑i = n - 3 then 3
        else if ↑j + 1 = ↑i ∨ ↑i + 1 = ↑j then 3 else 2).IsSymm

Tactic:
unfold Matrix.IsSymm; aesop

Goal state after:
Module: Mathlib.GroupTheory.Coxeter.Matrix

Goal state before:
pp: B : Type u_1
B' : Type u_2
e : B ≃ B'
M : CoxeterMatrix B
n m : ℕ
⊢ (Matrix.of fun i j ↦ if i = j then 1 else m + 2).IsSymm

Tactic:
unfold Matrix.IsSymm; aesop

Goal state after:
Module: Mathlib.GroupTheory.Coxeter.Length

Goal state before:
pp: case h₁
B : Type u_1
W : Type u_2
inst✝ : Group W
M : CoxeterMatrix B
cs : CoxeterSystem M W
ω : List B
hω : cs.IsReduced ω
this : cs.length (cs.wordProd ω.reverse) ≤ ω.reverse.length
⊢ cs.length (cs.wordProd ω)⁻¹ ≤ cs.length (cs.wordProd ω)

Tactic:
rwa [wordProd_reverse, length_reverse, ← hω] at this

Goal state after:
Module: Mathlib.GroupTheory.Coxeter.Length

Goal state before:
pp: B : Type u_1
W : Type u_2
inst✝ : Group W
M : CoxeterMatrix B
cs : CoxeterSystem M W
ω : List B
hω : cs.IsReduced ω
⊢ cs.lengthParity (cs.wordProd ω) = Multiplicative.ofAdd ↑ω.length

Tactic:
wordProd,

Goal state after:
B : Type u_1
W : Type u_2
inst✝ : Group W
M : CoxeterMatrix B
cs : CoxeterSystem M W
ω : List B
hω : cs.IsReduced ω
⊢ cs.lengthParity (List.map cs.simple ω).prod = Multiplicative.ofAdd ↑ω.length
Module: Mathlib.GroupTheory.CoprodI

Goal state before:
pp: ι : Type u_1
M : ι → Type u_2
inst✝² : (i : ι) → Monoid (M i)
inst✝¹ : DecidableEq ι
inst✝ : (i : ι) → DecidableEq (M i)
m : CoprodI M
⊢ ∀ (w : Word M), (m • w).prod = m * w.prod

Tactic:
induction m using CoprodI.induction_on with

Goal state after:
Module: Mathlib.GroupTheory.CoprodI

Goal state before:
pp: ι : Type u_1
G : Type u_4
inst✝² : Group G
H : ι → Type u_5
inst✝¹ : (i : ι) → Group (H i)
f : (i : ι) → H i →* G
α : Type u_6
inst✝ : MulAction G α
X : ι → Set α
hpp : Pairwise fun i j ↦ ∀ (h : H i), h ≠ 1 → (f i) h • X j ⊆ X i
i✝ j✝ i j k✝ l : ι
w₁ : NeWord H i j
hne : j ≠ k✝
w₂ : NeWord H k✝ l
hIw₁ : ∀ {k : ι}, j ≠ k → (lift f) w₁.prod • X k ⊆ X i
hIw₂ : ∀ {k : ι}, l ≠ k → (lift f) w₂.prod • X k ⊆ X k✝
k : ι
hk : l ≠ k
⊢ (lift f) (w₁.append hne w₂).prod • X k = (lift f) w₁.prod • (lift f) w₂.prod • X k

Tactic:
simp [mul_smul]

Goal state after:
Module: Mathlib.GroupTheory.CoprodI

Goal state before:
pp: ι✝ : Type u_1
M : ι✝ → Type u_2
inst✝² : (i : ι✝) → Monoid (M i)
N : Type u_3
inst✝¹ : Monoid N
ι : Type u_4
X : ι → Type u_5
G : ι → Type u_6
inst✝ : (i : ι) → Group (G i)
B : (i : ι) → FreeGroupBasis (X i) (G i)
i : ι
⊢ ((FreeGroup.lift fun x ↦ of ((B x.fst) x.snd)).comp (lift fun i ↦ (B i).lift fun x ↦ FreeGroup.of ⟨i, x⟩)).comp of =
    (MonoidHom.id (CoprodI G)).comp of

Tactic:
apply (B i).ext_hom

Goal state after:
ι✝ : Type u_1
M : ι✝ → Type u_2
inst✝² : (i : ι✝) → Monoid (M i)
N : Type u_3
inst✝¹ : Monoid N
ι : Type u_4
X : ι → Type u_5
G : ι → Type u_6
inst✝ : (i : ι) → Group (G i)
B : (i : ι) → FreeGroupBasis (X i) (G i)
i : ι
⊢ ∀ (i_1 : X i),
    (((FreeGroup.lift fun x ↦ of ((B x.fst) x.snd)).comp (lift fun i ↦ (B i).lift fun x ↦ FreeGroup.of ⟨i, x⟩)).comp of)
        ((B i) i_1) =
      ((MonoidHom.id (CoprodI G)).comp of) ((B i) i_1)
Module: Mathlib.GroupTheory.CoprodI

Goal state before:
pp: case hXnonempty
ι : Type u_1
inst✝² : Nontrivial ι
G : Type u_1
inst✝¹ : Group G
a : ι → G
α : Type u_4
inst✝ : MulAction G α
X Y : ι → Set α
hXnonempty : ∀ (i : ι), (X i).Nonempty
hXdisj : Pairwise (Disjoint on X)
hYdisj : Pairwise (Disjoint on Y)
hXYdisj : ∀ (i j : ι), Disjoint (X i) (Y j)
hX : ∀ (i : ι), a i • (Y i)ᶜ ⊆ X i
hY : ∀ (i : ι), a⁻¹ i • (X i)ᶜ ⊆ Y i
H : ι → Type := ⋯
f : (i : ι) → H i →* G := ⋯
X' : ι → Set α := ⋯
⊢ ∀ (i : ι), (X' i).Nonempty

Tactic:
show ∀ i, (X' i).Nonempty

Goal state after:
case hXnonempty
ι : Type u_1
inst✝² : Nontrivial ι
G : Type u_1
inst✝¹ : Group G
a : ι → G
α : Type u_4
inst✝ : MulAction G α
X Y : ι → Set α
hXnonempty : ∀ (i : ι), (X i).Nonempty
hXdisj : Pairwise (Disjoint on X)
hYdisj : Pairwise (Disjoint on Y)
hXYdisj : ∀ (i j : ι), Disjoint (X i) (Y j)
hX : ∀ (i : ι), a i • (Y i)ᶜ ⊆ X i
hY : ∀ (i : ι), a⁻¹ i • (X i)ᶜ ⊆ Y i
H : ι → Type := ⋯
f : (i : ι) → H i →* G := ⋯
X' : ι → Set α := ⋯
⊢ ∀ (i : ι), (X' i).Nonempty
Module: Mathlib.GroupTheory.Frattini

Goal state before:
pp: G : Type u_1
H : Type u_2
inst✝¹ : Group G
inst✝ : Group H
φ : G →* H
hφ : Function.Surjective ⇑φ
⊢ frattini G ≤ comap φ (frattini H)

Tactic:
simp_rw [frattini, Order.radical, comap_iInf, le_iInf_iff]

Goal state after:
G : Type u_1
H : Type u_2
inst✝¹ : Group G
inst✝ : Group H
φ : G →* H
hφ : Function.Surjective ⇑φ
⊢ ∀ i ∈ {H_1 | IsCoatom H_1}, ⨅ a ∈ {H | IsCoatom H}, a ≤ comap φ i
Module: Mathlib.GroupTheory.Nilpotent

Goal state before:
pp: G : Type u_1
inst✝¹ : Group G
N : Subgroup G
inst✝ : N.Normal
⊢ N.upperCentralSeriesStep = comap (mk' N) (center (G ⧸ N))

Tactic:
ext
  rw [mem_comap, mem_center_iff, forall_mk]
  refine forall_congr' fun y => ?_
  rw [coe_mk', ← QuotientGroup.mk_mul, ← QuotientGroup.mk_mul, eq_comm, eq_iff_div_mem,
    div_eq_mul_inv, mul_inv_rev, commutatorElement_def]
  simp_rw [mul_assoc]

Goal state after:
Module: Mathlib.GroupTheory.Nilpotent

Goal state before:
pp: G : Type u_1
inst✝ : Group G
H : ℕ → Subgroup G
n : ℕ
hn : H n = ⊥
h0 : H 0 = ⊤
hH : ∀ (x : G) (n : ℕ), x ∈ H n → ∀ (g : G), ⁅x, g⁆ ∈ H (n + 1)
x : G
m : ℕ
hx : x ∈ (fun m ↦ H (n - m)) (m + 1)
g : G
⊢ ⁅x, g⁆ ∈ (fun m ↦ H (n - m)) m

Tactic:
dsimp only at hx ⊢

Goal state after:
G : Type u_1
inst✝ : Group G
H : ℕ → Subgroup G
n : ℕ
hn : H n = ⊥
h0 : H 0 = ⊤
hH : ∀ (x : G) (n : ℕ), x ∈ H n → ∀ (g : G), ⁅x, g⁆ ∈ H (n + 1)
x : G
m : ℕ
hx : x ∈ H (n - (m + 1))
g : G
⊢ ⁅x, g⁆ ∈ H (n - m)
Module: Mathlib.GroupTheory.FreeGroup.Orbit

Goal state before:
pp: α : Type u_1
inst✝ : DecidableEq α
a b : α × Bool
h : ∀ (x : FreeGroup α), x.toWord[0]? = some a ↔ x.toWord[0]? = some b
⊢ a = b

Tactic:
simpa using h (mk [a])

Goal state after:
Module: Mathlib.GroupTheory.FreeGroup.NielsenSchreier

Goal state before:
pp: case pos
G : Type u
inst✝³ : Groupoid G
inst✝² : IsFreeGroupoid G
T : WideSubquiver (Symmetrify (Generators G))
inst✝¹ : Arborescence (WideSubquiver.toType (Symmetrify (Generators G)) T)
X : Type u
inst✝ : Group X
f : ↑(wideSubquiverEquivSetTotal (wideSubquiverSymmetrify T))ᶜ → X
f' : Labelling (Generators G) X :=
  fun a b e ↦ if h : e ∈ wideSubquiverSymmetrify T a b then 1 else f ⟨{ left := a, right := b, hom := e }, h⟩
F' : G ⥤ CategoryTheory.SingleObj X
hF' : ∀ (a b : Generators G) (g : a ⟶ b), F'.map (of g) = f' g
uF' :
  ∀ (y : G ⥤ CategoryTheory.SingleObj X), (fun F ↦ ∀ (a b : Generators G) (g : a ⟶ b), F.map (of g) = f' g) y → y = F'
E : End (root' T) →* X
hE : ∀ (a : ↑(wideSubquiverEquivSetTotal (wideSubquiverSymmetrify T))ᶜ), E (loopOfHom T (of (↑a).hom)) = f a
x : End (root' T)
a b : Generators G
e : a ⟶ b
h : e ∈ wideSubquiverSymmetrify T a b
⊢ E (loopOfHom T (of e)) = 1

Tactic:
rw [loopOfHom_eq_id T e h, ← End.one_def, E.map_one]

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

Goal state before:
pp: G : Type u_1
inst✝² : Group G
X : Type u_2
inst✝¹ : MulAction G X
N : Subgroup G
inst✝ : N.Normal
a : X
g : G
⊢ g • orbit (↥N) a = orbit (↥N) a ∨ Disjoint (g • orbit (↥N) a) (orbit (↥N) a)

Tactic:
smul_orbit_eq_orbit_smul

Goal state after:
G : Type u_1
inst✝² : Group G
X : Type u_2
inst✝¹ : MulAction G X
N : Subgroup G
inst✝ : N.Normal
a : X
g : G
⊢ orbit (↥N) (g • a) = orbit (↥N) a ∨ Disjoint (orbit (↥N) (g • a)) (orbit (↥N) a)
Module: Mathlib.GroupTheory.GroupAction.Blocks

Goal state before:
pp: G : Type u_1
inst✝⁵ : Group G
S : Type u_3
H : Type u_4
inst✝⁴ : Group H
inst✝³ : SetLike S H
inst✝² : SubgroupClass S H
s : S
inst✝¹ : MulAction G H
inst✝ : IsScalarTower G H H
a b : G
hab : a • ↑s ≠ b • ↑s
c : H
hc : c ∈ ↑s
d : H
hd : d ∈ ↑s
hcd : b • d = a • c
⊢ (b • d) • ↑s = b • c • ↑s

Tactic:
smul_assoc,

Goal state after:
G : Type u_1
inst✝⁵ : Group G
S : Type u_3
H : Type u_4
inst✝⁴ : Group H
inst✝³ : SetLike S H
inst✝² : SubgroupClass S H
s : S
inst✝¹ : MulAction G H
inst✝ : IsScalarTower G H H
a b : G
hab : a • ↑s ≠ b • ↑s
c : H
hc : c ∈ ↑s
d : H
hd : d ∈ ↑s
hcd : b • d = a • c
⊢ b • d • ↑s = b • c • ↑s
Module: Mathlib.GroupTheory.GroupAction.Blocks

Goal state before:
pp: G : Type u_1
inst✝⁵ : Group G
S : Type u_3
H : Type u_4
inst✝⁴ : Group H
inst✝³ : SetLike S H
inst✝² : SubgroupClass S H
s : S
inst✝¹ : MulAction G H
inst✝ : IsScalarTower G Hᵐᵒᵖ H
a b : G
hab : a • ↑s ≠ b • ↑s
c : H
hc : c ∈ ↑s
d : H
hd : d ∈ ↑s
hcd : b • d = a • c
⊢ (b • op d) • ↑s = b • op c • ↑s

Tactic:
smul_assoc,

Goal state after:
G : Type u_1
inst✝⁵ : Group G
S : Type u_3
H : Type u_4
inst✝⁴ : Group H
inst✝³ : SetLike S H
inst✝² : SubgroupClass S H
s : S
inst✝¹ : MulAction G H
inst✝ : IsScalarTower G Hᵐᵒᵖ H
a b : G
hab : a • ↑s ≠ b • ↑s
c : H
hc : c ∈ ↑s
d : H
hd : d ∈ ↑s
hcd : b • d = a • c
⊢ b • op d • ↑s = b • op c • ↑s
Module: Mathlib.GroupTheory.GroupAction.Blocks

Goal state before:
pp: case inr.«0»
G : Type u_1
inst✝² : Group G
X : Type u_2
inst✝¹ : MulAction G X
inst✝ : IsPretransitive G X
B : Set X
hX : Finite X
hB : IsBlock G B
hB_ne : B.Nonempty
hB' : 0 < 2
key : B.ncard * 0 = Nat.card X
⊢ B = Set.univ

Tactic:
mul_zero,

Goal state after:
case inr.«0»
G : Type u_1
inst✝² : Group G
X : Type u_2
inst✝¹ : MulAction G X
inst✝ : IsPretransitive G X
B : Set X
hX : Finite X
hB : IsBlock G B
hB_ne : B.Nonempty
hB' : 0 < 2
key : 0 = Nat.card X
⊢ B = Set.univ
Module: Mathlib.GroupTheory.GroupAction.Primitive

Goal state before:
pp: G : Type u_1
X : Type u_2
inst✝¹ : Group G
inst✝ : MulAction G X
a : X
ha : a ∉ fixedPoints G X
H : ∀ ⦃B : Set X⦄, a ∈ B → IsBlock G B → IsTrivialBlock B
this : IsPretransitive G X
B : Set X
hB : IsBlock G B
⊢ IsTrivialBlock B

Tactic:
by
      obtain rfl | ⟨b, hb⟩ := B.eq_empty_or_nonempty
      · simp [IsTrivialBlock]
      · obtain ⟨g, hg⟩ := exists_smul_eq G b a
        rw [← IsTrivialBlock.smul_iff g]
        exact H ⟨b, hb, hg⟩ (hB.translate g)

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

Goal state before:
pp: G : Type u_1
X : Type u_2
inst✝⁶ : Group G
inst✝⁵ : MulAction G X
H : Type u_3
Y : Type u_4
inst✝⁴ : Group H
inst✝³ : MulAction H Y
φ : G → H
f : X →ₑ[φ] Y
inst✝² : Finite Y
inst✝¹ : IsPretransitive H Y
inst✝ : IsPreprimitive G X
hf' : Nat.card Y < 2 * (Set.range ⇑f).ncard
B : Set Y
hB : IsBlock H B
hB' : B.Nonempty
hB_ne_top : ¬B = Set.univ
hfin : Fintype ↑(Set.range fun g ↦ g • B)
g : H
h : ⇑f ⁻¹' (g • B) = Set.univ
⊢ False

Tactic:
simp only [Set.preimage_eq_univ_iff] at h

Goal state after:
G : Type u_1
X : Type u_2
inst✝⁶ : Group G
inst✝⁵ : MulAction G X
H : Type u_3
Y : Type u_4
inst✝⁴ : Group H
inst✝³ : MulAction H Y
φ : G → H
f : X →ₑ[φ] Y
inst✝² : Finite Y
inst✝¹ : IsPretransitive H Y
inst✝ : IsPreprimitive G X
hf' : Nat.card Y < 2 * (Set.range ⇑f).ncard
B : Set Y
hB : IsBlock H B
hB' : B.Nonempty
hB_ne_top : ¬B = Set.univ
hfin : Fintype ↑(Set.range fun g ↦ g • B)
g : H
h : Set.range ⇑f ⊆ g • B
⊢ False
Module: Mathlib.GroupTheory.SpecificGroups.Alternating

Goal state before:
pp: case succ
α : Type u_1
inst✝¹ : Fintype α
inst✝ : DecidableEq α
σ : Perm α
hσ : σ ∈ alternatingGroup α
n : ℕ
ih : ∀ (l : List (Perm α)), (∀ g ∈ l, g.IsSwap) → l.length = 2 * n → l.prod ∈ closure {σ | σ.IsThreeCycle}
a : Perm α
l : List (Perm α)
hl : ∀ g ∈ a :: l, g.IsSwap
hn : l.length = 2 * n + 1
⊢ (a :: l).prod ∈ closure {σ | σ.IsThreeCycle}

Tactic:
obtain ⟨b, l, rfl⟩ := l.exists_of_length_succ hn

Goal state after:
case succ
α : Type u_1
inst✝¹ : Fintype α
inst✝ : DecidableEq α
σ : Perm α
hσ : σ ∈ alternatingGroup α
n : ℕ
ih : ∀ (l : List (Perm α)), (∀ g ∈ l, g.IsSwap) → l.length = 2 * n → l.prod ∈ closure {σ | σ.IsThreeCycle}
a b : Perm α
l : List (Perm α)
hl : ∀ g ∈ a :: b :: l, g.IsSwap
hn : (b :: l).length = 2 * n + 1
⊢ (a :: b :: l).prod ∈ closure {σ | σ.IsThreeCycle}