mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.MeasureTheory.Function.ConditionalLExpectation

Goal state before:
pp: case pos
Ω : Type u_1
mΩ₀ : MeasurableSpace Ω
P : Measure Ω
ι : Type u_2
mΩ : MeasurableSpace Ω
inst✝ : Countable ι
X : ι → Ω → ℝ≥0∞
hX : ∀ (i : ι), AEMeasurable (X i) P
hm : mΩ ≤ mΩ₀
hσ : SigmaFinite (P.trim hm)
s : Set Ω
hs : MeasurableSet s
⊢ ∑' (i : ι), ∫⁻ (a : Ω) in s, P⁻[X i | mΩ] a ∂P = ∑' (i : ι), ∫⁻ (a : Ω) in s, X i a ∂P

Tactic:
rw [lintegral_tsum (by measurability)]

Goal state after:
case pos
Ω : Type u_1
mΩ₀ : MeasurableSpace Ω
P : Measure Ω
ι : Type u_2
mΩ : MeasurableSpace Ω
inst✝ : Countable ι
X : ι → Ω → ℝ≥0∞
hX : ∀ (i : ι), AEMeasurable (X i) P
hm : mΩ ≤ mΩ₀
hσ : SigmaFinite (P.trim hm)
s : Set Ω
hs : MeasurableSet s
⊢ ∑' (i : ι), ∫⁻ (a : Ω) in s, P⁻[X i | mΩ] a ∂P = ∑' (i : ι), ∫⁻ (a : Ω) in s, X i a ∂P
Module: Mathlib.LinearAlgebra.AffineSpace.Matrix

Goal state before:
pp: ι : Type u₁
k : Type u₂
V : Type u₃
P : Type u₄
inst✝⁴ : AddCommGroup V
inst✝³ : AffineSpace V P
inst✝² : Ring k
inst✝¹ : Module k V
b : AffineBasis ι k P
inst✝ : Fintype ι
b₂ : AffineBasis ι k P
x : P
⊢ b₂.coords x ᵥ* b.toMatrix ⇑b₂ = b.coords x

Tactic:
by
  ext j
  change _ = b.coord j x
  conv_rhs => rw [← b₂.affineCombination_coord_eq_self x]
  rw [Finset.map_affineCombination _ _ _ (b₂.sum_coord_apply_eq_one x)]
  simp [Matrix.vecMul, dotProduct, toMatrix_apply, coords]

Goal state after:
Module: Mathlib.RingTheory.TensorProduct.IsBaseChangeHom

Goal state before:
pp: R : Type u_1
inst✝¹² : CommSemiring R
S : Type u_2
inst✝¹¹ : CommSemiring S
inst✝¹⁰ : Algebra R S
M : Type u_3
inst✝⁹ : AddCommMonoid M
inst✝⁸ : Module R M
N : Type u_4
inst✝⁷ : AddCommMonoid N
inst✝⁶ : Module R N
P : Type u_5
inst✝⁵ : AddCommMonoid P
inst✝⁴ : Module R P
inst✝³ : Module S P
inst✝² : IsScalarTower R S P
inst✝¹ : Free R M
inst✝ : Module.Finite R M
ε : N →ₗ[R] P
ibc : IsBaseChange S ε
ι : Type u_3 := Free.ChooseBasisIndex R M
b : Basis ι R M
this✝ : Fintype (Free.ChooseBasisIndex R M)
e : (M →ₗ[R] N) ≃ₗ[R] ι → N := LinearEquiv.congrLeft N R b.repr ≪≫ₗ (Finsupp.llift N R R ι).symm
f : (M →ₗ[R] P) ≃ₗ[S] ι → P := LinearEquiv.congrLeft P S b.repr ≪≫ₗ (Finsupp.llift P R S ι).symm
h : S ⊗[R] (M →ₗ[R] N) →ₗ[S] M →ₗ[R] P := linearMapRightBaseChangeHom S M ε
e' : S ⊗[R] (M →ₗ[R] N) ≃ₗ[S] S ⊗[R] (ι → N) := LinearEquiv.baseChange R S (M →ₗ[R] N) (ι → N) e
h' : S ⊗[R] (ι → N) →ₗ[S] ι → P := (↑f ∘ₗ linearMapRightBaseChangeHom S M ε) ∘ₗ ↑e'.symm
this : ↑f ∘ₗ linearMapRightBaseChangeHom S M ε = ↑⋯.equiv ∘ₗ ↑e'
⊢ h' = ↑⋯.equiv

Tactic:
by
    simp [h', this, ← LinearEquiv.trans_assoc e'.symm e']

Goal state after:
Module: Mathlib.RingTheory.TensorProduct.IsBaseChangeHom

Goal state before:
pp: R : Type u_1
inst✝¹⁰ : CommSemiring R
S : Type u_2
inst✝⁹ : CommSemiring S
inst✝⁸ : Algebra R S
M : Type u_3
inst✝⁷ : AddCommMonoid M
inst✝⁶ : Module R M
P : Type u_5
inst✝⁵ : AddCommMonoid P
inst✝⁴ : Module R P
inst✝³ : Module S P
inst✝² : IsScalarTower R S P
inst✝¹ : Free R M
inst✝ : Module.Finite R M
α : M →ₗ[R] P
j : IsBaseChange S α
f : M →ₗ[R] M
p : P
⊢ ((⋯.equiv ≪≫ₗ liftBaseChangeEquiv S ≪≫ₗ LinearEquiv.congrLeft P S j.equiv) (1 ⊗ₜ[R] f)) p = (j.endHom f) p

Tactic:
simp [equiv_tmul, LinearEquiv.congrLeft, endHom_apply]

Goal state after:
Module: Mathlib.LinearAlgebra.Alternating.DomCoprod

Goal state before:
pp: ιa : Type u_1
ιb : Type u_2
inst✝¹⁰ : Fintype ιa
inst✝⁹ : Fintype ιb
R' : Type u_3
Mᵢ : Type u_4
N₁ : Type u_5
N₂ : Type u_6
inst✝⁸ : CommSemiring R'
inst✝⁷ : AddCommGroup N₁
inst✝⁶ : Module R' N₁
inst✝⁵ : AddCommGroup N₂
inst✝⁴ : Module R' N₂
inst✝³ : AddCommMonoid Mᵢ
inst✝² : Module R' Mᵢ
inst✝¹ : DecidableEq ιa
inst✝ : DecidableEq ιb
a : MultilinearMap R' (fun x ↦ Mᵢ) N₁
b : MultilinearMap R' (fun x ↦ Mᵢ) N₂
σ : Perm (ιa ⊕ ιb)
f : Perm ιa × Perm ιb →* Perm (ιa ⊕ ιb) := sumCongrHom ιa ιb
⊢ ∑ x with ∃ x_1, (sumCongrHom ιa ιb) x_1 = x, sign (σ * x) • domDomCongr (σ * x) (a.domCoprod b) =
    ∑ x, sign (σ * (sumCongrHom ιa ιb) x) • domDomCongr (σ * (sumCongrHom ιa ιb) x) (a.domCoprod b)

Tactic:
Finset.univ_filter_exists,

Goal state after:
ιa : Type u_1
ιb : Type u_2
inst✝¹⁰ : Fintype ιa
inst✝⁹ : Fintype ιb
R' : Type u_3
Mᵢ : Type u_4
N₁ : Type u_5
N₂ : Type u_6
inst✝⁸ : CommSemiring R'
inst✝⁷ : AddCommGroup N₁
inst✝⁶ : Module R' N₁
inst✝⁵ : AddCommGroup N₂
inst✝⁴ : Module R' N₂
inst✝³ : AddCommMonoid Mᵢ
inst✝² : Module R' Mᵢ
inst✝¹ : DecidableEq ιa
inst✝ : DecidableEq ιb
a : MultilinearMap R' (fun x ↦ Mᵢ) N₁
b : MultilinearMap R' (fun x ↦ Mᵢ) N₂
σ : Perm (ιa ⊕ ιb)
f : Perm ιa × Perm ιb →* Perm (ιa ⊕ ιb) := sumCongrHom ιa ιb
⊢ ∑ x ∈ Finset.image (⇑(sumCongrHom ιa ιb)) Finset.univ, sign (σ * x) • domDomCongr (σ * x) (a.domCoprod b) =
    ∑ x, sign (σ * (sumCongrHom ιa ιb) x) • domDomCongr (σ * (sumCongrHom ιa ιb) x) (a.domCoprod b)
Module: Mathlib.LinearAlgebra.Transvection.Basic

Goal state before:
pp: R : Type u_1
V : Type u_2
inst✝² : Semiring R
inst✝¹ : AddCommMonoid V
inst✝ : Module R V
f : Dual R V
v : V
r s : R
⊢ transvection f (r • v) ∘ₗ transvection f (s • v) = transvection f ((r + s + s * f v * r) • v)

Tactic:
ext x
  simp only [LinearMap.comp_apply, apply, map_add, map_smul, add_assoc]
  simp only [smul_add, ← mul_smul, ← add_smul, ← mul_add (f x), mul_assoc]

Goal state after:
Module: Mathlib.LinearAlgebra.Transvection.Basic

Goal state before:
pp: R : Type u_3
V : Type u_4
inst✝⁵ : CommSemiring R
inst✝⁴ : AddCommMonoid V
inst✝³ : Module R V
inst✝² : Free R V
inst✝¹ : Module.Finite R V
inst✝ : StrongRankCondition R
f : Dual R V
v : V
h : finrank R V = 1
h1 : 1 ≤ 1
b : Basis (Fin (finrank R V)) R V := finBasis R V
x : V
i : Fin (finrank R V) := ⟨0, ⋯⟩
hfv : f (b i) * (b.repr v) i = 0
this : ∀ (x : V), x = (b.repr x) i • b i
⊢ f x • v = 0

Tactic:
this x,

Goal state after:
R : Type u_3
V : Type u_4
inst✝⁵ : CommSemiring R
inst✝⁴ : AddCommMonoid V
inst✝³ : Module R V
inst✝² : Free R V
inst✝¹ : Module.Finite R V
inst✝ : StrongRankCondition R
f : Dual R V
v : V
h : finrank R V = 1
h1 : 1 ≤ 1
b : Basis (Fin (finrank R V)) R V := finBasis R V
x : V
i : Fin (finrank R V) := ⟨0, ⋯⟩
hfv : f (b i) * (b.repr v) i = 0
this : ∀ (x : V), x = (b.repr x) i • b i
⊢ f ((b.repr x) i • b i) • v = 0
Module: Mathlib.LinearAlgebra.Transvection.Basic

Goal state before:
pp: R : Type u_1
V : Type u_2
inst✝² : Ring R
inst✝¹ : AddCommGroup V
inst✝ : Module R V
f : Dual R V
v : V
h : IsUnit (1 + f v)
x : V
⊢ 1 = ↑1 * ↑h.unit⁻¹ + f v * ↑h.unit⁻¹

Tactic:
← add_mul

Goal state after:
R : Type u_1
V : Type u_2
inst✝² : Ring R
inst✝¹ : AddCommGroup V
inst✝ : Module R V
f : Dual R V
v : V
h : IsUnit (1 + f v)
x : V
⊢ 1 = (↑1 + f v) * ↑h.unit⁻¹
Module: Mathlib.LinearAlgebra.CliffordAlgebra.BaseChange

Goal state before:
pp: R : Type u_1
A : Type u_2
V : Type u_3
inst✝⁵ : CommRing R
inst✝⁴ : CommRing A
inst✝³ : AddCommGroup V
inst✝² : Algebra R A
inst✝¹ : Module R V
inst✝ : Invertible 2
Q : QuadraticForm R V
⊢ { f // ∀ (m : V), f m * f m = (algebraMap R (CliffordAlgebra (QuadraticForm.baseChange A Q))) (Q m) }

Tactic:
refine ⟨(ι (Q.baseChange A)).restrictScalars R ∘ₗ TensorProduct.mk R A V 1, fun v => ?_⟩

Goal state after:
R : Type u_1
A : Type u_2
V : Type u_3
inst✝⁵ : CommRing R
inst✝⁴ : CommRing A
inst✝³ : AddCommGroup V
inst✝² : Algebra R A
inst✝¹ : Module R V
inst✝ : Invertible 2
Q : QuadraticForm R V
v : V
⊢ (↑R (ι (QuadraticForm.baseChange A Q)) ∘ₗ (TensorProduct.mk R A V) 1) v *
      (↑R (ι (QuadraticForm.baseChange A Q)) ∘ₗ (TensorProduct.mk R A V) 1) v =
    (algebraMap R (CliffordAlgebra (QuadraticForm.baseChange A Q))) (Q v)
Module: Mathlib.LinearAlgebra.CliffordAlgebra.BaseChange

Goal state before:
pp: R : Type u_1
A : Type u_2
V : Type u_3
inst✝⁵ : CommRing R
inst✝⁴ : CommRing A
inst✝³ : AddCommGroup V
inst✝² : Algebra R A
inst✝¹ : Module R V
inst✝ : Invertible 2
Q : QuadraticForm R V
z : A
⊢ (algebraMap A (CliffordAlgebra (QuadraticForm.baseChange A Q))) z * (ofBaseChangeAux A Q) 1 =
    (algebraMap A (CliffordAlgebra (QuadraticForm.baseChange A Q))) z

Tactic:
rw [map_one, mul_one]

Goal state after:
Module: Mathlib.LinearAlgebra.CliffordAlgebra.BaseChange

Goal state before:
pp: R : Type u_1
A : Type u_2
V : Type u_3
inst✝⁵ : CommRing R
inst✝⁴ : CommRing A
inst✝³ : AddCommGroup V
inst✝² : Algebra R A
inst✝¹ : Module R V
inst✝ : Invertible 2
Q : QuadraticForm R V
x : CliffordAlgebra (QuadraticForm.baseChange A Q)
⊢ (TensorProduct.AlgebraTensorModule.map (↑(opLinearEquiv A).symm ∘ₗ (↑(AlgEquiv.toOpposite A A)).toLinearMap)
        (↑(opLinearEquiv R).symm ∘ₗ reverseOp.toLinearMap))
      (↑(toBaseChange A Q) x) =
    (TensorProduct.map LinearMap.id reverse) ((toBaseChange A Q) x)

Tactic:
reverse,

Goal state after:
R : Type u_1
A : Type u_2
V : Type u_3
inst✝⁵ : CommRing R
inst✝⁴ : CommRing A
inst✝³ : AddCommGroup V
inst✝² : Algebra R A
inst✝¹ : Module R V
inst✝ : Invertible 2
Q : QuadraticForm R V
x : CliffordAlgebra (QuadraticForm.baseChange A Q)
⊢ (TensorProduct.AlgebraTensorModule.map (↑(opLinearEquiv A).symm ∘ₗ (↑(AlgEquiv.toOpposite A A)).toLinearMap)
        (↑(opLinearEquiv R).symm ∘ₗ reverseOp.toLinearMap))
      (↑(toBaseChange A Q) x) =
    (TensorProduct.map LinearMap.id (↑(opLinearEquiv R).symm ∘ₗ reverseOp.toLinearMap)) ((toBaseChange A Q) x)
Module: Mathlib.LinearAlgebra.CliffordAlgebra.EvenEquiv

Goal state before:
pp: R : Type u_1
M : Type u_2
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
Q : QuadraticForm R M
m : M
r : R
⊢ (ι (Q' Q)) (m, r) = (v Q) m + r • e0 Q

Tactic:
e0,

Goal state after:
R : Type u_1
M : Type u_2
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
Q : QuadraticForm R M
m : M
r : R
⊢ (ι (Q' Q)) (m, r) = (v Q) m + r • (ι (Q' Q)) (0, 1)
Module: Mathlib.LinearAlgebra.Transvection.Basic

Goal state before:
pp: case h₀
K : Type u_3
V : Type u_4
inst✝³ : Field K
inst✝² : AddCommGroup V
inst✝¹ : Module K V
inst✝ : FiniteDimensional K V
f : Dual K V
v : V
hfv : ¬f v = 0
ι : Set V
b : Basis (↑ι) K V
i : ↑ι
hv : v = b i
hf : f = f v • b.coord i
this✝ : Fintype ↑ι
this : (toMatrix b b) (transvection f v) = Matrix.diagonal (Function.update 1 i (1 + f v))
⊢ ∀ b ∈ Finset.univ, b ≠ i → Function.update 1 i (1 + f v) b = 1

Tactic:
intro j _ hj
        simp [Function.update_of_ne hj]

Goal state after:
Module: Mathlib.LinearAlgebra.CliffordAlgebra.Even

Goal state before:
pp: case algebraMap
R : Type u_1
M : Type u_2
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup M
inst✝² : Module R M
Q : QuadraticForm R M
A : Type u_3
inst✝¹ : Ring A
inst✝ : Algebra R A
f g : ↥(even Q) →ₐ[R] A
h : ((ι Q).compr₂ f).bilin = ((ι Q).compr₂ g).bilin
x : CliffordAlgebra Q
r : R
⊢ f ⟨(algebraMap R (CliffordAlgebra Q)) r, ⋯⟩ = g ⟨(algebraMap R (CliffordAlgebra Q)) r, ⋯⟩

Tactic:
exact (f.commutes r).trans (g.commutes r).symm

Goal state after:
Module: Mathlib.LinearAlgebra.CliffordAlgebra.EvenEquiv

Goal state before:
pp: R : Type u_1
M : Type u_2
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
Q : QuadraticForm R M
m : M
⊢ ↑((LinearMap.codRestrict (Subalgebra.toSubmodule (even (Q' Q))) (LinearMap.mulLeft R (e0 Q) ∘ₗ v Q) ⋯) m) =
    e0 Q * (v Q) m

Tactic:
rw [LinearMap.codRestrict_apply, LinearMap.coe_comp, Function.comp_apply, LinearMap.mulLeft_apply]

Goal state after:
Module: Mathlib.LinearAlgebra.Transvection.Basic

Goal state before:
pp: R : Type u_3
V : Type u_4
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup V
inst✝² : Module R V
inst✝¹ : Free R V
inst✝ : Module.Finite R V
f : Dual R V
v : V
hR : Nontrivial R
n : ℕ := finrank R V
b : Basis (Fin n) R V
S : Type := MvPolynomial (Fin n ⊕ Fin n) ℤ
γ : S →+* R := ↑(MvPolynomial.aeval (Sum.elim (fun i ↦ f (b i)) fun i ↦ (b.coord i) v))
this : IsDomain S
x✝² : Algebra S R := γ.toAlgebra
x✝¹ : Module S V := compHom V γ
x✝ : IsScalarTower S R V
ε : (Fin n → S) →ₗ[S] V := Fintype.linearCombination S fun i ↦ b i
ibc : IsBaseChange R ε
M : Type := Fin n → S
i : Fin n
⊢ ε (Pi.single i 1) = b i

Tactic:
rw [Fintype.linearCombination_apply_single, one_smul]

Goal state after:
Module: Mathlib.LinearAlgebra.Transvection.Basic

Goal state before:
pp: R : Type u_3
V : Type u_4
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup V
inst✝² : Module R V
inst✝¹ : Free R V
inst✝ : Module.Finite R V
f : Dual R V
v : V
hR : Nontrivial R
n : ℕ := finrank R V
b : Basis (Fin n) R V
S : Type := MvPolynomial (Fin n ⊕ Fin n) ℤ
γ : S →+* R := ↑(MvPolynomial.aeval (Sum.elim (fun i ↦ f (b i)) fun i ↦ (b.coord i) v))
this : IsDomain S
x✝² : Algebra S R := γ.toAlgebra
x✝¹ : Module S V := compHom V γ
x✝ : IsScalarTower S R V
ε : (Fin n → S) →ₗ[S] V := Fintype.linearCombination S fun i ↦ b i
ibc : IsBaseChange R ε
M : Type := Fin n → S
hε : ∀ (i : Fin n), ε (Pi.single i 1) = b i
fM : Dual S M := Fintype.linearCombination S fun i ↦ MvPolynomial.X (Sum.inl i)
vM : M := fun i ↦ MvPolynomial.X (Sum.inr i)
hf : ibc.toDual fM = f
⊢ ε vM = v

Tactic:
of_fintype_basis_eq

Goal state after:
R : Type u_3
V : Type u_4
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup V
inst✝² : Module R V
inst✝¹ : Free R V
inst✝ : Module.Finite R V
f : Dual R V
v : V
hR : Nontrivial R
n : ℕ := finrank R V
b : Basis (Fin n) R V
S : Type := MvPolynomial (Fin n ⊕ Fin n) ℤ
γ : S →+* R := ↑(MvPolynomial.aeval (Sum.elim (fun i ↦ f (b i)) fun i ↦ (b.coord i) v))
this : IsDomain S
x✝² : Algebra S R := γ.toAlgebra
x✝¹ : Module S V := compHom V γ
x✝ : IsScalarTower S R V
ε : (Fin n → S) →ₗ[S] V := Fintype.linearCombination S fun i ↦ b i
ibc : IsBaseChange R ε
M : Type := Fin n → S
hε : ∀ (i : Fin n), ε (Pi.single i 1) = b i
fM : Dual S M := Fintype.linearCombination S fun i ↦ MvPolynomial.X (Sum.inl i)
vM : M := fun i ↦ MvPolynomial.X (Sum.inr i)
hf : ibc.toDual fM = f
⊢ ⇑(algebraMap S R) ∘ vM = b.equivFun v
Module: Mathlib.LinearAlgebra.CliffordAlgebra.SpinGroup

Goal state before:
pp: R : Type u_1
inst✝² : CommRing R
M : Type u_2
inst✝¹ : AddCommGroup M
inst✝ : Module R M
Q : QuadraticForm R M
x : CliffordAlgebra Q
y : (CliffordAlgebra Q)ˣ
hy₂ : (Units.coeHom (CliffordAlgebra Q)) y = x
_hx₂ : star x * x = 1
hx₃ : x * star x = 1
hy₁ : y ∈ lipschitzGroup Q
⊢ star x ∈ Submonoid.map (Units.coeHom (CliffordAlgebra Q)) (lipschitzGroup Q).toSubmonoid

Tactic:
simp only [Units.coeHom_apply] at hy₂

Goal state after:
R : Type u_1
inst✝² : CommRing R
M : Type u_2
inst✝¹ : AddCommGroup M
inst✝ : Module R M
Q : QuadraticForm R M
x : CliffordAlgebra Q
y : (CliffordAlgebra Q)ˣ
hy₂ : ↑y = x
_hx₂ : star x * x = 1
hx₃ : x * star x = 1
hy₁ : y ∈ lipschitzGroup Q
⊢ star x ∈ Submonoid.map (Units.coeHom (CliffordAlgebra Q)) (lipschitzGroup Q).toSubmonoid
Module: Mathlib.LinearAlgebra.FreeModule.ModN

Goal state before:
pp: G : Type u_1
H : Type u_2
M : Type u_3
inst✝¹ : AddCommGroup G
n : ℕ
inst✝ : AddMonoid M
f : ModN G n →+ M
g : G
⊢ n • (f.comp (QuotientAddGroup.mk' ((LinearMap.lsmul ℤ G) ↑n).range.toAddSubgroup)) g = 0

Tactic:
let Gn : AddSubgroup G := (LinearMap.range (LinearMap.lsmul ℤ G n)).toAddSubgroup
    suffices n • g ∈ (QuotientAddGroup.mk' Gn).ker by
      simp only [AddMonoidHom.coe_comp, comp_apply, ← map_nsmul]
      change f (QuotientAddGroup.mk' Gn (n • g)) = 0 -- Can we avoid `change`?
      rw [this, map_zero]
    simp [QuotientAddGroup.ker_mk', Gn]

Goal state after:
Module: Mathlib.LinearAlgebra.Matrix.Determinant.Misc

Goal state before:
pp: case pos
R : Type u_1
inst✝ : CommRing R
n : ℕ
M : Matrix (Fin (n + 1)) (Fin n) R
j₁ j₂ : Fin (n + 1)
i : Fin n
h_ind : (M.submatrix i.castSucc.succAbove id).det = (↑↑i.castSucc).negOnePow • (M.submatrix (Fin.succAbove 0) id).det
a b : Fin n
h : a = i
hv : (∑ j, M j) b = 0 b
⊢ -∑ x, M (i.succ.succAbove x) b = M (i.castSucc.succAbove a) b

Tactic:
rw [Fin.sum_univ_succAbove _ i.succ, Pi.add_apply, Finset.sum_apply] at hv

Goal state after:
case pos
R : Type u_1
inst✝ : CommRing R
n : ℕ
M : Matrix (Fin (n + 1)) (Fin n) R
j₁ j₂ : Fin (n + 1)
i : Fin n
h_ind : (M.submatrix i.castSucc.succAbove id).det = (↑↑i.castSucc).negOnePow • (M.submatrix (Fin.succAbove 0) id).det
a b : Fin n
h : a = i
hv : M i.succ b + ∑ c, M (i.succ.succAbove c) b = 0 b
⊢ -∑ x, M (i.succ.succAbove x) b = M (i.castSucc.succAbove a) b
Module: Mathlib.LinearAlgebra.Matrix.Nonsingular

Goal state before:
pp: R : Type u_1
m✝ : Type u_2
n✝ : Type u_3
inst✝⁵ : CommSemiring R
inst✝⁴ : Fintype m✝
inst✝³ : Fintype n✝
inst✝² : DecidableEq m✝
inst✝¹ : DecidableEq n✝
A✝ : Matrix n✝ n✝ R
inst✝ : Nontrivial R
n m : ℕ
f : (Fin n → R) →ₗ[R] Fin m → R
hf : Function.Injective ⇑f
g : (Fin m → R) →ₗ[R] Fin n → R := LinearMap.pi fun i ↦ if h : ↑i < m then LinearMap.proj ⟨↑i, h⟩ else 0
hnm : m < n
hg : Function.Injective ⇑g
A : Matrix (Fin n) (Fin n) R := LinearMap.toMatrix' (g ∘ₗ f)
⊢ Function.Injective A.mulVec

Tactic:
convert hg.comp hf; ext; simp [A, g]

Goal state after:
Module: Mathlib.LinearAlgebra.Projectivization.Subspace

Goal state before:
pp: K : Type u_1
V : Type u_2
inst✝² : DivisionRing K
inst✝¹ : AddCommGroup V
inst✝ : Module K V
S : Set (ℙ K V)
u : ℙ K V
⊢ u ∈ span S ↔ ∀ (W : Subspace K V), S ⊆ ↑W → u ∈ W

Tactic:
by
  simp_rw [← span_le_subspace_iff]
  exact ⟨fun hu W hW => hW hu, fun W => W (span S) (le_refl _)⟩

Goal state after:
Module: Mathlib.LinearAlgebra.Projectivization.Subspace

Goal state before:
pp: K : Type u_1
V : Type u_2
inst✝² : DivisionRing K
inst✝¹ : AddCommGroup V
inst✝ : Module K V
s : Subspace K V
c : K
x : V
h₁ : x ∈ {x | ∀ (h : x ≠ 0), Projectivization.mk K x h ∈ s.carrier}
h₂ : c • x ≠ 0
⊢ Projectivization.mk K (c • x) h₂ = Projectivization.mk K x ⋯

Tactic:
Projectivization.mk_eq_mk_iff'

Goal state after:
K : Type u_1
V : Type u_2
inst✝² : DivisionRing K
inst✝¹ : AddCommGroup V
inst✝ : Module K V
s : Subspace K V
c : K
x : V
h₁ : x ∈ {x | ∀ (h : x ≠ 0), Projectivization.mk K x h ∈ s.carrier}
h₂ : c • x ≠ 0
⊢ ∃ a, a • x = c • x
Module: Mathlib.LinearAlgebra.Projectivization.Action

Goal state before:
pp: K : Type u_1
V : Type u_2
inst✝² : AddCommGroup V
inst✝¹ : Field K
inst✝ : Module K V
this✝ : ∀ {a b c d : ℙ K V}, a ≠ b → c ≠ d → ∃ g, g • a = c ∧ g • b = d
D D' E E' : ℙ K V
hD : D ≠ D'
hE : E ≠ E'
g : V ≃ₗ[K] V
gD : g • D = E
gE : g • D' = E'
hV : FiniteDimensional K V
this : ∀ (a : Kˣ), ∃ h, LinearEquiv.det h = a ∧ h • D = D ∧ h • D' = D'
⊢ ∃ g, g • D = E ∧ g • D' = E'

Tactic:
obtain ⟨h, hdet, hD, hE⟩ := this (g.det)⁻¹
      use ⟨g * h, by simp [hdet]⟩
      simp [specialLinearGroup_smul_def, toLinearEquiv_eq_coe, mul_smul, gD, hD, gE, hE]

Goal state after:
Module: Mathlib.LinearAlgebra.Projectivization.PSL.PSL2

Goal state before:
pp: F : Type u_2
inst✝ : Field F
hF : 4 ≤ Nat.card F
this : Finite F
x : Fˣ
hx : Function.Surjective fun x_1 ↦ x ^ x_1
h : ↑x ^ 2 = 1
⊢ False

Tactic:
grw [Nat.card_eq_card_units_add_one F, ← orderOf_eq_card_of_forall_mem_zpowers hx,
    orderOf_le_of_pow_eq_one zero_lt_two (Units.ext <| by simpa using h)] at hF

Goal state after:
F : Type u_2
inst✝ : Field F
this : Finite F
x : Fˣ
hF : 4 ≤ 2 + 1
hx : Function.Surjective fun x_1 ↦ x ^ x_1
h : ↑x ^ 2 = 1
⊢ False
Module: Mathlib.LinearAlgebra.SpecialLinearGroup

Goal state before:
pp: case pos
R : Type u_4
inst✝⁶ : CommRing R
V : Type u_5
inst✝⁵ : AddCommGroup V
inst✝⁴ : Module R V
inst✝³ : Module.Free R V
inst✝² : Module.Finite R V
ι : Type u_6
inst✝¹ : Fintype ι
inst✝ : DecidableEq ι
b : Module.Basis ι R V
g : ↥(center (Matrix.SpecialLinearGroup ι R))
a✝ : Nontrivial R
hV : Subsingleton V
⊢ ↑(((centerCongr (toLin_equiv b)).trans centerEquivRootsOfUnity) g) = ↑(center_equiv_rootsOfUnity g)

Tactic:
convert! Eq.refl (1 : Rˣ)

Goal state after:
case e'_2
R : Type u_4
inst✝⁶ : CommRing R
V : Type u_5
inst✝⁵ : AddCommGroup V
inst✝⁴ : Module R V
inst✝³ : Module.Free R V
inst✝² : Module.Finite R V
ι : Type u_6
inst✝¹ : Fintype ι
inst✝ : DecidableEq ι
b : Module.Basis ι R V
g : ↥(center (Matrix.SpecialLinearGroup ι R))
a✝ : Nontrivial R
hV : Subsingleton V
⊢ ↑(((centerCongr (toLin_equiv b)).trans centerEquivRootsOfUnity) g) = 1

case e'_3
R : Type u_4
inst✝⁶ : CommRing R
V : Type u_5
inst✝⁵ : AddCommGroup V
inst✝⁴ : Module R V
inst✝³ : Module.Free R V
inst✝² : Module.Finite R V
ι : Type u_6
inst✝¹ : Fintype ι
inst✝ : DecidableEq ι
b : Module.Basis ι R V
g : ↥(center (Matrix.SpecialLinearGroup ι R))
a✝ : Nontrivial R
hV : Subsingleton V
⊢ ↑(center_equiv_rootsOfUnity g) = 1
Module: Mathlib.LinearAlgebra.QuadraticForm.Signature

Goal state before:
pp: case e'_2
R : Type u_1
M : Type u_2
M' : Type u_3
inst✝⁵ : AddCommGroup M
inst✝⁴ : AddCommGroup M'
inst✝³ : CommRing R
inst✝² : LinearOrder R
inst✝¹ : Module R M
Q : QuadraticForm R M
inst✝ : Module R M'
Q' : QuadraticForm R M'
e : IsometryEquiv Q Q'
V : Submodule R M
⊢ ∀ (j : ℕ), Module.finrank R ↥V = j ↔ Module.finrank R ↥((Submodule.orderIsoMapComap e.toLinearEquiv).toEquiv V) = j

Tactic:
rw [eq_iff_eq_cancel_right]

Goal state after:
case e'_2
R : Type u_1
M : Type u_2
M' : Type u_3
inst✝⁵ : AddCommGroup M
inst✝⁴ : AddCommGroup M'
inst✝³ : CommRing R
inst✝² : LinearOrder R
inst✝¹ : Module R M
Q : QuadraticForm R M
inst✝ : Module R M'
Q' : QuadraticForm R M'
e : IsometryEquiv Q Q'
V : Submodule R M
⊢ Module.finrank R ↥V = Module.finrank R ↥((Submodule.orderIsoMapComap e.toLinearEquiv).toEquiv V)
Module: Mathlib.LinearAlgebra.RootSystem.GeckConstruction.Semisimple

Goal state before:
pp: case inr
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝¹⁰ : CommRing R
inst✝⁹ : IsDomain R
inst✝⁸ : CharZero R
inst✝⁷ : AddCommGroup M
inst✝⁶ : Module R M
inst✝⁵ : AddCommGroup N
inst✝⁴ : Module R N
P : RootPairing ι R M N
inst✝³ : P.IsCrystallographic
inst✝² : P.IsReduced
b : P.Base
inst✝¹ : Fintype ι
inst✝ : DecidableEq ι
i : ↥b.support
j : ι
h : j ≠ -↑i
this✝¹ : Module.IsReflexive R M
this✝ : IsAddTorsionFree M
this : InvolutiveNeg ι := P.indexNeg
aux : ∀ (n : ℕ), (e i ^ (n + 1)).col (Sum.inr j) = e i *ᵥ (e i ^ n).col (Sum.inr j)
n x : ℕ
hk₂ : (e i ^ n).col (Sum.inr j) = x • Pi.single (Sum.inr (-↑i)) 1
hk₁ : P.root (-j) = (n + 1) • P.root ↑i
hn : n > 0
⊢ False

Tactic:
have _i : (n + 1).AtLeastTwo := ⟨by lia⟩

Goal state after:
case inr
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝¹⁰ : CommRing R
inst✝⁹ : IsDomain R
inst✝⁸ : CharZero R
inst✝⁷ : AddCommGroup M
inst✝⁶ : Module R M
inst✝⁵ : AddCommGroup N
inst✝⁴ : Module R N
P : RootPairing ι R M N
inst✝³ : P.IsCrystallographic
inst✝² : P.IsReduced
b : P.Base
inst✝¹ : Fintype ι
inst✝ : DecidableEq ι
i : ↥b.support
j : ι
h : j ≠ -↑i
this✝¹ : Module.IsReflexive R M
this✝ : IsAddTorsionFree M
this : InvolutiveNeg ι := P.indexNeg
aux : ∀ (n : ℕ), (e i ^ (n + 1)).col (Sum.inr j) = e i *ᵥ (e i ^ n).col (Sum.inr j)
n x : ℕ
hk₂ : (e i ^ n).col (Sum.inr j) = x • Pi.single (Sum.inr (-↑i)) 1
hk₁ : P.root (-j) = (n + 1) • P.root ↑i
hn : n > 0
_i : (n + 1).AtLeastTwo
⊢ False
Module: Mathlib.LinearAlgebra.RootSystem.GeckConstruction.Basic

Goal state before:
pp: case inl
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝¹⁰ : CommRing R
inst✝⁹ : AddCommGroup M
inst✝⁸ : Module R M
inst✝⁷ : AddCommGroup N
inst✝⁶ : Module R N
P : RootPairing ι R M N
inst✝⁵ : P.IsCrystallographic
b : P.Base
inst✝⁴ : Finite ι
inst✝³ : IsDomain R
inst✝² : CharZero R
inst✝¹ : DecidableEq ι
inst✝ : Fintype ι
i j : ι
k : ↥b.support
h : P.root i = P.root j + P.root ↑k
l : ↥b.support
⊢ ⁅f k, v b i⁆ (Sum.inl l) = ((↑(chainTopCoeff (↑k) i) + 1) • v b j) (Sum.inl l)

Tactic:
replace h : i ≠ k := by rintro rfl; exact P.ne_zero j <| by simpa using h

Goal state after:
case inl
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝¹⁰ : CommRing R
inst✝⁹ : AddCommGroup M
inst✝⁸ : Module R M
inst✝⁷ : AddCommGroup N
inst✝⁶ : Module R N
P : RootPairing ι R M N
inst✝⁵ : P.IsCrystallographic
b : P.Base
inst✝⁴ : Finite ι
inst✝³ : IsDomain R
inst✝² : CharZero R
inst✝¹ : DecidableEq ι
inst✝ : Fintype ι
i j : ι
k l : ↥b.support
h : i ≠ ↑k
⊢ ⁅f k, v b i⁆ (Sum.inl l) = ((↑(chainTopCoeff (↑k) i) + 1) • v b j) (Sum.inl l)
Module: Mathlib.LinearAlgebra.RootSystem.GeckConstruction.Basic

Goal state before:
pp: ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝¹⁰ : CommRing R
inst✝⁹ : AddCommGroup M
inst✝⁸ : Module R M
inst✝⁷ : AddCommGroup N
inst✝⁶ : Module R N
P : RootPairing ι R M N
inst✝⁵ : P.IsCrystallographic
b : P.Base
inst✝⁴ : Finite ι
inst✝³ : IsDomain R
inst✝² : CharZero R
inst✝¹ : DecidableEq ι
inst✝ : Fintype ι
x : Matrix (↥b.support ⊕ ι) (↥b.support ⊕ ι) R
i : ↥b.support
hu : f i ∈ range h ∪ range e ∪ range f
⊢ (ωConj b) (f i) ∈ range h ∪ range e ∪ range f

Tactic:
simp [ω_mul_f, mul_assoc]

Goal state after: