mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.RingTheory.Localization.LocalizationLocalization

Goal state before:
pp: case refine_1
R : Type u_1
inst✝⁸ : CommSemiring R
M : Submonoid R
S : Type u_2
inst✝⁷ : CommSemiring S
inst✝⁶ : Algebra R S
N : Submonoid S
T : Type u_3
inst✝⁵ : CommSemiring T
inst✝⁴ : Algebra R T
inst✝³ : Algebra S T
inst✝² : IsScalarTower R S T
inst✝¹ : IsLocalization M S
inst✝ : IsLocalization N T
x : T
y : S
s : ↥N
eq₁ : x * (algebraMap S T) ↑s = (algebraMap S T) y
z : R
t : ↥M
eq₂ : y * (algebraMap R S) ↑t = (algebraMap R S) z
z' : R
t' : ↥M
eq₃ : ↑s * (algebraMap R S) ↑t' = (algebraMap R S) z'
⊢ ↑s * (algebraMap R S) ↑t' * (algebraMap R S) ↑t = ↑s * (algebraMap R S) ↑(t * t')

Tactic:
mul_assoc,

Goal state after:
case refine_1
R : Type u_1
inst✝⁸ : CommSemiring R
M : Submonoid R
S : Type u_2
inst✝⁷ : CommSemiring S
inst✝⁶ : Algebra R S
N : Submonoid S
T : Type u_3
inst✝⁵ : CommSemiring T
inst✝⁴ : Algebra R T
inst✝³ : Algebra S T
inst✝² : IsScalarTower R S T
inst✝¹ : IsLocalization M S
inst✝ : IsLocalization N T
x : T
y : S
s : ↥N
eq₁ : x * (algebraMap S T) ↑s = (algebraMap S T) y
z : R
t : ↥M
eq₂ : y * (algebraMap R S) ↑t = (algebraMap R S) z
z' : R
t' : ↥M
eq₃ : ↑s * (algebraMap R S) ↑t' = (algebraMap R S) z'
⊢ ↑s * ((algebraMap R S) ↑t' * (algebraMap R S) ↑t) = ↑s * (algebraMap R S) ↑(t * t')
Module: Mathlib.RingTheory.Localization.LocalizationLocalization

Goal state before:
pp: case h
R : Type u_1
inst✝⁸ : CommRing R
M : Submonoid R
S : Type u_2
T : Type u_3
inst✝⁷ : CommRing S
inst✝⁶ : CommRing T
inst✝⁵ : Algebra R S
inst✝⁴ : Algebra R T
inst✝³ : Algebra S T
inst✝² : IsScalarTower R S T
inst✝¹ : IsLocalization M S
inst✝ : IsFractionRing R T
hM : M ≤ nonZeroDivisors R
this : IsLocalization (Submonoid.map (algebraMap R S) (nonZeroDivisors R)) T
x : S
left✝ : x ∈ ↑(nonZeroDivisorsLeft S)
hx : x ∈ ↑(nonZeroDivisorsRight S)
y : R
s : ↥M
e : x * (algebraMap R S) ↑(y, s).2 = (algebraMap R S) (y, s).1
z : R
hz : z * (y, s).1 = 0
⊢ (algebraMap R S) z * x * (algebraMap R S) ↑s = 0 * (algebraMap R S) ↑s

Tactic:
mul_assoc,

Goal state after:
case h
R : Type u_1
inst✝⁸ : CommRing R
M : Submonoid R
S : Type u_2
T : Type u_3
inst✝⁷ : CommRing S
inst✝⁶ : CommRing T
inst✝⁵ : Algebra R S
inst✝⁴ : Algebra R T
inst✝³ : Algebra S T
inst✝² : IsScalarTower R S T
inst✝¹ : IsLocalization M S
inst✝ : IsFractionRing R T
hM : M ≤ nonZeroDivisors R
this : IsLocalization (Submonoid.map (algebraMap R S) (nonZeroDivisors R)) T
x : S
left✝ : x ∈ ↑(nonZeroDivisorsLeft S)
hx : x ∈ ↑(nonZeroDivisorsRight S)
y : R
s : ↥M
e : x * (algebraMap R S) ↑(y, s).2 = (algebraMap R S) (y, s).1
z : R
hz : z * (y, s).1 = 0
⊢ (algebraMap R S) z * (x * (algebraMap R S) ↑s) = 0 * (algebraMap R S) ↑s
Module: Mathlib.RingTheory.Localization.AtPrime.Basic

Goal state before:
pp: R : Type u_1
inst✝⁵ : CommSemiring R
p : Ideal R
inst✝⁴ : p.IsPrime
Rₚ : Type u_4
inst✝³ : CommSemiring Rₚ
inst✝² : Algebra R Rₚ
inst✝¹ : IsLocalization.AtPrime Rₚ p
inst✝ : IsLocalRing Rₚ
⊢ Ideal.map (algebraMap R Rₚ) p = maximalIdeal Rₚ

Tactic:
convert! congr_arg (Ideal.map (algebraMap R Rₚ)) (under_maximalIdeal Rₚ p).symm
  rw [map_under p.primeCompl]

Goal state after:
Module: Mathlib.RingTheory.Localization.Submodule

Goal state before:
pp: case mp.refine_3.e_a
R : Type u_1
inst✝⁷ : CommSemiring R
M : Submonoid R
S : Type u_2
inst✝⁶ : CommSemiring S
inst✝⁵ : Algebra R S
inst✝⁴ : IsLocalization M S
N : Type u_3
inst✝³ : AddCommMonoid N
inst✝² : Module R N
inst✝¹ : Module S N
inst✝ : IsScalarTower R S N
x : N
a : Set N
h : x ∈ Submodule.span S a
y : N
hy : y ∈ Submodule.span R a
z : ↥M
hx✝ : mk' S 1 z • y ∈ Submodule.span S a
y' : N
hy' : y' ∈ Submodule.span R a
z' : ↥M
hy✝ : mk' S 1 z' • y' ∈ Submodule.span S a
⊢ mk' S (1 * 1) z • y = (mk' S 1 z * mk' S 1 z' * (algebraMap R S) ↑z') • y

Tactic:
mul_assoc,

Goal state after:
case mp.refine_3.e_a
R : Type u_1
inst✝⁷ : CommSemiring R
M : Submonoid R
S : Type u_2
inst✝⁶ : CommSemiring S
inst✝⁵ : Algebra R S
inst✝⁴ : IsLocalization M S
N : Type u_3
inst✝³ : AddCommMonoid N
inst✝² : Module R N
inst✝¹ : Module S N
inst✝ : IsScalarTower R S N
x : N
a : Set N
h : x ∈ Submodule.span S a
y : N
hy : y ∈ Submodule.span R a
z : ↥M
hx✝ : mk' S 1 z • y ∈ Submodule.span S a
y' : N
hy' : y' ∈ Submodule.span R a
z' : ↥M
hy✝ : mk' S 1 z' • y' ∈ Submodule.span S a
⊢ mk' S (1 * 1) z • y = (mk' S 1 z * (mk' S 1 z' * (algebraMap R S) ↑z')) • y
Module: Mathlib.RingTheory.Localization.AtPrime.Basic

Goal state before:
pp: R : Type u_7
inst✝⁵ : CommRing R
p : Ideal R
inst✝⁴ : p.IsMaximal
Rₚ : Type u_8
inst✝³ : CommRing Rₚ
inst✝² : Algebra R Rₚ
inst✝¹ : IsLocalization.AtPrime Rₚ p
inst✝ : IsLocalRing Rₚ
x : R
s : ↥p.primeCompl
h₁ : (Ideal.Quotient.mk p) ↑s ≠ 0
h₂ : (equivQuotMaximalIdeal p Rₚ) ((Ideal.Quotient.mk p) ↑s) ≠ 0
⊢ (Ideal.Quotient.mk (maximalIdeal Rₚ)) (mk' Rₚ x s) * (equivQuotMaximalIdeal p Rₚ) ((Ideal.Quotient.mk p) ↑s) =
    (equivQuotMaximalIdeal p Rₚ) ((Ideal.Quotient.mk p) x) * (equivQuotMaximalIdeal p Rₚ) ((Ideal.Quotient.mk p) ↑s)⁻¹ *
      (equivQuotMaximalIdeal p Rₚ) ((Ideal.Quotient.mk p) ↑s)

Tactic:
mul_assoc,

Goal state after:
R : Type u_7
inst✝⁵ : CommRing R
p : Ideal R
inst✝⁴ : p.IsMaximal
Rₚ : Type u_8
inst✝³ : CommRing Rₚ
inst✝² : Algebra R Rₚ
inst✝¹ : IsLocalization.AtPrime Rₚ p
inst✝ : IsLocalRing Rₚ
x : R
s : ↥p.primeCompl
h₁ : (Ideal.Quotient.mk p) ↑s ≠ 0
h₂ : (equivQuotMaximalIdeal p Rₚ) ((Ideal.Quotient.mk p) ↑s) ≠ 0
⊢ (Ideal.Quotient.mk (maximalIdeal Rₚ)) (mk' Rₚ x s) * (equivQuotMaximalIdeal p Rₚ) ((Ideal.Quotient.mk p) ↑s) =
    (equivQuotMaximalIdeal p Rₚ) ((Ideal.Quotient.mk p) x) *
      ((equivQuotMaximalIdeal p Rₚ) ((Ideal.Quotient.mk p) ↑s)⁻¹ *
        (equivQuotMaximalIdeal p Rₚ) ((Ideal.Quotient.mk p) ↑s))
Module: Mathlib.Algebra.Ring.Regular

Goal state before:
pp: α : Type u_1
inst✝ : Ring α
h : ∀ (x y z : α), x * z = 1 → y * z = 1 → x = y
x y : α
eq : x * y = 1
⊢ 1 * y - y * x * y + x * y = 1

Tactic:
mul_assoc,

Goal state after:
α : Type u_1
inst✝ : Ring α
h : ∀ (x y z : α), x * z = 1 → y * z = 1 → x = y
x y : α
eq : x * y = 1
⊢ 1 * y - y * (x * y) + x * y = 1
Module: Mathlib.RingTheory.Localization.AtPrime.Basic

Goal state before:
pp: S : Type u_6
R : Type u_7
inst✝⁸ : CommRing R
p : Ideal R
inst✝⁷ : p.IsMaximal
Sₚ : Type u_9
inst✝⁶ : CommRing S
inst✝⁵ : Algebra R S
inst✝⁴ : CommRing Sₚ
inst✝³ : Algebra S Sₚ
inst✝² : Algebra R Sₚ
inst✝¹ : IsLocalization (algebraMapSubmonoid S p.primeCompl) Sₚ
inst✝ : IsScalarTower R S Sₚ
x : S
hx : x ∈ comap (algebraMap S Sₚ) (Ideal.map (algebraMap S Sₚ) pS)
y : ↥pS
s c : ↥(algebraMapSubmonoid S p.primeCompl)
hc : ↑c * (x * ↑(y, s).2) = ↑c * ↑(y, s).1
α : R
hα : α ∈ ↑p.primeCompl
e : (algebraMap R S) α = ↑(c * s)
⊢ ↑c * ↑s * x ∈ pS

Tactic:
mul_assoc,

Goal state after:
S : Type u_6
R : Type u_7
inst✝⁸ : CommRing R
p : Ideal R
inst✝⁷ : p.IsMaximal
Sₚ : Type u_9
inst✝⁶ : CommRing S
inst✝⁵ : Algebra R S
inst✝⁴ : CommRing Sₚ
inst✝³ : Algebra S Sₚ
inst✝² : Algebra R Sₚ
inst✝¹ : IsLocalization (algebraMapSubmonoid S p.primeCompl) Sₚ
inst✝ : IsScalarTower R S Sₚ
x : S
hx : x ∈ comap (algebraMap S Sₚ) (Ideal.map (algebraMap S Sₚ) pS)
y : ↥pS
s c : ↥(algebraMapSubmonoid S p.primeCompl)
hc : ↑c * (x * ↑(y, s).2) = ↑c * ↑(y, s).1
α : R
hα : α ∈ ↑p.primeCompl
e : (algebraMap R S) α = ↑(c * s)
⊢ ↑c * (↑s * x) ∈ pS
Module: Mathlib.RingTheory.LocalProperties.Basic

Goal state before:
pp: P Q : {R S : Type u} → [inst : CommRing R] → [inst_1 : CommRing S] → (R →+* S) → Prop
hP : OfLocalizationSpanTarget fun {R S} [CommRing R] [CommRing S] ↦ P
hQ : OfLocalizationSpanTarget fun {R S} [CommRing R] [CommRing S] ↦ Q
⊢ OfLocalizationSpanTarget fun {R S} [CommRing R] [CommRing S] f ↦ P f ∧ Q f

Tactic:
introv R hs hf
  exact ⟨hP f s hs fun r ↦ (hf r).1, hQ f s hs fun r ↦ (hf r).2⟩

Goal state after:
Module: Mathlib.RingTheory.LocalProperties.Basic

Goal state before:
pp: P Q : {R S : Type u} → [inst : CommRing R] → [inst_1 : CommRing S] → (R →+* S) → Prop
hP : OfLocalizationSpan fun {R S} [CommRing R] [CommRing S] ↦ P
hQ : OfLocalizationSpan fun {R S} [CommRing R] [CommRing S] ↦ Q
⊢ OfLocalizationSpan fun {R S} [CommRing R] [CommRing S] f ↦ P f ∧ Q f

Tactic:
introv R hs hf
  exact ⟨hP f s hs fun r ↦ (hf r).1, hQ f s hs fun r ↦ (hf r).2⟩

Goal state after:
Module: Mathlib.LinearAlgebra.Matrix.Polynomial

Goal state before:
pp: n : Type u_1
α : Type u_2
inst✝² : DecidableEq n
inst✝¹ : Fintype n
inst✝ : CommRing α
A B : Matrix n n α
g : Equiv.Perm n
⊢ (sign g • ∏ i, (X • A.map ⇑C + B.map ⇑C) (g i) i).natDegree ≤ Fintype.card n

Tactic:
calc
    natDegree (sign g • ∏ i : n, (X • A.map C + B.map C : Matrix n n α[X]) (g i) i) ≤
        natDegree (∏ i : n, (X • A.map C + B.map C : Matrix n n α[X]) (g i) i) := by
      rcases Int.units_eq_one_or (sign g) with sg | sg
      · rw [sg, one_smul]
      · rw [sg, Units.neg_smul, one_smul, natDegree_neg]
    _ ≤ ∑ i : n, natDegree (((X : α[X]) • A.map C + B.map C : Matrix n n α[X]) (g i) i) :=
      (natDegree_prod_le (Finset.univ : Finset n) fun i : n =>
        (X • A.map C + B.map C : Matrix n n α[X]) (g i) i)
    _ ≤ Finset.univ.card • 1 := (Finset.sum_le_card_nsmul _ _ 1 fun (i : n) _ => ?_)
    _ ≤ Fintype.card n := by simp [mul_one, Finset.card_univ]

Goal state after:
n : Type u_1
α : Type u_2
inst✝² : DecidableEq n
inst✝¹ : Fintype n
inst✝ : CommRing α
A B : Matrix n n α
g : Equiv.Perm n
i : n
x✝ : i ∈ Finset.univ
⊢ ((X • A.map ⇑C + B.map ⇑C) (g i) i).natDegree ≤ 1
Module: Mathlib.Algebra.Polynomial.Laurent

Goal state before:
pp: case insert
R : Type u_1
inst✝ : Semiring R
M : R[T;T⁻¹] → Prop
p : R[T;T⁻¹]
h_C : ∀ (a : R), M (C a)
h_add : ∀ {p q : R[T;T⁻¹]}, M p → M q → M (p + q)
h_C_mul_T : ∀ (n : ℕ) (a : R), M (C a * T ↑n) → M (C a * T (↑n + 1))
h_C_mul_T_Z : ∀ (n : ℕ) (a : R), M (C a * T (-↑n)) → M (C a * T (-↑n - 1))
A : ∀ {n : ℤ} {a : R}, M (C a * T n)
⊢ ∀ (a : ℤ) (s : Finset ℤ), a ∉ s → M (∑ n ∈ s, C (p.coeff n) * T n) → M (∑ n ∈ insert a s, C (p.coeff n) * T n)

Tactic:
· intro n s ns ih
      rw [Finset.sum_insert ns]
      exact h_add A ih

Goal state after:
Module: Mathlib.Algebra.Polynomial.Laurent

Goal state before:
pp: R : Type u_1
inst✝¹ : Semiring R
inst✝ : DecidableEq R
n : ℤ
a : R
⊢ (C a * T n).degree = if a = 0 then ⊥ else ↑n

Tactic:
split_ifs with h <;>
    simp only [h, map_zero, zero_mul, degree_zero, degree_C_mul_T, Ne,
      not_false_iff]

Goal state after:
Module: Mathlib.LinearAlgebra.Matrix.Adjugate

Goal state before:
pp: case inr
n : Type v
α : Type w
inst✝² : DecidableEq n
inst✝¹ : Fintype n
inst✝ : CommRing α
v : n → α
i j : n
hij : i ≠ j
⊢ ((diagonal v).updateCol j (Pi.single i 1)).det = 0

Tactic:
refine det_eq_zero_of_row_eq_zero j fun k => ?_

Goal state after:
case inr
n : Type v
α : Type w
inst✝² : DecidableEq n
inst✝¹ : Fintype n
inst✝ : CommRing α
v : n → α
i j : n
hij : i ≠ j
k : n
⊢ (diagonal v).updateCol j (Pi.single i 1) j k = 0
Module: Mathlib.Algebra.Polynomial.Laurent

Goal state before:
pp: case pos
R : Type u_1
inst✝¹ : CommSemiring R
S : Type u_3
inst✝ : CommSemiring S
f : R →+* S
x : Sˣ
n : ℤ
hn : 0 ≤ n
⊢ (eval₂ f x) (T n) = ↑(x ^ n)

Tactic:
lift n to ℕ using hn
    apply eval₂_T_n

Goal state after:
Module: Mathlib.LinearAlgebra.Matrix.Adjugate

Goal state before:
pp: case mk
n : Type v
α : Type w
inst✝² : DecidableEq n
inst✝¹ : Fintype n
inst✝ : CommRing α
A : Matrix n n α
i : n
this : Nonempty n
n' : ℕ
hn' : Fintype.card n = n'.succ
x✝ : Trunc (n ≃ Fin n'.succ)
e : n ≃ Fin n'.succ
A' : Matrix (Fin n'.succ) (Fin n'.succ) α := (reindex e e) A
⊢ ∑ j, (-1) ^ (↑(e i) + ↑j) * A' (e i) j * (A'.submatrix (e i).succAbove j.succAbove).det =
    ∑ j, A' (e i) j * A'.adjugate j (e i)

Tactic:
mul_assoc,

Goal state after:
case mk
n : Type v
α : Type w
inst✝² : DecidableEq n
inst✝¹ : Fintype n
inst✝ : CommRing α
A : Matrix n n α
i : n
this : Nonempty n
n' : ℕ
hn' : Fintype.card n = n'.succ
x✝ : Trunc (n ≃ Fin n'.succ)
e : n ≃ Fin n'.succ
A' : Matrix (Fin n'.succ) (Fin n'.succ) α := (reindex e e) A
⊢ ∑ x, (-1) ^ (↑(e i) + ↑x) * (A' (e i) x * (A'.submatrix (e i).succAbove x.succAbove).det) =
    ∑ j, A' (e i) j * A'.adjugate j (e i)
Module: Mathlib.LinearAlgebra.Matrix.NonsingularInverse

Goal state before:
pp: l : Type u_1
m : Type u
n : Type u'
α : Type v
inst✝³ : Fintype n
inst✝² : DecidableEq n
inst✝¹ : CommRing α
A B : Matrix n n α
v : n → α
inst✝ : Invertible (diagonal v)
i : n
this : Invertible (diagonal v).det := (diagonal v).detInvertibleOfInvertible
⊢ (⅟(diagonal v).det * ∏ j ∈ univ.erase i, v j) * v i = 1

Tactic:
mul_assoc,

Goal state after:
l : Type u_1
m : Type u
n : Type u'
α : Type v
inst✝³ : Fintype n
inst✝² : DecidableEq n
inst✝¹ : CommRing α
A B : Matrix n n α
v : n → α
inst✝ : Invertible (diagonal v)
i : n
this : Invertible (diagonal v).det := (diagonal v).detInvertibleOfInvertible
⊢ ⅟(diagonal v).det * ((∏ j ∈ univ.erase i, v j) * v i) = 1
Module: Mathlib.LinearAlgebra.Matrix.NonsingularInverse

Goal state before:
pp: n : Type u'
α : Type v
inst✝² : Fintype n
inst✝¹ : DecidableEq n
inst✝ : CommRing α
A : Matrix n n α
b : n → α
h : IsUnit A.det
⊢ A.det • Aᵀ⁻¹ *ᵥ b = Aᵀ.cramer b

Tactic:
← det_transpose,

Goal state after:
n : Type u'
α : Type v
inst✝² : Fintype n
inst✝¹ : DecidableEq n
inst✝ : CommRing α
A : Matrix n n α
b : n → α
h : IsUnit A.det
⊢ Aᵀ.det • Aᵀ⁻¹ *ᵥ b = Aᵀ.cramer b
Module: Mathlib.RingTheory.MatrixPolynomialAlgebra

Goal state before:
pp: case hC
R : Type u_1
inst✝² : CommSemiring R
n : Type w
inst✝¹ : DecidableEq n
inst✝ : Fintype n
M✝ : (Matrix n n R)[X]
r : R
M : Matrix n n R
⊢ (((aeval r).mapMatrix.comp ↑matPolyEquiv.symm).comp CAlgHom) M =
    ((eval₂AlgHom (AlgHom.id R (Matrix n n R)) ((scalar n) r) ⋯).comp CAlgHom) M

Tactic:
simp [Function.comp_def]

Goal state after:
Module: Mathlib.RingTheory.MatrixPolynomialAlgebra

Goal state before:
pp: R : Type u_1
inst✝² : CommSemiring R
n : Type w
inst✝¹ : DecidableEq n
inst✝ : Fintype n
m : Matrix n n R[X]
i j : n
k : ℕ
⊢ (matPolyEquiv m).coeff k = 0 → (m i j).coeff k = 0

Tactic:
intro hk

Goal state after:
R : Type u_1
inst✝² : CommSemiring R
n : Type w
inst✝¹ : DecidableEq n
inst✝ : Fintype n
m : Matrix n n R[X]
i j : n
k : ℕ
hk : (matPolyEquiv m).coeff k = 0
⊢ (m i j).coeff k = 0
Module: Mathlib.RingTheory.MatrixAlgebra

Goal state before:
pp: m : Type u_2
n : Type u_3
R : Type u_5
S : Type u_6
A : Type u_7
B : Type u_8
inst✝¹² : CommSemiring R
inst✝¹¹ : Semiring S
inst✝¹⁰ : Semiring A
inst✝⁹ : Semiring B
inst✝⁸ : Algebra R S
inst✝⁷ : Algebra R A
inst✝⁶ : Algebra R B
inst✝⁵ : Fintype m
inst✝⁴ : Fintype n
inst✝³ : DecidableEq m
inst✝² : DecidableEq n
inst✝¹ : Module S A
inst✝ : IsScalarTower R S A
⊢ (kroneckerTMulLinearEquiv m m n n R S A B) 1 = 1

Tactic:
by simp [Algebra.TensorProduct.one_def]

Goal state after:
Module: Mathlib.LinearAlgebra.Matrix.SchurComplement

Goal state before:
pp: l : Type u_1
m : Type u_2
n : Type u_3
α : Type u_4
inst✝⁷ : Fintype l
inst✝⁶ : Fintype m
inst✝⁵ : Fintype n
inst✝⁴ : DecidableEq l
inst✝³ : DecidableEq m
inst✝² : DecidableEq n
inst✝¹ : CommRing α
A : Matrix m m α
C : Matrix n m α
D : Matrix n n α
inst✝ : Invertible (fromBlocks A 0 C D)
⊢ (⅟(fromBlocks A 0 C D)).toBlocks₂₂ * D = 1

Tactic:
have := invOf_mul_self (fromBlocks A 0 C D)

Goal state after:
l : Type u_1
m : Type u_2
n : Type u_3
α : Type u_4
inst✝⁷ : Fintype l
inst✝⁶ : Fintype m
inst✝⁵ : Fintype n
inst✝⁴ : DecidableEq l
inst✝³ : DecidableEq m
inst✝² : DecidableEq n
inst✝¹ : CommRing α
A : Matrix m m α
C : Matrix n m α
D : Matrix n n α
inst✝ : Invertible (fromBlocks A 0 C D)
this : ⅟(fromBlocks A 0 C D) * fromBlocks A 0 C D = 1
⊢ (⅟(fromBlocks A 0 C D)).toBlocks₂₂ * D = 1
Module: Mathlib.Algebra.Polynomial.Identities

Goal state before:
pp: case e_f
R : Type u
S : Type v
T : Type w
ι : Type x
k : Type y
A : Type z
a b : R
m n : ℕ
inst✝ : CommRing R
f : R[X]
x y : R
i : ℕ
⊢ f.coeff i * x ^ i - f.coeff i * y ^ i = f.coeff i * ↑(powSubPowFactor x y i) * (x - y)

Tactic:
mul_assoc,

Goal state after:
case e_f
R : Type u
S : Type v
T : Type w
ι : Type x
k : Type y
A : Type z
a b : R
m n : ℕ
inst✝ : CommRing R
f : R[X]
x y : R
i : ℕ
⊢ f.coeff i * x ^ i - f.coeff i * y ^ i = f.coeff i * (↑(powSubPowFactor x y i) * (x - y))
Module: Mathlib.RingTheory.Nilpotent.Basic

Goal state before:
pp: R : Type u_1
inst✝ : Ring R
r : R
hnil : IsNilpotent r
⊢ IsUnit (1 - r)

Tactic:
rw [← IsUnit.neg_iff, neg_sub]
  exact isUnit_sub_one hnil

Goal state after:
Module: Mathlib.RingTheory.Nilpotent.Basic

Goal state before:
pp: case insert.hx
R : Type u_1
inst✝ : Semiring R
ι : Type u_3
f : ι → R
j : ι
s : Finset ι
hj : j ∉ s
ih : (∀ i ∈ s, IsNilpotent (f i)) → (∀ (i j : ι), i ∈ s → j ∈ s → Commute (f i) (f j)) → IsNilpotent (∑ i ∈ s, f i)
hnp : ∀ i ∈ insert j s, IsNilpotent (f i)
h_comm : ∀ (i j_1 : ι), i ∈ insert j s → j_1 ∈ insert j s → Commute (f i) (f j_1)
⊢ IsNilpotent (f j)

Tactic:
apply hnp; simp

Goal state after:
Module: Mathlib.RingTheory.Nilpotent.Basic

Goal state before:
pp: R : Type u_1
x y : R
inst✝ : Semiring R
h_comm : Commute x y
hy : y ∈ nonZeroDivisorsRight R
k : ℕ
hk : x ^ k * y ^ k = 0
⊢ IsNilpotent x

Tactic:
exact ⟨k, (nonZeroDivisorsRight R).pow_mem hy k _ hk⟩

Goal state after:
Module: Mathlib.RingTheory.Nilpotent.Basic

Goal state before:
pp: R : Type u_1
x y : R
inst✝ : Ring R
h_comm : Commute x (-y)
hx : IsNilpotent x
hy : IsNilpotent y
⊢ IsNilpotent (x - y)

Tactic:
rw [← isNilpotent_neg_iff] at hy

Goal state after:
R : Type u_1
x y : R
inst✝ : Ring R
h_comm : Commute x (-y)
hx : IsNilpotent x
hy : IsNilpotent (-y)
⊢ IsNilpotent (x - y)
Module: Mathlib.RingTheory.Polynomial.Nilpotent

Goal state before:
pp: R : Type u_1
inst✝ : CommRing R
k : ℕ
hind :
  ∀ m < k, ∀ {P : R[X]}, IsUnit (P.coeff 0) → (∀ (i : ℕ), i ≠ 0 → IsNilpotent (P.coeff i)) → P.natDegree = m → IsUnit P
P : R[X]
hunit : IsUnit (P.coeff 0)
hnil : ∀ (i : ℕ), i ≠ 0 → IsNilpotent (P.coeff i)
h : P.natDegree = k
hdeg : ¬P.natDegree = 0
P₁ : R[X] := P.eraseLead
hP₁ : P₁ = P.eraseLead
this : IsUnit P₁
⊢ IsUnit (P.eraseLead + (monomial P.natDegree) P.leadingCoeff)

Tactic:
← C_mul_X_pow_eq_monomial,

Goal state after:
R : Type u_1
inst✝ : CommRing R
k : ℕ
hind :
  ∀ m < k, ∀ {P : R[X]}, IsUnit (P.coeff 0) → (∀ (i : ℕ), i ≠ 0 → IsNilpotent (P.coeff i)) → P.natDegree = m → IsUnit P
P : R[X]
hunit : IsUnit (P.coeff 0)
hnil : ∀ (i : ℕ), i ≠ 0 → IsNilpotent (P.coeff i)
h : P.natDegree = k
hdeg : ¬P.natDegree = 0
P₁ : R[X] := P.eraseLead
hP₁ : P₁ = P.eraseLead
this : IsUnit P₁
⊢ IsUnit (P.eraseLead + C P.leadingCoeff * X ^ P.natDegree)
Module: Mathlib.LinearAlgebra.Matrix.Charpoly.LinearMap

Goal state before:
pp: case mp
ι : Type u_1
inst✝⁴ : Fintype ι
M : Type u_2
inst✝³ : AddCommGroup M
R : Type u_3
inst✝² : CommRing R
inst✝¹ : Module R M
b : ι → M
inst✝ : DecidableEq ι
A : Matrix ι ι R
f : Module.End R M
h : Represents b A f
i : ι
⊢ ∑ i_1, A i_1 i • b i_1 = f (b i)

Tactic:
have := LinearMap.congr_fun h (Pi.single i 1)

Goal state after:
case mp
ι : Type u_1
inst✝⁴ : Fintype ι
M : Type u_2
inst✝³ : AddCommGroup M
R : Type u_3
inst✝² : CommRing R
inst✝¹ : Module R M
b : ι → M
inst✝ : DecidableEq ι
A : Matrix ι ι R
f : Module.End R M
h : Represents b A f
i : ι
this : ((PiToModule.fromMatrix R b) A) (Pi.single i 1) = ((PiToModule.fromEnd R b) f) (Pi.single i 1)
⊢ ∑ i_1, A i_1 i • b i_1 = f (b i)
Module: Mathlib.LinearAlgebra.Matrix.Charpoly.LinearMap

Goal state before:
pp: case inr
M : Type u_2
inst✝³ : AddCommGroup M
R : Type u_3
inst✝² : CommRing R
inst✝¹ : Module R M
inst✝ : Module.Finite R M
f : Module.End R M
I : Ideal R
hI : range f ≤ I • ⊤
h✝ : Nontrivial R
s : Finset M
hs_card : s.card = ⊤.spanFinrank
hs_span : Submodule.span R ↑s = ⊤
this : Submodule.span R (Set.range Subtype.val) = ⊤
⊢ ∃ p, p.Monic ∧ p.natDegree = ⊤.spanFinrank ∧ (∀ (k : ℕ), p.coeff k ∈ I ^ (p.natDegree - k)) ∧ (aeval f) p = 0

Tactic:
obtain ⟨A, rfl, h⟩ := Matrix.isRepresentation.toEnd_exists_mem_ideal R ((↑) : s → M) this f I hI

Goal state after:
case inr
M : Type u_2
inst✝³ : AddCommGroup M
R : Type u_3
inst✝² : CommRing R
inst✝¹ : Module R M
inst✝ : Module.Finite R M
I : Ideal R
h✝ : Nontrivial R
s : Finset M
hs_card : s.card = ⊤.spanFinrank
hs_span : Submodule.span R ↑s = ⊤
this : Submodule.span R (Set.range Subtype.val) = ⊤
A : ↥(isRepresentation R Subtype.val)
h : ∀ (i j : ↥s), ↑A i j ∈ I
hI : range ((isRepresentation.toEnd R Subtype.val this) A) ≤ I • ⊤
⊢ ∃ p,
    p.Monic ∧
      p.natDegree = ⊤.spanFinrank ∧
        (∀ (k : ℕ), p.coeff k ∈ I ^ (p.natDegree - k)) ∧ (aeval ((isRepresentation.toEnd R Subtype.val this) A)) p = 0
Module: Mathlib.Algebra.Module.SpanRank

Goal state before:
pp: R : Type u_1
M : Type u
inst✝² : Semiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
p : Submodule R M
⊢ p.generators ⊆ ↑p

Tactic:
← span_generators p

Goal state after:
R : Type u_1
M : Type u
inst✝² : Semiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
p : Submodule R M
⊢ p.generators ⊆ ↑(span R p.generators)
Module: Mathlib.Algebra.Module.SpanRank

Goal state before:
pp: R : Type u_1
S : Type u_2
M : Type u
inst✝⁶ : Semiring R
inst✝⁵ : Semiring S
σ : R →+* S
inst✝⁴ : AddCommMonoid M
inst✝³ : Module R M
L : Type v
inst✝² : AddCommMonoid L
inst✝¹ : Module S L
inst✝ : RingHomSurjective σ
f : M →ₛₗ[σ] L
hf : Function.Injective ⇑f
p : Submodule R M
s : Set M
hs : Cardinal.mk ↑(⇑f '' s) = (map f p).spanRank
e : span S (⇑f '' s) = map f p
⊢ span R s = p

Tactic:
simpa [(map_injective_of_injective hf).eq_iff] using e

Goal state after:
Module: Mathlib.RingTheory.IntegralClosure.IsIntegral.Basic

Goal state before:
pp: R : Type u_1
S : Type u_4
T : Type u_5
inst✝² : CommRing R
inst✝¹ : CommRing S
inst✝ : Ring T
f : R →+* S
g : S →+* T
x : T
p : R[X]
hp : p.Monic
hx : eval₂ (g.comp f) x p = 0
⊢ g.IsIntegralElem x

Tactic:
exact ⟨p.map f, hp.map _, by simpa only [eval₂_eq_eval_map, map_map] using hx⟩

Goal state after:
Module: Mathlib.Algebra.Polynomial.Eval.Subring

Goal state before:
pp: case mpr
R : Type u
S : Type v
inst✝¹ : Semiring R
inst✝ : Semiring S
f : R →+* S
p : S[X]
h : ∀ (n : ℕ), p.coeff n ∈ f.rangeS
i : ℕ
⊢ i ∈ Finset.range (p.natDegree + 1) → C (p.coeff i) * X ^ i ∈ (mapRingHom f).rangeS

Tactic:
_hi

Goal state after:
case mpr
R : Type u
S : Type v
inst✝¹ : Semiring R
inst✝ : Semiring S
f : R →+* S
p : S[X]
h : ∀ (n : ℕ), p.coeff n ∈ f.rangeS
i : ℕ
_hi : i ∈ Finset.range (p.natDegree + 1)
⊢ C (p.coeff i) * X ^ i ∈ (mapRingHom f).rangeS
Module: Mathlib.RingTheory.IntegralClosure.IsIntegral.Basic

Goal state before:
pp: R : Type u_1
A : Type u_2
B : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Ring B
inst✝³ : Algebra R A
inst✝² : Algebra R B
inst✝¹ : Algebra A B
inst✝ : IsScalarTower R A B
x : A
h : IsIntegral R x
⊢ IsIntegral R ((algebraMap A B) x)

Tactic:
rcases h with ⟨f, hf, hx⟩

Goal state after:
R : Type u_1
A : Type u_2
B : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Ring B
inst✝³ : Algebra R A
inst✝² : Algebra R B
inst✝¹ : Algebra A B
inst✝ : IsScalarTower R A B
x : A
f : R[X]
hf : f.Monic
hx : eval₂ (algebraMap R A) x f = 0
⊢ IsIntegral R ((algebraMap A B) x)
Module: Mathlib.RingTheory.IntegralClosure.Algebra.Basic

Goal state before:
pp: R : Type u_1
A : Type u_2
inst✝⁸ : CommRing R
inst✝⁷ : CommRing A
inst✝⁶ : Algebra R A
inst✝⁵ : IsDomain A
M : Type u_5
inst✝⁴ : AddCommGroup M
inst✝³ : Module R M
inst✝² : Module A M
inst✝¹ : IsScalarTower R A M
inst✝ : Module.IsTorsionFree A M
N : Submodule R M
hN : N ≠ ⊥
hN' : N.FG
x : A
hx : ∀ n ∈ N, x • n ∈ N
A' : Subalgebra R A := ⋯
r : R
s : ↥A'
x✝ : ↥N
⊢ ↑(((DistribSMul.toLinearMap R M (r • s)).restrict ⋯) x✝) =
    ↑(((RingHom.id R) r • (DistribSMul.toLinearMap R M s).restrict ⋯) x✝)

Tactic:
apply smul_assoc

Goal state after:
Module: Mathlib.RingTheory.IntegralClosure.Algebra.Basic

Goal state before:
pp: G : Type u_1
R : Type u_2
K : Type u_3
inst✝⁵ : CommRing R
inst✝⁴ : CommRing K
inst✝³ : Algebra R K
inst✝² : Group G
inst✝¹ : MulSemiringAction G K
inst✝ : SMulCommClass G R K
g h : G
x : ↥(integralClosure R K)
⊢ (g * h) • x = g • h • x

Tactic:
by ext; exact mul_smul g h (x : K)

Goal state after:
Module: Mathlib.Algebra.Polynomial.HasseDeriv

Goal state before:
pp: case h₀
R : Type u_1
inst✝ : Semiring R
k : ℕ
f : R[X]
n i : ℕ
⊢ i ∈ f.support → i ≠ n + k → ((monomial (i - k)) (↑(i.choose k) * f.coeff i)).coeff n = 0

Tactic:
_hi

Goal state after:
case h₀
R : Type u_1
inst✝ : Semiring R
k : ℕ
f : R[X]
n i : ℕ
_hi : i ∈ f.support
⊢ i ≠ n + k → ((monomial (i - k)) (↑(i.choose k) * f.coeff i)).coeff n = 0