mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.RingTheory.Ideal.Quotient.Nilpotent

Goal state before:
pp: R : Type u_2
inst✝¹ : CommRing R
S : Type u_2
inst✝ : CommRing S
I : Ideal S
e : I ^ 2 = ⊥
x : S
H : IsUnit ((Ideal.Quotient.mk I) x)
y : S
hy : (Ideal.Quotient.mk I) y = ↑H.unit⁻¹
this✝ : x * y - 1 ∈ I
this : (x * y - 1) ^ 2 = 0
⊢ 1 - x * (y * (2 - x * y)) = 0

Tactic:
← this

Goal state after:
R : Type u_2
inst✝¹ : CommRing R
S : Type u_2
inst✝ : CommRing S
I : Ideal S
e : I ^ 2 = ⊥
x : S
H : IsUnit ((Ideal.Quotient.mk I) x)
y : S
hy : (Ideal.Quotient.mk I) y = ↑H.unit⁻¹
this✝ : x * y - 1 ∈ I
this : (x * y - 1) ^ 2 = 0
⊢ 1 - x * (y * (2 - x * y)) = (x * y - 1) ^ 2
Module: Mathlib.Algebra.Module.LocalizedModule.Submodule

Goal state before:
pp: R : Type u_1
M : Type u_3
N : Type u_4
inst✝¹⁰ : CommSemiring R
inst✝⁹ : AddCommMonoid M
inst✝⁸ : AddCommMonoid N
inst✝⁷ : Module R M
inst✝⁶ : Module R N
p : Submonoid R
f : M →ₗ[R] N
inst✝⁵ : IsLocalizedModule p f
P : Type u_5
inst✝⁴ : AddCommMonoid P
inst✝³ : Module R P
Q : Type u_6
inst✝² : AddCommMonoid Q
inst✝¹ : Module R Q
f' : P →ₗ[R] Q
inst✝ : IsLocalizedModule p f'
g : M →ₗ[R] P
a : M
b c : ↥p
hc : c • g a = 0
⊢ g (c • a) = 0

Tactic:
simpa

Goal state after:
Module: Mathlib.Algebra.Module.LocalizedModule.Submodule

Goal state before:
pp: R : Type u_1
M : Type u_3
N : Type u_4
inst✝¹⁰ : CommSemiring R
inst✝⁹ : AddCommMonoid M
inst✝⁸ : AddCommMonoid N
inst✝⁷ : Module R M
inst✝⁶ : Module R N
p : Submonoid R
f : M →ₗ[R] N
inst✝⁵ : IsLocalizedModule p f
P : Type u_5
inst✝⁴ : AddCommMonoid P
inst✝³ : Module R P
Q : Type u_6
inst✝² : AddCommMonoid Q
inst✝¹ : Module R Q
f' : P →ₗ[R] Q
inst✝ : IsLocalizedModule p f'
g : M →ₗ[R] P
⊢ ((IsLocalizedModule.map p f f') g).range = localized₀ p f' g.range

Tactic:
by
  ext; simp [mem_localized₀, mem_range, (mk'_surjective p f).exists]

Goal state after:
Module: Mathlib.RingTheory.PolynomialAlgebra

Goal state before:
pp: R : Type u_1
A : Type u_3
inst✝² : CommSemiring R
inst✝¹ : Semiring A
inst✝ : Algebra R A
p q : A[X]
⊢ invFun R A (p + q) = invFun R A p + invFun R A q

Tactic:
simp only [invFun, eval₂_add]

Goal state after:
Module: Mathlib.RingTheory.PolynomialAlgebra

Goal state before:
pp: R : Type u_1
S : Type u_2
A : Type u_3
inst✝⁶ : CommSemiring R
inst✝⁵ : CommSemiring S
inst✝⁴ : Semiring A
inst✝³ : Algebra R A
inst✝² : Algebra R S
inst✝¹ : Algebra S A
inst✝ : IsScalarTower R S A
x✝¹ : R[X]
x✝ : A[X]
n✝ : ℕ
⊢ ∑ p ∈ Finset.antidiagonal n✝, ((mapRingHom (algebraMap R A)) x✝¹).coeff p.swap.1 * x✝.coeff p.swap.2 =
    ∑ x ∈ Finset.antidiagonal n✝, x✝.coeff x.1 * ((mapRingHom (algebraMap R A)) x✝¹).coeff x.2

Tactic:
simp [Algebra.commutes]

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

Goal state before:
pp: 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, x * (algebraMap R T) ↑y.2 = (algebraMap R T) y.1

Tactic:
rcases IsLocalization.surj N x with ⟨⟨y, s⟩, eq₁⟩

Goal state after:
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) ↑(y, s).2 = (algebraMap S T) (y, s).1
⊢ ∃ y, x * (algebraMap R T) ↑y.2 = (algebraMap R T) y.1
Module: Mathlib.RingTheory.Localization.AtPrime.Basic

Goal state before:
pp: R : Type u_1
inst✝⁵ : CommSemiring R
q : Ideal R
inst✝⁴ : q.IsPrime
S : Type u_4
inst✝³ : CommSemiring S
inst✝² : Algebra R S
inst✝¹ : IsLocalization.AtPrime S q
p : Ideal R
inst✝ : p.IsPrime
hpq : p ≤ q
disj : Disjoint ↑q.primeCompl ↑p
⊢ p.IsPrime

Tactic:
simpa

Goal state after:
Module: Mathlib.RingTheory.Localization.AtPrime.Basic

Goal state before:
pp: R : Type u_1
inst✝⁴ : CommSemiring R
M : Submonoid R
S : Type u_4
inst✝³ : CommSemiring S
inst✝² : Algebra R S
inst✝¹ : IsLocalization M S
J : Ideal S
inst✝ : (under R J).IsMaximal
⊢ J ≠ ⊤

Tactic:
rintro rfl
    exact Ideal.IsMaximal.ne_top ‹_› (by simp)

Goal state after:
Module: Mathlib.RingTheory.Localization.AtPrime.Basic

Goal state before:
pp: R : Type u_1
inst✝⁴ : CommSemiring R
M : Submonoid R
S : Type u_4
inst✝³ : CommSemiring S
inst✝² : Algebra R S
inst✝¹ : IsLocalization M S
J : Ideal S
inst✝ : (under R J).IsMaximal
m : Ideal S
maxm : m.IsMaximal
hm : under R J ≤ under R m
⊢ (map (algebraMap R S) (under R m)).IsMaximal

Tactic:
IsLocalization.map_under M S m

Goal state after:
R : Type u_1
inst✝⁴ : CommSemiring R
M : Submonoid R
S : Type u_4
inst✝³ : CommSemiring S
inst✝² : Algebra R S
inst✝¹ : IsLocalization M S
J : Ideal S
inst✝ : (under R J).IsMaximal
m : Ideal S
maxm : m.IsMaximal
hm : under R J ≤ under R m
⊢ m.IsMaximal
Module: Mathlib.RingTheory.TensorProduct.Quotient

Goal state before:
pp: A : Type u_1
B : Type u_2
inst✝² : CommRing A
inst✝¹ : CommRing B
inst✝ : Algebra A B
I : Ideal A
x : A
this :
  (TensorProduct.comm A B (A ⧸ I))
      ((quotIdealMapEquivTensorQuot B I) ((Ideal.Quotient.mk (Ideal.map (algebraMap A B) I)) ((algebraMap A B) x))) =
    (algebraMap A ((A ⧸ I) ⊗[A] B)) x
⊢ ((quotIdealMapEquivTensorQuot B I).toRingEquiv.trans (TensorProduct.comm A B (A ⧸ I)).toRingEquiv).toFun
      ((algebraMap A (B ⧸ Ideal.map (algebraMap A B) I)) x) =
    (algebraMap A ((A ⧸ I) ⊗[A] B)) x

Tactic:
simpa

Goal state after:
Module: Mathlib.RingTheory.EssentialFiniteness

Goal state before:
pp: R : Type u_1
S : Type u_2
T : Type u_3
inst✝⁵ : CommRing R
inst✝⁴ : CommRing S
inst✝³ : CommRing T
inst✝² : Algebra R S
inst✝¹ : Algebra R T
inst✝ : EssFiniteType R S
f g : S →ₐ[R] T
H : ∀ s ∈ finset R S, f s = g s
this : f.toRingHom = g.toRingHom
x✝ : S
⊢ f x✝ = g x✝

Tactic:
exact RingHom.congr_fun this _

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

Goal state before:
pp: P : {R S : Type u} → [inst : CommRing R] → [inst_1 : CommRing S] → (R →+* S) → Prop
hP : StableUnderCompositionWithLocalizationAway fun {R S} [CommRing R] [CommRing S] ↦ P
R S T : Type u
x✝² : CommRing R
x✝¹ : CommRing S
x✝ : CommRing T
f : S →+* T
e : R ≃+* S
hf : P f
this : Algebra R S := e.toRingHom.toAlgebra
⊢ (fun {R S} [CommRing R] [CommRing S] ↦ P) (f.comp e.toRingHom)

Tactic:
have : IsLocalization.Away (1 : R) S :=
      IsLocalization.away_of_isUnit_of_bijective _ isUnit_one e.bijective

Goal state after:
P : {R S : Type u} → [inst : CommRing R] → [inst_1 : CommRing S] → (R →+* S) → Prop
hP : StableUnderCompositionWithLocalizationAway fun {R S} [CommRing R] [CommRing S] ↦ P
R S T : Type u
x✝² : CommRing R
x✝¹ : CommRing S
x✝ : CommRing T
f : S →+* T
e : R ≃+* S
hf : P f
this✝ : Algebra R S := e.toRingHom.toAlgebra
this : IsLocalization.Away 1 S
⊢ (fun {R S} [CommRing R] [CommRing S] ↦ P) (f.comp e.toRingHom)
Module: Mathlib.RingTheory.LocalProperties.Basic

Goal state before:
pp: P : {R S : Type u} → [inst : CommRing R] → [inst_1 : CommRing S] → (R →+* S) → Prop
hP : OfLocalizationSpan fun {R S} [CommRing R] [CommRing S] ↦ P
hPi : RespectsIso fun {R S} [CommRing R] [CommRing S] ↦ P
R S : Type u
inst✝¹ : CommRing R
inst✝ : CommRing S
f : R →+* S
s : Set R
hs : Ideal.span s = ⊤
hT :
  ∀ (r : ↑s),
    ∃ Rᵣ Sᵣ x x_1 x_2 x_3,
      ∃ (_ : IsLocalization.Away (↑r) Rᵣ) (_ : IsLocalization.Away (f ↑r) Sᵣ),
        ∃ fᵣ, ∃ (_ : fᵣ.comp (algebraMap R Rᵣ) = (algebraMap S Sᵣ).comp f), P fᵣ
r : ↑s
Rᵣ Sᵣ : Type u
w✝⁵ : CommRing Rᵣ
w✝⁴ : CommRing Sᵣ
w✝³ : Algebra R Rᵣ
w✝² : Algebra S Sᵣ
w✝¹ : IsLocalization.Away (↑r) Rᵣ
w✝ : IsLocalization.Away (f ↑r) Sᵣ
fᵣ : Rᵣ →+* Sᵣ
hfᵣ : fᵣ.comp (algebraMap R Rᵣ) = (algebraMap S Sᵣ).comp f
hf : P fᵣ
e₁ : Localization (Submonoid.powers ↑r) ≃+* Rᵣ := (Localization.algEquiv (Submonoid.powers ↑r) Rᵣ).toRingEquiv
e₂ : Sᵣ ≃+* Localization (Submonoid.powers (f ↑r)) :=
  (IsLocalization.algEquiv (Submonoid.powers (f ↑r)) (Localization (Submonoid.powers (f ↑r))) Sᵣ).symm.toRingEquiv
this : Localization.awayMap f ↑r = (e₂.toRingHom.comp fᵣ).comp e₁.toRingHom
⊢ P ((e₂.toRingHom.comp fᵣ).comp e₁.toRingHom)

Tactic:
apply hPi.right

Goal state after:
P : {R S : Type u} → [inst : CommRing R] → [inst_1 : CommRing S] → (R →+* S) → Prop
hP : OfLocalizationSpan fun {R S} [CommRing R] [CommRing S] ↦ P
hPi : RespectsIso fun {R S} [CommRing R] [CommRing S] ↦ P
R S : Type u
inst✝¹ : CommRing R
inst✝ : CommRing S
f : R →+* S
s : Set R
hs : Ideal.span s = ⊤
hT :
  ∀ (r : ↑s),
    ∃ Rᵣ Sᵣ x x_1 x_2 x_3,
      ∃ (_ : IsLocalization.Away (↑r) Rᵣ) (_ : IsLocalization.Away (f ↑r) Sᵣ),
        ∃ fᵣ, ∃ (_ : fᵣ.comp (algebraMap R Rᵣ) = (algebraMap S Sᵣ).comp f), P fᵣ
r : ↑s
Rᵣ Sᵣ : Type u
w✝⁵ : CommRing Rᵣ
w✝⁴ : CommRing Sᵣ
w✝³ : Algebra R Rᵣ
w✝² : Algebra S Sᵣ
w✝¹ : IsLocalization.Away (↑r) Rᵣ
w✝ : IsLocalization.Away (f ↑r) Sᵣ
fᵣ : Rᵣ →+* Sᵣ
hfᵣ : fᵣ.comp (algebraMap R Rᵣ) = (algebraMap S Sᵣ).comp f
hf : P fᵣ
e₁ : Localization (Submonoid.powers ↑r) ≃+* Rᵣ := ⋯
e₂ : Sᵣ ≃+* Localization (Submonoid.powers (f ↑r)) := ⋯
this : Localization.awayMap f ↑r = (e₂.toRingHom.comp fᵣ).comp e₁.toRingHom
⊢ P (e₂.toRingHom.comp fᵣ)
Module: Mathlib.Algebra.Polynomial.Laurent

Goal state before:
pp: R : Type u_1
inst✝ : Semiring R
motive : R[T;T⁻¹] → Prop
p : R[T;T⁻¹]
add : ∀ (p q : R[T;T⁻¹]), motive p → motive q → motive (p + q)
C_mul_T : ∀ (n : ℤ) (a : R), motive (C a * T n)
⊢ motive p

Tactic:
refine p.induction_on (fun a => ?_) (fun {p q} => add p q) ?_ ?_ <;>
      try exact fun n f _ => C_mul_T _ f

Goal state after:
case refine_1
R : Type u_1
inst✝ : Semiring R
motive : R[T;T⁻¹] → Prop
p : R[T;T⁻¹]
add : ∀ (p q : R[T;T⁻¹]), motive p → motive q → motive (p + q)
C_mul_T : ∀ (n : ℤ) (a : R), motive (C a * T n)
a : R
⊢ motive (C a)
Module: Mathlib.Algebra.Polynomial.Laurent

Goal state before:
pp: case refine_1
R : Type u_1
inst✝ : Semiring R
f✝ f g : R[X]
hf : trunc (toLaurent f) = f
hg : trunc (toLaurent g) = g
⊢ trunc (toLaurent (f + g)) = f + g

Tactic:
simp only [hf, hg, map_add]

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

Goal state before:
pp: case mul_T.succ.convert_2
R : Type u_1
inst✝ : Semiring R
Q : R[T;T⁻¹] → Prop
Qf : ∀ (f : R[X]), Q (toLaurent f)
QT : ∀ (f : R[T;T⁻¹]), Q (f * T 1) → Q f
f : R[X]
n : ℕ
hn : Q (toLaurent f * T (-↑n))
⊢ Q (toLaurent f * T (-↑(n + 1)) * T 1)

Tactic:
simpa

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

Goal state before:
pp: R : Type u_1
inst✝ : Semiring R
n : ℤ
a : R
⊢ (C a * T n).degree ≤ ↑n

Tactic:
by_cases a0 : a = 0

Goal state after:
case pos
R : Type u_1
inst✝ : Semiring R
n : ℤ
a : R
a0 : a = 0
⊢ (C a * T n).degree ≤ ↑n

case neg
R : Type u_1
inst✝ : Semiring R
n : ℤ
a : R
a0 : ¬a = 0
⊢ (C a * T n).degree ≤ ↑n
Module: Mathlib.LinearAlgebra.Dimension.Localization

Goal state before:
pp: R : Type u_1
inst✝¹ : Ring R
inst✝ : IsDomain R
r : R
s : ↥R⁰
h : ∀ (r' : R) (s' : ↥R⁰), ↑s' * r ≠ r' * ↑s
n : ℕ
IH : ∀ (g : ℕ → R) (x : ℕ), ∑ i ∈ Finset.range n, g i • (r * ↑s ^ (i + x)) = 0 → ∀ i < n, g i = 0
g : ℕ → R
x i : ℕ
hin : i < n + 1
hg0 : ¬g 0 = 0
hg : (-∑ i ∈ Finset.range n, g (i + 1) * r * ↑s ^ i) * ↑s * ↑s ^ x = g 0 * r * ↑s ^ x
this : (-∑ i ∈ Finset.range n, g (i + 1) * r * ↑s ^ i) * ↑s = g 0 * r
⊢ g 0 ≠ 0

Tactic:
simpa

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

Goal state before:
pp: m : Type u_1
n : Type u_2
α : Type u_3
inst✝⁷ : Fintype n
inst✝⁶ : DecidableEq n
inst✝⁵ : Fintype m
inst✝⁴ : DecidableEq m
inst✝³ : Ring α
A : Matrix n n α
U : Matrix n m α
C : Matrix m m α
V : Matrix m n α
inst✝² : Invertible A
inst✝¹ : Invertible C
inst✝ : Invertible (⅟C + V * ⅟A * U)
⊢ 1 + ⅟A * U * C * V - ⅟A * U * ⅟(⅟C + V * ⅟A * U) * (⅟C + V * ⅟A * U) * C * V = 1

Tactic:
rw [Matrix.invOf_mul_cancel_right]

Goal state after:
m : Type u_1
n : Type u_2
α : Type u_3
inst✝⁷ : Fintype n
inst✝⁶ : DecidableEq n
inst✝⁵ : Fintype m
inst✝⁴ : DecidableEq m
inst✝³ : Ring α
A : Matrix n n α
U : Matrix n m α
C : Matrix m m α
V : Matrix m n α
inst✝² : Invertible A
inst✝¹ : Invertible C
inst✝ : Invertible (⅟C + V * ⅟A * U)
⊢ 1 + ⅟A * U * C * V - ⅟A * U * C * V = 1
Module: Mathlib.LinearAlgebra.Matrix.NonsingularInverse

Goal state before:
pp: m : Type u
inst✝² : DecidableEq m
K : Type u_3
inst✝¹ : Field K
inst✝ : Fintype m
A : Matrix m m K
⊢ Function.Injective A.mulVec ↔ IsUnit A

Tactic:
rw [← isUnit_transpose, ← vecMul_injective_iff_isUnit]
  simp_rw [vecMul_transpose]

Goal state after:
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 B C : Matrix n n α
h : B * A = 1
g : C * A = 1
⊢ B = C

Tactic:
rw [← inv_eq_left_inv h, ← inv_eq_left_inv g]

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

Goal state before:
pp: α : Type u_1
R : Type v
inst✝⁴ : CommRing R
inst✝³ : LinearOrder α
m : Type u_3
M : Matrix m m R
b : m → α
inst✝² : DecidableEq m
inst✝¹ : Fintype m
inst✝ : Invertible M
hM : M.BlockTriangular b
ih :
  ∀ t ⊂ image b univ,
    ∀ {m : Type u_3} {M : Matrix m m R} {b : m → α} [inst : DecidableEq m] [inst_1 : Fintype m] [Invertible M],
      M.BlockTriangular b → image b univ = t → M⁻¹.BlockTriangular b
i j : m
hij : b j < b i
this✝ : Inhabited m
k : α := (image b univ).max' ⋯
b' : { a // b a < k } → α := fun i ↦ b ↑i
A : Matrix { a // b a < k } { a // b a < k } R := M.toBlock (fun i ↦ b i < k) fun j ↦ b j < k
hi : b i < (image b univ).max' ⋯
this : Invertible A
hA : A.BlockTriangular b'
⊢ image b' univ ⊂ image b univ

Tactic:
convert! image_subtype_univ_ssubset_image_univ k b _ (fun a => a < k) (lt_irrefl _)

Goal state after:
α : Type u_1
R : Type v
inst✝⁴ : CommRing R
inst✝³ : LinearOrder α
m : Type u_3
M : Matrix m m R
b : m → α
inst✝² : DecidableEq m
inst✝¹ : Fintype m
inst✝ : Invertible M
hM : M.BlockTriangular b
ih :
  ∀ t ⊂ image b univ,
    ∀ {m : Type u_3} {M : Matrix m m R} {b : m → α} [inst : DecidableEq m] [inst_1 : Fintype m] [Invertible M],
      M.BlockTriangular b → image b univ = t → M⁻¹.BlockTriangular b
i j : m
hij : b j < b i
this✝ : Inhabited m
k : α := (image b univ).max' ⋯
b' : { a // b a < k } → α := fun i ↦ b ↑i
A : Matrix { a // b a < k } { a // b a < k } R := M.toBlock (fun i ↦ b i < k) fun j ↦ b j < k
hi : b i < (image b univ).max' ⋯
this : Invertible A
hA : A.BlockTriangular b'
⊢ k ∈ image b univ
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
B : Matrix m n α
C : Matrix l m α
D : Matrix l n α
inst✝ : Invertible A
⊢ fromBlocks A B C D = fromBlocks 1 0 (C * ⅟A) 1 * fromBlocks A 0 0 (D - C * ⅟A * B) * fromBlocks 1 (⅟A * B) 0 1

Tactic:
simp only [fromBlocks_multiply, Matrix.mul_zero, Matrix.zero_mul, add_zero, zero_add,
    Matrix.one_mul, Matrix.mul_one, invOf_mul_self, Matrix.mul_invOf_cancel_left,
    Matrix.mul_assoc, add_sub_cancel]

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

Goal state before:
pp: case nil.nil
n : Type u_1
𝕜 : Type u_3
inst✝² : Field 𝕜
inst✝¹ : DecidableEq n
inst✝ : Fintype n
P : Matrix n n 𝕜 → Prop
M : Matrix n n 𝕜
hdiag : ∀ (D : n → 𝕜), (diagonal D).det = M.det → P (diagonal D)
htransvec : ∀ (t : TransvectionStruct n 𝕜), P t.toMatrix
hmul : ∀ (A B : Matrix n n 𝕜), P A → P B → P (A * B)
L L' : List (TransvectionStruct n 𝕜)
D : n → 𝕜
h : M = (List.map toMatrix L).prod * diagonal D * (List.map toMatrix L').prod
PD : P (diagonal D)
E : Matrix n n 𝕜
PE : P E
⊢ P (E * (List.map toMatrix []).prod)

Tactic:
simpa

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

Goal state before:
pp: m : Type u_2
n : Type u_3
α : Type u_4
inst✝⁴ : Fintype m
inst✝³ : Fintype n
inst✝² : DecidableEq m
inst✝¹ : DecidableEq n
inst✝ : CommRing α
A : Matrix m m α
B : Matrix m n α
D : Matrix n n α
hAD : IsUnit A ↔ IsUnit D
⊢ (fromBlocks A B 0 D)⁻¹ = fromBlocks A⁻¹ (-(A⁻¹ * B * D⁻¹)) 0 D⁻¹

Tactic:
by_cases hA : IsUnit A
  · have hD := hAD.mp hA
    cases hA.nonempty_invertible
    cases hD.nonempty_invertible
    let := fromBlocksZero₂₁Invertible A B D
    simp_rw [← invOf_eq_nonsing_inv, invOf_fromBlocks_zero₂₁_eq]
  · have hD := hAD.not.mp hA
    have : ¬IsUnit (fromBlocks A B 0 D) :=
      isUnit_fromBlocks_zero₂₁.not.mpr (not_and'.mpr fun _ => hA)
    simp_rw [nonsing_inv_eq_ringInverse, Ring.inverse_non_unit _ hA, Ring.inverse_non_unit _ hD,
      Ring.inverse_non_unit _ this, Matrix.zero_mul, neg_zero, fromBlocks_zero]

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

Goal state before:
pp: m : Type u_2
n : Type u_3
α : Type u_4
inst✝⁴ : Fintype m
inst✝³ : Fintype n
inst✝² : DecidableEq m
inst✝¹ : DecidableEq n
inst✝ : CommRing α
A : Matrix m n α
B : Matrix n m α
⊢ (1 + B * A).det = (B * A + 1).det

Tactic:
add_comm

Goal state after:
m : Type u_2
n : Type u_3
α : Type u_4
inst✝⁴ : Fintype m
inst✝³ : Fintype n
inst✝² : DecidableEq m
inst✝¹ : DecidableEq n
inst✝ : CommRing α
A : Matrix m n α
B : Matrix n m α
⊢ (B * A + 1).det = (B * A + 1).det
Module: Mathlib.RingTheory.Nilpotent.Basic

Goal state before:
pp: case zero
R : Type u_1
inst✝ : MonoidWithZero R
e : R
idem : IsIdempotentElem e
hn : e ^ 0 = 0
⊢ e = 0

Tactic:
rw [pow_zero] at hn

Goal state after:
case zero
R : Type u_1
inst✝ : MonoidWithZero R
e : R
idem : IsIdempotentElem e
hn : 1 = 0
⊢ e = 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
h2 : ⨅ s, ⨅ (_ : span R s = p), s.encard ≠ ⊤
s : Set M
h : span R s = p
hs : s.Finite
⊢ span R ↑hs.toFinset = p

Tactic:
simpa

Goal state after:
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
s : Set M
hs₁ : s.Finite
hs₂ : span R s = p
⊢ #↑↑⟨s, hs₂⟩ < ℵ₀

Tactic:
simpa

Goal state after:
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
hp : p.FG
n : ℕ
⊢ p.spanRank < ℵ₀

Tactic:
simpa

Goal state after:
Module: Mathlib.LinearAlgebra.Matrix.Charpoly.Coeff

Goal state before:
pp: R : Type u
inst✝² : CommRing R
n : Type v
inst✝¹ : DecidableEq n
inst✝ : Fintype n
M : Matrix n n R
⊢ (↑↑(Equiv.Perm.sign (Equiv.refl n)) * ∏ i, M.charmatrix ((Equiv.refl n) i) i +
          ∑ x ∈ univ.erase (Equiv.refl n), ↑↑(Equiv.Perm.sign x) * ∏ i, M.charmatrix (x i) i -
        ∏ i, (X - C (M i i))).degree <
    ↑(Fintype.card n - 1)

Tactic:
add_comm

Goal state after:
R : Type u
inst✝² : CommRing R
n : Type v
inst✝¹ : DecidableEq n
inst✝ : Fintype n
M : Matrix n n R
⊢ (∑ x ∈ univ.erase (Equiv.refl n), ↑↑(Equiv.Perm.sign x) * ∏ i, M.charmatrix (x i) i +
          ↑↑(Equiv.Perm.sign (Equiv.refl n)) * ∏ i, M.charmatrix ((Equiv.refl n) i) i -
        ∏ i, (X - C (M i i))).degree <
    ↑(Fintype.card n - 1)
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
hp : p.FG
⊢ #↑p.generators < ℵ₀

Tactic:
Submodule.generators_card

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
hp : p.FG
⊢ p.spanRank < ℵ₀
Module: Mathlib.RingTheory.IntegralClosure.IsIntegral.Basic

Goal state before:
pp: case refine_2
R : Type u_6
A : Type u_7
inst✝² : CommRing R
inst✝¹ : Semiring A
inst✝ : Algebra R A
x : A
f : R[X]
hf : f.Monic
hfx : (aeval x) f = 0
a✝ : Nontrivial A
hf1 : f ≠ 1
r : A
hr : r ∈ R[x]
⊢ r ∈ span R ↑(Finset.image (fun x_1 ↦ x ^ x_1) (Finset.range f.natDegree))

Tactic:
Algebra.adjoin_singleton_eq_range_aeval

Goal state after:
case refine_2
R : Type u_6
A : Type u_7
inst✝² : CommRing R
inst✝¹ : Semiring A
inst✝ : Algebra R A
x : A
f : R[X]
hf : f.Monic
hfx : (aeval x) f = 0
a✝ : Nontrivial A
hf1 : f ≠ 1
r : A
hr : r ∈ (aeval x).range
⊢ r ∈ span R ↑(Finset.image (fun x_1 ↦ x ^ x_1) (Finset.range f.natDegree))
Module: Mathlib.Algebra.Module.SpanRank

Goal state before:
pp: R : Type u_1
M : Type u_2
inst✝³ : Semiring R
inst✝² : AddCommMonoid M
inst✝¹ : Module R M
inst✝ : StrongRankCondition R
ι : { s // LinearIndepOn R id s }
s : { s // span R s = ⊤ }
this : #↑↑ι ≤ #↑↑s
⊢ #↑↑ι ≤ #↑↑s

Tactic:
simpa

Goal state after:
Module: Mathlib.LinearAlgebra.Matrix.Charpoly.Coeff

Goal state before:
pp: case e'_3
R : Type u
inst✝² : CommRing R
n : Type v
inst✝¹ : DecidableEq n
inst✝ : Fintype n
M : Matrix n n R
e : Matrix n n R ≃ₗ[R] Matrix (Fin (Fintype.card n)) (Fin (Fintype.card n)) R :=
  reindexLinearEquiv R R (Fintype.equivFin n) (Fintype.equivFin n)
⊢ M.trace = (e M).trace

Tactic:
· delta trace
    rw [← (Fintype.equivFin n).symm.sum_comp]
    simp_rw [e, coe_reindexLinearEquiv, reindex_apply, diag_apply, submatrix_apply]

Goal state after:
Module: Mathlib.LinearAlgebra.Matrix.Charpoly.Coeff

Goal state before:
pp: R : Type u
inst✝² : CommRing R
n : Type v
inst✝¹ : DecidableEq n
inst✝ : Fintype n
M : Matrix n n R
⊢ (1 + X • M.map ⇑C).det = 1 + (C ((1 + X • M.map ⇑C).det.coeff 1) + (1 + X • M.map ⇑C).det.divX.divX * X) * X

Tactic:
← coeff_divX,

Goal state after:
R : Type u
inst✝² : CommRing R
n : Type v
inst✝¹ : DecidableEq n
inst✝ : Fintype n
M : Matrix n n R
⊢ (1 + X • M.map ⇑C).det = 1 + (C ((1 + X • M.map ⇑C).det.divX.coeff 0) + (1 + X • M.map ⇑C).det.divX.divX * X) * X
Module: Mathlib.LinearAlgebra.Matrix.Charpoly.Coeff

Goal state before:
pp: R : Type u
inst✝² : CommRing R
n : Type v
inst✝¹ : DecidableEq n
inst✝ : Fintype n
M : Matrix n n R
I : Ideal R
h : ∀ (i j : n), M i j ∈ I
k : ℕ
c : Equiv.Perm n
this : ∑ x, 1 = Fintype.card n
⊢ (∏ i, M.charmatrix (c i) i).coeff k ∈ I ^ (Fintype.card n - k)

Tactic:
← this

Goal state after:
R : Type u
inst✝² : CommRing R
n : Type v
inst✝¹ : DecidableEq n
inst✝ : Fintype n
M : Matrix n n R
I : Ideal R
h : ∀ (i j : n), M i j ∈ I
k : ℕ
c : Equiv.Perm n
this : ∑ x, 1 = Fintype.card n
⊢ (∏ i, M.charmatrix (c i) i).coeff k ∈ I ^ (∑ x, 1 - k)
Module: Mathlib.Algebra.Polynomial.HasseDeriv

Goal state before:
pp: case succ
R : Type u_1
inst✝ : Semiring R
k✝ k : ℕ
ih : ⇑(k ! • hasseDeriv k) = (⇑derivative)^[k]
⊢ ⇑((k + 1)! • hasseDeriv (k + 1)) = (⇑derivative)^[k + 1]

Tactic:
ext f n : 2

Goal state after:
case succ
R : Type u_1
inst✝ : Semiring R
k✝ k : ℕ
ih : ⇑(k ! • hasseDeriv k) = (⇑derivative)^[k]
f : R[X]
n : ℕ
⊢ (((k + 1)! • hasseDeriv (k + 1)) f).coeff n = ((⇑derivative)^[k + 1] f).coeff n
Module: Mathlib.LinearAlgebra.Matrix.Charpoly.Coeff

Goal state before:
pp: R : Type u
inst✝² : CommRing R
n : Type v
inst✝¹ : DecidableEq n
inst✝ : Fintype n
M : Matrix n n R
k : ℕ
D : (n → R[X]) [⋀^n]→ₗ[R[X]] R[X] := detRowAlternating
⊢ (detRowAlternating (1 + X • M.map ⇑C)).coeff k =
    ∑ x ∈ powersetCard k univ, detRowAlternating (M.submatrix Subtype.val Subtype.val)

Tactic:
add_comm

Goal state after:
R : Type u
inst✝² : CommRing R
n : Type v
inst✝¹ : DecidableEq n
inst✝ : Fintype n
M : Matrix n n R
k : ℕ
D : (n → R[X]) [⋀^n]→ₗ[R[X]] R[X] := detRowAlternating
⊢ (detRowAlternating (X • M.map ⇑C + 1)).coeff k =
    ∑ x ∈ powersetCard k univ, detRowAlternating (M.submatrix Subtype.val Subtype.val)
Module: Mathlib.Algebra.Polynomial.HasseDeriv

Goal state before:
pp: R : Type u_1
inst✝ : Semiring R
k l i : ℕ
hikl : k + l ≤ i
h1 : l ≤ i
h2 : k ≤ i - l
h3 : k ≤ k + l
⊢ i - (k + l) = i - l - k

Tactic:
add_comm

Goal state after:
R : Type u_1
inst✝ : Semiring R
k l i : ℕ
hikl : k + l ≤ i
h1 : l ≤ i
h2 : k ≤ i - l
h3 : k ≤ k + l
⊢ i - (l + k) = i - l - k
Module: Mathlib.RingTheory.Polynomial.ScaleRoots

Goal state before:
pp: case hf
R : Type u_1
A : Type u_3
inst✝² : CommSemiring R
inst✝¹ : Semiring A
inst✝ : Algebra R A
p : R[X]
a : A
r : R
ha : (aeval a) p = 0
⊢ ∀ (s₁ s₂ : R), Commute ((algebraMap R A) s₁) ((algebraMap R A) s₂)

Tactic:
intros; rw [Commute, SemiconjBy, ← map_mul, ← map_mul, mul_comm]

Goal state after: