mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Algebra.Module.Projective

Goal state before:
pp: R : Type u
inst✝¹⁰ : Semiring R
P : Type v
inst✝⁹ : AddCommMonoid P
inst✝⁸ : Module R P
R₀ : Type u_2
M : Type u_1
N : Type u_3
inst✝⁷ : CommSemiring R₀
inst✝⁶ : Algebra R₀ R
inst✝⁵ : AddCommMonoid M
inst✝⁴ : Module R₀ M
inst✝³ : Module R M
inst✝² : IsScalarTower R₀ R M
inst✝¹ : AddCommMonoid N
inst✝ : Module R₀ N
hM : Projective R M
hN : Projective R₀ N
⊢ Projective R (M ⊗[R₀] N)

Tactic:
by
  obtain ⟨sM, hsM⟩ := hM
  obtain ⟨sN, hsN⟩ := hN
  have : Module.Projective R (M ⊗[R₀] (N →₀ R₀)) := by
    fapply Projective.of_split (R := R) (M := ((M →₀ R) ⊗[R₀] (N →₀ R₀)))
    · exact (AlgebraTensorModule.map sM (LinearMap.id (R := R₀) (M := N →₀ R₀)))
    · exact (AlgebraTensorModule.map
        (Finsupp.linearCombination R id) (LinearMap.id (R := R₀) (M := N →₀ R₀)))
    · ext; simp [hsM _]
  fapply Projective.of_split (R := R) (M := (M ⊗[R₀] (N →₀ R₀)))
  · exact (AlgebraTensorModule.map (LinearMap.id (R := R) (M := M)) sN)
  · exact (AlgebraTensorModule.map (LinearMap.id (R := R) (M := M)) (linearCombination R₀ id))
  · ext; simp [hsN _]

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

Goal state before:
pp: n : Type u_3
α : Type v
inst✝² : DecidableEq n
inst✝¹ : Ring α
inst✝ : StarRing α
d : ℤ
⊢ (↑d)ᴴ = ↑d

Tactic:
simp [conjTranspose, Matrix.map_intCast, diagonal_intCast]

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

Goal state before:
pp: l : Type u_1
m : Type u_2
α : Type u_12
inst✝² : DecidableEq l
inst✝¹ : DecidableEq m
inst✝ : Zero α
v : l ⊕ m → α
i j : l
⊢ of (fun i j ↦ diagonal v (Sum.inl i) (Sum.inl j)) i j = diagonal (fun i ↦ v (Sum.inl i)) i j

Tactic:
simp only [Sum.inl.injEq, of_apply, diagonal_apply]

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

Goal state before:
pp: m : Type u_2
n : Type u_3
α : Type v
ι : Type u_6
inst✝² : Mul α
inst✝¹ : AddCommMonoid α
inst✝ : Unique ι
w : m → α
v : n → α
⊢ vecMulVec w v = replicateCol ι w * replicateRow ι v

Tactic:
ext
  simp [vecMulVec, mul_apply]

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

Goal state before:
pp: m : Type u_2
n : Type u_3
α : Type v
β : Type w
M : Matrix m n α
i : m
b : n → α
inst✝ : DecidableEq m
f : α → β
i✝ : m
j✝ : n
⊢ f (M.updateRow i b i✝ j✝) = if i✝ = i then (f ∘ b) j✝ else f (M i✝ j✝)

Tactic:
updateRow_apply

Goal state after:
m : Type u_2
n : Type u_3
α : Type v
β : Type w
M : Matrix m n α
i : m
b : n → α
inst✝ : DecidableEq m
f : α → β
i✝ : m
j✝ : n
⊢ f (if i✝ = i then b j✝ else M i✝ j✝) = if i✝ = i then (f ∘ b) j✝ else f (M i✝ j✝)
Module: Mathlib.LinearAlgebra.Matrix.ToLin

Goal state before:
pp: R : Type u_1
inst✝² : CommSemiring R
m : Type u_4
inst✝¹ : Fintype m
A : Matrix m m R
inst✝ : DecidableEq m
ha : IsUnit A
⊢ LinearIndependent R A.col

Tactic:
rw [← Matrix.mulVec_injective_iff]
  exact Matrix.mulVec_injective_of_isUnit ha

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

Goal state before:
pp: R : Type u_1
inst✝⁷ : CommSemiring R
m : Type u_3
n : Type u_4
inst✝⁶ : Fintype n
inst✝⁵ : DecidableEq n
M₁ : Type u_5
M₂ : Type u_6
inst✝⁴ : AddCommMonoid M₁
inst✝³ : AddCommMonoid M₂
inst✝² : Module R M₁
inst✝¹ : Module R M₂
v₁ : Basis n R M₁
v₂ : Basis m R M₂
inst✝ : Finite m
f : M₁ →ₗ[R] R
x : M₂
⊢ (toMatrix v₁ v₂) (f.smulRight x) = vecMulVec (⇑(v₂.repr x)) (⇑f ∘ ⇑v₁)

Tactic:
by
  ext i j
  simpa [toMatrix_apply, vecMulVec_apply] using mul_comm _ _

Goal state after:
Module: Mathlib.GroupTheory.MonoidLocalization.MonoidWithZero

Goal state before:
pp: M : Type u_1
inst✝² : CommMonoidWithZero M
S : Submonoid M
N : Type u_2
inst✝¹ : CommMonoidWithZero N
f : S.LocalizationMap N
inst✝ : IsCancelMulZero M
n : N
⊢ n ≠ 0 → IsRightRegular n

Tactic:
hn

Goal state after:
M : Type u_1
inst✝² : CommMonoidWithZero M
S : Submonoid M
N : Type u_2
inst✝¹ : CommMonoidWithZero N
f : S.LocalizationMap N
inst✝ : IsCancelMulZero M
n : N
hn : n ≠ 0
⊢ IsRightRegular n
Module: Mathlib.GroupTheory.MonoidLocalization.Divisibility

Goal state before:
pp: M : Type u_1
N : Type u_2
inst✝¹ : CommMonoid M
S : Submonoid M
inst✝ : CommMonoid N
f : S.LocalizationMap N
m : M
h : IsUnit (f m)
s : N
hxs : 1 = f m * s
⊢ ∃ s ∈ S, m ∣ s

Tactic:
have ⟨⟨r, s⟩, hrs⟩ := f.surj s

Goal state after:
M : Type u_1
N : Type u_2
inst✝¹ : CommMonoid M
S : Submonoid M
inst✝ : CommMonoid N
f : S.LocalizationMap N
m : M
h : IsUnit (f m)
s✝ : N
hxs : 1 = f m * s✝
r : M
s : ↥S
hrs : s✝ * f ↑(r, s).2 = f (r, s).1
⊢ ∃ s ∈ S, m ∣ s
Module: Mathlib.RingTheory.OreLocalization.Ring

Goal state before:
pp: case c.c.e_a.e_a
R : Type u_1
inst✝⁴ : Semiring R
S : Submonoid R
inst✝³ : OreSet S
X : Type u_2
inst✝² : AddCommMonoid X
inst✝¹ : Module R X
T : Type u_3
inst✝ : Semiring T
f : R →+* T
fS : ↥S →* Tˣ
hf : ∀ (s : ↥S), f ↑s = ↑(fS s)
r₁ : R
s₁ : ↥S
r₂ : R
s₂ : ↥S
r₃ : R
s₃ : ↥S
h₃ : ↑(s₃ * s₁) = r₃ * ↑s₂
h₃' : s₃ * s₁ = ⟨r₃ * ↑s₂, ⋯⟩
⊢ f r₃ = ↑(fS ⟨r₃ * ↑s₂, ⋯⟩) * ↑(fS s₂)⁻¹

Tactic:
Units.eq_mul_inv_iff_mul_eq,

Goal state after:
case c.c.e_a.e_a
R : Type u_1
inst✝⁴ : Semiring R
S : Submonoid R
inst✝³ : OreSet S
X : Type u_2
inst✝² : AddCommMonoid X
inst✝¹ : Module R X
T : Type u_3
inst✝ : Semiring T
f : R →+* T
fS : ↥S →* Tˣ
hf : ∀ (s : ↥S), f ↑s = ↑(fS s)
r₁ : R
s₁ : ↥S
r₂ : R
s₂ : ↥S
r₃ : R
s₃ : ↥S
h₃ : ↑(s₃ * s₁) = r₃ * ↑s₂
h₃' : s₃ * s₁ = ⟨r₃ * ↑s₂, ⋯⟩
⊢ f r₃ * ↑(fS s₂) = ↑(fS ⟨r₃ * ↑s₂, ⋯⟩)
Module: Mathlib.RingTheory.Adjoin.Basic

Goal state before:
pp: case h
R : Type uR
A : Type uA
B : Type uB
inst✝⁶ : CommSemiring R
inst✝⁵ : CommSemiring A
inst✝⁴ : Algebra R A
inst✝³ : CommSemiring B
inst✝² : Algebra R B
inst✝¹ : Algebra A B
inst✝ : IsScalarTower R A B
r : A
s : Set B
B' : Subalgebra R B
hs : r • s ⊆ ↑B'
hr : (algebraMap A B) r ∈ B'
l : ↑↑(Submonoid.closure s) →₀ R
n₁ : ↥(Submonoid.closure s) → ℕ
n₂ : ∀ (x : ↥(Submonoid.closure s)), r ^ n₁ x • ↑x ∈ Submonoid.closure (r • s)
n : ℕ
⊢ n ≥ l.support.sup n₁ → (r ^ n • l.sum fun i c ↦ c • ↑i) ∈ B'

Tactic:
hn

Goal state after:
case h
R : Type uR
A : Type uA
B : Type uB
inst✝⁶ : CommSemiring R
inst✝⁵ : CommSemiring A
inst✝⁴ : Algebra R A
inst✝³ : CommSemiring B
inst✝² : Algebra R B
inst✝¹ : Algebra A B
inst✝ : IsScalarTower R A B
r : A
s : Set B
B' : Subalgebra R B
hs : r • s ⊆ ↑B'
hr : (algebraMap A B) r ∈ B'
l : ↑↑(Submonoid.closure s) →₀ R
n₁ : ↥(Submonoid.closure s) → ℕ
n₂ : ∀ (x : ↥(Submonoid.closure s)), r ^ n₁ x • ↑x ∈ Submonoid.closure (r • s)
n : ℕ
hn : n ≥ l.support.sup n₁
⊢ (r ^ n • l.sum fun i c ↦ c • ↑i) ∈ B'
Module: Mathlib.RingTheory.Localization.Defs

Goal state before:
pp: R : Type u_1
inst✝⁵ : CommSemiring R
S : Type u_4
inst✝⁴ : CommSemiring S
K : Type u_5
inst✝³ : CommSemiring K
inst✝² : Algebra R K
e : R ≃+* S
inst✝¹ : Algebra S K
M₁ : Submonoid S
M₂ : Submonoid R
hM : Submonoid.map e M₂ = M₁
h : ∀ (x : R), (algebraMap R K) x = (algebraMap S K) (e x)
inst✝ : IsLocalization M₁ K
⊢ IsLocalization M₂ K

Tactic:
rw [IsLocalization.isLocalization_iff_of_base_ringEquiv _ _ e, hM]
  convert! (inferInstance : IsLocalization M₁ K)
  exact Algebra.algebra_ext _ _ (by simp [RingHom.algebraMap_toAlgebra, h])

Goal state after:
Module: Mathlib.Algebra.Algebra.Spectrum.Basic

Goal state before:
pp: R : Type u
A : Type v
inst✝² : CommSemiring R
inst✝¹ : Ring A
inst✝ : Algebra R A
a b : A
r : R
ha : r ∈ resolventSet R a
hb : r ∈ resolventSet R b
⊢ ↑(IsUnit.unit ha)⁻¹ - ↑(IsUnit.unit hb)⁻¹ = ↑(IsUnit.unit ha)⁻¹ * (a - b) * ↑(IsUnit.unit hb)⁻¹

Tactic:
Units.eq_mul_inv_iff_mul_eq,

Goal state after:
R : Type u
A : Type v
inst✝² : CommSemiring R
inst✝¹ : Ring A
inst✝ : Algebra R A
a b : A
r : R
ha : r ∈ resolventSet R a
hb : r ∈ resolventSet R b
⊢ (↑(IsUnit.unit ha)⁻¹ - ↑(IsUnit.unit hb)⁻¹) * ↑(IsUnit.unit hb) = ↑(IsUnit.unit ha)⁻¹ * (a - b)
Module: Mathlib.Algebra.Algebra.Spectrum.Basic

Goal state before:
pp: R : Type u
A : Type v
inst✝² : CommSemiring R
inst✝¹ : Ring A
inst✝ : Algebra R A
a b : A
r : R
⊢ r ∈ {r | IsUnit r} ∩ σ (a * b) ↔ r ∈ {r | IsUnit r} ∩ σ (b * a)

Tactic:
simpa using fun hr : IsUnit r ↦ unit_mem_mul_comm (r := hr.unit)

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

Goal state before:
pp: R : Type uR
A : Type uA
B : Type uB
inst✝⁴ : CommSemiring R
inst✝³ : CommSemiring A
inst✝² : Semiring B
inst✝¹ : Algebra R A
inst✝ : Algebra R B
s : Set B
hs : adjoin R s = ⊤
⊢ Submodule.span A ↑((TensorProduct.mk R A B) 1).range ≤ Subalgebra.toSubmodule (adjoin A ↑includeRight.range)

Tactic:
exact span_le_adjoin _ _

Goal state after:
Module: Mathlib.Algebra.Algebra.Spectrum.Pi

Goal state before:
pp: A : Type u_2
B : Type u_3
R : Type u_4
inst✝⁴ : CommSemiring R
inst✝³ : NonUnitalRing A
inst✝² : NonUnitalRing B
inst✝¹ : Module R A
inst✝ : Module R B
a : A
b : B
r : R
⊢ r ∈ (quasispectrum R (a, b))ᶜ ↔ r ∈ (quasispectrum R a ∪ quasispectrum R b)ᶜ

Tactic:
simp only [quasispectrum, Set.mem_compl_iff, Set.mem_ofPred_eq, not_forall, not_not,
    Set.mem_union]

Goal state after:
A : Type u_2
B : Type u_3
R : Type u_4
inst✝⁴ : CommSemiring R
inst✝³ : NonUnitalRing A
inst✝² : NonUnitalRing B
inst✝¹ : Module R A
inst✝ : Module R B
a : A
b : B
r : R
⊢ (∃ (h : IsUnit r), IsQuasiregular (-(⋯.unit⁻¹ • (a, b)))) ↔
    ¬((∀ (hr : IsUnit r), ¬IsQuasiregular (-(hr.unit⁻¹ • a))) ∨ ∀ (hr : IsUnit r), ¬IsQuasiregular (-(hr.unit⁻¹ • b)))
Module: Mathlib.LinearAlgebra.Dimension.Constructions

Goal state before:
pp: R : Type u
S : Type u'
M : Type v
M' : Type v'
M₁ : Type v
ι : Type w
ι' : Type w'
η : Type u₁'
φ : η → Type u_1
inst✝¹¹ : Semiring R
inst✝¹⁰ : CommSemiring S
inst✝⁹ : AddCommMonoid M
inst✝⁸ : AddCommMonoid M'
inst✝⁷ : AddCommMonoid M₁
inst✝⁶ : Module R M
inst✝⁵ : StrongRankCondition R
inst✝⁴ : Free R M
inst✝³ : (i : η) → AddCommMonoid (φ i)
inst✝² : (i : η) → Module R (φ i)
inst✝¹ : ∀ (i : η), Free R (φ i)
inst✝ : Fintype η
n : ℕ
hn✝ : Module.rank R M = ↑n
this✝ : Nontrivial R
this : lift.{u, v} ↑n = lift.{v, u} ↑n
hn : lift.{u, v} (Module.rank R M) = lift.{v, u} ↑n
⊢ M ≃ₗ[R] Fin n → R

Tactic:
← @rank_fin_fun R _ _ n

Goal state after:
R : Type u
S : Type u'
M : Type v
M' : Type v'
M₁ : Type v
ι : Type w
ι' : Type w'
η : Type u₁'
φ : η → Type u_1
inst✝¹¹ : Semiring R
inst✝¹⁰ : CommSemiring S
inst✝⁹ : AddCommMonoid M
inst✝⁸ : AddCommMonoid M'
inst✝⁷ : AddCommMonoid M₁
inst✝⁶ : Module R M
inst✝⁵ : StrongRankCondition R
inst✝⁴ : Free R M
inst✝³ : (i : η) → AddCommMonoid (φ i)
inst✝² : (i : η) → Module R (φ i)
inst✝¹ : ∀ (i : η), Free R (φ i)
inst✝ : Fintype η
n : ℕ
hn✝ : Module.rank R M = ↑n
this✝ : Nontrivial R
this : lift.{u, v} ↑n = lift.{v, u} ↑n
hn : lift.{u, v} (Module.rank R M) = lift.{v, u} (Module.rank R (Fin n → R))
⊢ M ≃ₗ[R] Fin n → R
Module: Mathlib.Algebra.Star.NonUnitalSubalgebra

Goal state before:
pp: F : Type v'
R' : Type u'
R : Type u
A : Type v
B : Type w
C : Type w'
inst✝¹² : CommSemiring R
inst✝¹¹ : NonUnitalNonAssocSemiring A
inst✝¹⁰ : Module R A
inst✝⁹ : Star A
inst✝⁸ : NonUnitalNonAssocSemiring B
inst✝⁷ : Module R B
inst✝⁶ : Star B
inst✝⁵ : NonUnitalNonAssocSemiring C
inst✝⁴ : Module R C
inst✝³ : Star C
inst✝² : FunLike F A B
inst✝¹ : NonUnitalAlgHomClass F R A B
inst✝ : StarHomClass F A B
S : NonUnitalStarSubalgebra R A
s : Set A
hs : s = ↑S
x : A
hx : x ∈ s
⊢ star x ∈ s

Tactic:
rw [hs] at hx ⊢

Goal state after:
F : Type v'
R' : Type u'
R : Type u
A : Type v
B : Type w
C : Type w'
inst✝¹² : CommSemiring R
inst✝¹¹ : NonUnitalNonAssocSemiring A
inst✝¹⁰ : Module R A
inst✝⁹ : Star A
inst✝⁸ : NonUnitalNonAssocSemiring B
inst✝⁷ : Module R B
inst✝⁶ : Star B
inst✝⁵ : NonUnitalNonAssocSemiring C
inst✝⁴ : Module R C
inst✝³ : Star C
inst✝² : FunLike F A B
inst✝¹ : NonUnitalAlgHomClass F R A B
inst✝ : StarHomClass F A B
S : NonUnitalStarSubalgebra R A
s : Set A
hs : s = ↑S
x : A
hx : x ∈ ↑S
⊢ star x ∈ ↑S
Module: Mathlib.LinearAlgebra.Dimension.Finite

Goal state before:
pp: R : Type u
M : Type v
inst✝³ : Semiring R
inst✝² : AddCommMonoid M
inst✝¹ : Module R M
inst✝ : Nontrivial R
n : ℕ
hn : finrank R M = n.succ
⊢ 0 < finrank R M

Tactic:
hn

Goal state after:
R : Type u
M : Type v
inst✝³ : Semiring R
inst✝² : AddCommMonoid M
inst✝¹ : Module R M
inst✝ : Nontrivial R
n : ℕ
hn : finrank R M = n.succ
⊢ 0 < n.succ
Module: Mathlib.LinearAlgebra.Dimension.Finite

Goal state before:
pp: case inl
R : Type u
M : Type v
inst✝³ : Semiring R
inst✝² : AddCommMonoid M
inst✝¹ : Module R M
inst✝ : Free R M
h : ∀ (s : Set M) (a : Basis (↑s) R M), ¬s.Finite
h✝ : Subsingleton R
⊢ finrank R M = 0

Tactic:
have := Module.subsingleton R M

Goal state after:
case inl
R : Type u
M : Type v
inst✝³ : Semiring R
inst✝² : AddCommMonoid M
inst✝¹ : Module R M
inst✝ : Free R M
h : ∀ (s : Set M) (a : Basis (↑s) R M), ¬s.Finite
h✝ : Subsingleton R
this : Subsingleton M
⊢ finrank R M = 0
Module: Mathlib.LinearAlgebra.Basis.VectorSpace

Goal state before:
pp: K : Type u_6
V : Type u_7
inst✝² : Field K
inst✝¹ : AddCommGroup V
inst✝ : Module K V
f : V →ₗ[K] K
hf : f ≠ 0
v : ↥f.ker
hv : ↑v ≠ 0
this✝ : LinearIndepOn K _root_.id {v}
b₁ : Basis (↑(this✝.extend ⋯)) K ↥f.ker := Basis.extend this✝
w : V
hw : f w = 1
s : Set V := ⇑f.ker.subtype '' Set.range ⇑b₁
hs : span K s = f.ker
hvs : ↑v ∈ s
n : Set V := insert w s
H₁ : LinearIndepOn K _root_.id n
H₂ : ⊤ ≤ span K n
b : Basis (↑n) K V := Basis.mk H₁ ⋯
x : ↥f.ker
hx : x ∈ Set.range ⇑b₁
this : ↑x ≠ w
⊢ f ((Basis.mk H₁ ⋯) ⟨f.ker.subtype x, ⋯⟩) = (Finsupp.single ⟨f.ker.subtype x, ⋯⟩ 1) ⟨w, ⋯⟩

Tactic:
by simp [this]

Goal state after:
Module: Mathlib.LinearAlgebra.LinearPMap

Goal state before:
pp: R : Type u_1
S : Type u_2
inst✝⁵ : Ring R
inst✝⁴ : Ring S
σ : R →+* S
E : Type u_4
inst✝³ : AddCommGroup E
inst✝² : Module R E
F : Type u_5
inst✝¹ : AddCommGroup F
inst✝ : Module S F
x : E
y : F
H : ∀ (c : R), c • x = 0 → σ c • y = 0
h : x ∈ (mkSpanSingleton' x y H).domain
⊢ ↑(mkSpanSingleton' x y H) ⟨x, h⟩ = y

Tactic:
conv_rhs => rw [← one_smul S y]
  rw [← RingHom.map_one, ← mkSpanSingleton'_apply x y H 1 ?_]
  · congr
    rw [one_smul]
  · rwa [one_smul]

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

Goal state before:
pp: K : Type u
V : Type v
inst✝³ : DivisionRing K
inst✝² : AddCommGroup V
inst✝¹ : Module K V
W W' : Submodule K V
inst✝ : FiniteDimensional K ↥W
f : ↥W ≃ₗ[K] ↥W'
Q : Submodule K V
hQ : IsCompl W Q
eQ : (↥W × ↥Q) ≃ₗ[K] V := W.prodEquivOfIsCompl Q hQ
Q' : Submodule K V
hQ' : IsCompl W' Q'
eQ' : (↥W' × ↥Q') ≃ₗ[K] V := W'.prodEquivOfIsCompl Q' hQ'
⊢ Module.rank K ↥Q = Module.rank K ↥Q'

Tactic:
← Cardinal.add_right_inj_of_lt_aleph0 (γ := Module.rank K W),

Goal state after:
K : Type u
V : Type v
inst✝³ : DivisionRing K
inst✝² : AddCommGroup V
inst✝¹ : Module K V
W W' : Submodule K V
inst✝ : FiniteDimensional K ↥W
f : ↥W ≃ₗ[K] ↥W'
Q : Submodule K V
hQ : IsCompl W Q
eQ : (↥W × ↥Q) ≃ₗ[K] V := W.prodEquivOfIsCompl Q hQ
Q' : Submodule K V
hQ' : IsCompl W' Q'
eQ' : (↥W' × ↥Q') ≃ₗ[K] V := W'.prodEquivOfIsCompl Q' hQ'
⊢ Module.rank K ↥Q + Module.rank K ↥W = Module.rank K ↥Q' + Module.rank K ↥W

K : Type u
V : Type v
inst✝³ : DivisionRing K
inst✝² : AddCommGroup V
inst✝¹ : Module K V
W W' : Submodule K V
inst✝ : FiniteDimensional K ↥W
f : ↥W ≃ₗ[K] ↥W'
Q : Submodule K V
hQ : IsCompl W Q
eQ : (↥W × ↥Q) ≃ₗ[K] V := W.prodEquivOfIsCompl Q hQ
Q' : Submodule K V
hQ' : IsCompl W' Q'
eQ' : (↥W' × ↥Q') ≃ₗ[K] V := W'.prodEquivOfIsCompl Q' hQ'
⊢ Module.rank K ↥W < ℵ₀
Module: Mathlib.LinearAlgebra.FiniteDimensional.Basic

Goal state before:
pp: K : Type u
V : Type v
inst✝³ : DivisionRing K
inst✝² : AddCommGroup V
inst✝¹ : Module K V
ι : Type u_1
inst✝ : Unique ι
h : finrank K V = 1
v : V
hv : v ≠ 0
i : ι
⊢ (basisSingleton ι h v hv) i = v

Tactic:
by
  cases Unique.uniq ‹Unique ι› i
  simp [basisSingleton]

Goal state after:
Module: Mathlib.LinearAlgebra.Dimension.FreeAndStrongRankCondition

Goal state before:
pp: K : Type u
V : Type v
inst✝⁵ : Ring K
inst✝⁴ : StrongRankCondition K
inst✝³ : AddCommGroup V
inst✝² : Module K V
inst✝¹ : Free K V
inst✝ : Module.Finite K V
⊢ finrank K V ≤ 1 ↔ ⊤.IsPrincipal

Tactic:
← Module.rank_le_one_iff_top_isPrincipal,

Goal state after:
K : Type u
V : Type v
inst✝⁵ : Ring K
inst✝⁴ : StrongRankCondition K
inst✝³ : AddCommGroup V
inst✝² : Module K V
inst✝¹ : Free K V
inst✝ : Module.Finite K V
⊢ finrank K V ≤ 1 ↔ Module.rank K V ≤ 1
Module: Mathlib.LinearAlgebra.LinearPMap

Goal state before:
pp: E : Type u_4
inst✝⁵ : AddCommGroup E
F : Type u_5
inst✝⁴ : AddCommGroup F
K : Type u_7
L : Type u_8
inst✝³ : DivisionRing K
inst✝² : DivisionRing L
σ : K →+* L
inst✝¹ : Module K E
inst✝ : Module L F
f : E →ₛₗ.[σ] F
x : E
y : F
hx : x ∉ f.domain
x' : E
hx' : x' ∈ f.domain
c : K
⊢ ↑(f.supSpanSingleton x y hx) ⟨x' + c • x, ⋯⟩ = ↑f ⟨x', hx'⟩ + σ c • y

Tactic:
by
  unfold supSpanSingleton
  rw [sup_apply _ ⟨x', hx'⟩ ⟨c • x, _⟩, mkSpanSingleton'_apply]
  · rfl
  · exact mem_span_singleton.2 ⟨c, rfl⟩

Goal state after:
Module: Mathlib.Algebra.FreeAlgebra

Goal state before:
pp: R : Type u_1
X : Type u_2
inst✝² : CommSemiring R
A : Type u_3
inst✝¹ : Semiring A
inst✝ : Algebra R A
f g : FreeAlgebra R X →ₐ[R] A
w : (lift R).symm f = (lift R).symm g
⊢ f = g

Tactic:
exact (lift R).symm.injective w

Goal state after:
Module: Mathlib.Algebra.CharP.Defs

Goal state before:
pp: R : Type u_1
inst✝¹ : AddMonoidWithOne R
p : ℕ
inst✝ : CharP R p
k : ℕ
this : ∀ (a : ℕ), ↑(p * a) = 0
⊢ ↑(k % p + p * (k / p)) = ↑(k % p)

Tactic:
by simp [this]

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

Goal state before:
pp: R : Type u
inst✝ : Semiring R
ι : Type u_1
l : List ι
f : ι → R[X]
n : ℕ
⊢ (List.map f l).sum.coeff n = (List.map (fun a ↦ (f a).coeff n) l).sum

Tactic:
by
  simp_rw [coeff_list_sum, List.map_map, Function.comp_def, lcoeff_apply]

Goal state after:
Module: Mathlib.Algebra.Polynomial.Degree.Defs

Goal state before:
pp: R : Type u
inst✝ : Semiring R
p : R[X]
hp : p ≠ 0
n : ℕ
hn✝ : ¬n ∉ p.degree
hn : p.degree = some n
⊢ p.degree = ↑(WithBot.unbotD 0 p.degree)

Tactic:
hn

Goal state after:
R : Type u
inst✝ : Semiring R
p : R[X]
hp : p ≠ 0
n : ℕ
hn✝ : ¬n ∉ p.degree
hn : p.degree = some n
⊢ some n = ↑(WithBot.unbotD 0 (some n))
Module: Mathlib.Algebra.Polynomial.Degree.Defs

Goal state before:
pp: R : Type u
inst✝ : Semiring R
a : R
⊢ (C a * X).degree ≤ 1

Tactic:
simpa only [pow_one] using! degree_C_mul_X_pow_le 1 a

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

Goal state before:
pp: case mpr
R : Type u
inst✝ : Semiring R
r : R
φ : R[X]
c : ℕ → R
hc : ∀ (i : ℕ), φ.coeff i = r * c i
c' : ℕ → R := fun i ↦ if i ∈ φ.support then c i else 0
ψ : R[X] := ∑ i ∈ φ.support, (monomial i) (c' i)
⊢ C r ∣ φ

Tactic:
use ψ

Goal state after:
case h
R : Type u
inst✝ : Semiring R
r : R
φ : R[X]
c : ℕ → R
hc : ∀ (i : ℕ), φ.coeff i = r * c i
c' : ℕ → R := ⋯
ψ : R[X] := ⋯
⊢ φ = C r * ψ
Module: Mathlib.Algebra.Polynomial.Degree.Operations

Goal state before:
pp: case inl
R : Type u
inst✝ : Semiring R
p q : R[X]
H : (p + q).natDegree < p.natDegree
h✝ : ¬p.natDegree = q.natDegree
h : p.natDegree < q.natDegree
⊢ False

Tactic:
exact lt_asymm h (by rwa [natDegree_add_eq_right_of_natDegree_lt h] at H)

Goal state after:
Module: Mathlib.Algebra.Polynomial.Degree.Operations

Goal state before:
pp: R : Type u
inst✝ : Semiring R
p q : R[X]
h : p.degree < q.degree
⊢ (p + q).leadingCoeff = q.leadingCoeff

Tactic:
have : coeff p (natDegree q) = 0 := coeff_natDegree_eq_zero_of_degree_lt h
  simp only [leadingCoeff, natDegree_eq_of_degree_eq (degree_add_eq_right_of_degree_lt h), this,
    coeff_add, zero_add]

Goal state after:
Module: Mathlib.Algebra.Polynomial.Degree.Operations

Goal state before:
pp: R : Type u
inst✝ : Semiring R
p q : R[X]
h : p.leadingCoeff * q.leadingCoeff ≠ 0
hp : p ≠ 0
hq : q ≠ 0
⊢ ↑p.natDegree + ↑q.natDegree ≤ (p * q).degree

Tactic:
refine le_degree_of_ne_zero (n := natDegree p + natDegree q) ?_

Goal state after:
R : Type u
inst✝ : Semiring R
p q : R[X]
h : p.leadingCoeff * q.leadingCoeff ≠ 0
hp : p ≠ 0
hq : q ≠ 0
⊢ (p * q).coeff (p.natDegree + q.natDegree) ≠ 0
Module: Mathlib.Algebra.Polynomial.Degree.Defs

Goal state before:
pp: R : Type u
inst✝ : Ring R
p q : R[X]
hd : p.degree = q.degree
hp0 : p ≠ 0
hlc : p.leadingCoeff = q.leadingCoeff
hp : (monomial p.natDegree) p.leadingCoeff + erase p.natDegree p = p
hq : (monomial q.natDegree) q.leadingCoeff + erase q.natDegree q = q
hd' : p.natDegree = q.natDegree
hq0 : q ≠ 0
⊢ (p - q).degree = (erase q.natDegree p + -erase q.natDegree q).degree

Tactic:
by
      conv =>
        lhs
        rw [← hp, ← hq, hlc, hd', add_sub_add_left_eq_sub, sub_eq_add_neg]

Goal state after:
Module: Mathlib.Algebra.Polynomial.Degree.Operations

Goal state before:
pp: case h₀
R : Type u
inst✝ : Semiring R
df dg : ℕ
f g : R[X]
hdf : f.natDegree ≤ df
hdg : g.natDegree ≤ dg
⊢ ∀ b ∈ antidiagonal (df + dg), b ≠ (df, dg) → f.coeff b.1 * g.coeff b.2 = 0

Tactic:
rintro ⟨df', dg'⟩ hmem hne

Goal state after:
case h₀
R : Type u
inst✝ : Semiring R
df dg : ℕ
f g : R[X]
hdf : f.natDegree ≤ df
hdg : g.natDegree ≤ dg
df' dg' : ℕ
hmem : (df', dg') ∈ antidiagonal (df + dg)
hne : (df', dg') ≠ (df, dg)
⊢ f.coeff (df', dg').1 * g.coeff (df', dg').2 = 0
Module: Mathlib.Algebra.Polynomial.Degree.Operations

Goal state before:
pp: R : Type u
inst✝ : Ring R
p q : R[X]
h : p.degree < q.degree
⊢ (p - q).leadingCoeff = -q.leadingCoeff

Tactic:
rw [← q.degree_neg] at h
  rw [sub_eq_add_neg, leadingCoeff_add_of_degree_lt h, leadingCoeff_neg]

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

Goal state before:
pp: R : Type u
inst✝ : Semiring R
f : R[X]
n : ℕ
hn : f.support ⊆ {n}
i : ℕ
hi : ¬i = n
⊢ f.coeff i = 0

Tactic:
← notMem_support_iff

Goal state after:
R : Type u
inst✝ : Semiring R
f : R[X]
n : ℕ
hn : f.support ⊆ {n}
i : ℕ
hi : ¬i = n
⊢ i ∉ f.support
Module: Mathlib.Algebra.Polynomial.Monomial

Goal state before:
pp: case mpr
R : Type u
inst✝ : Semiring R
n : ℕ
a : R
⊢ ((monomial n) a).support ⊆ {n}

Tactic:
exact support_monomial_subset _ _

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

Goal state before:
pp: R : Type u
A : Type z
inst✝² : CommSemiring R
inst✝¹ : Semiring A
inst✝ : Algebra R A
φ : R[X] →ₐ[R] A
p : R[X]
⊢ φ p = eval₂ (algebraMap R A) (φ X) p

Tactic:
← aeval_def,

Goal state after:
R : Type u
A : Type z
inst✝² : CommSemiring R
inst✝¹ : Semiring A
inst✝ : Algebra R A
φ : R[X] →ₐ[R] A
p : R[X]
⊢ φ p = (aeval (φ X)) p
Module: Mathlib.Algebra.Polynomial.AlgebraMap

Goal state before:
pp: case step
R : Type u
inst✝ : CommSemiring R
P : R[X]
h : ∀ (r : R), r • P = 0 → r = 0
Q : R[X]
hQ : P * Q = 0
l : ℕ
IH : ∀ m > l, P.coeff m • Q = 0
⊢ P.coeff l • Q = 0

Tactic:
obtain _ | hl := (natDegree_smul_le (P.coeff l) Q).lt_or_eq

Goal state after:
case step.inl
R : Type u
inst✝ : CommSemiring R
P : R[X]
h : ∀ (r : R), r • P = 0 → r = 0
Q : R[X]
hQ : P * Q = 0
l : ℕ
IH : ∀ m > l, P.coeff m • Q = 0
h✝ : (P.coeff l • Q).natDegree < Q.natDegree
⊢ P.coeff l • Q = 0

case step.inr
R : Type u
inst✝ : CommSemiring R
P : R[X]
h : ∀ (r : R), r • P = 0 → r = 0
Q : R[X]
hQ : P * Q = 0
l : ℕ
IH : ∀ m > l, P.coeff m • Q = 0
hl : (P.coeff l • Q).natDegree = Q.natDegree
⊢ P.coeff l • Q = 0
Module: Mathlib.Algebra.MvPolynomial.Eval

Goal state before:
pp: R : Type u
S₁ : Type v
σ : Type u_1
inst✝¹ : CommSemiring R
inst✝ : CommSemiring S₁
p✝ : MvPolynomial σ R
f : R →+* S₁
g : σ → S₁
p : MvPolynomial σ R
n : σ
ih : ∀ {s : σ →₀ ℕ} {a : R}, eval₂ f g (p * (monomial s) a) = eval₂ f g p * f a * s.prod fun n e ↦ g n ^ e
s : σ →₀ ℕ
a : R
⊢ eval₂ f g (p * (monomial (Finsupp.single n 1 + s)) a) =
    eval₂ f g (p * (monomial (Finsupp.single n 1)) 1) * f a * s.prod fun n e ↦ g n ^ e

Tactic:
simp [ih, prod_single_index, prod_add_index, pow_one, pow_add, mul_assoc, mul_left_comm,
            f.map_one]

Goal state after: