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

Goal state before:
pp: R : Type u_1
inst✝¹¹ : CommSemiring R
M : Submonoid R
S : Type u_2
inst✝¹⁰ : CommSemiring S
inst✝⁹ : Algebra R S
Rₘ : Type u_4
Sₘ : Type u_5
inst✝⁸ : CommSemiring Rₘ
inst✝⁷ : CommSemiring Sₘ
inst✝⁶ : Algebra R Rₘ
inst✝⁵ : IsLocalization M Rₘ
inst✝⁴ : Algebra S Sₘ
i : IsLocalization (Algebra.algebraMapSubmonoid S M) Sₘ
inst✝³ : Algebra Rₘ Sₘ
inst✝² : Algebra R Sₘ
inst✝¹ : IsScalarTower R Rₘ Sₘ
inst✝ : IsScalarTower R S Sₘ
x : R
y : ↥M
⊢ (algebraMap Rₘ Sₘ) (mk' Rₘ x y) = mk' Sₘ ((algebraMap R S) x) ⟨(algebraMap R S) ↑y, ⋯⟩

Tactic:
IsLocalization.eq_mk'_iff_mul_eq,

Goal state after:
R : Type u_1
inst✝¹¹ : CommSemiring R
M : Submonoid R
S : Type u_2
inst✝¹⁰ : CommSemiring S
inst✝⁹ : Algebra R S
Rₘ : Type u_4
Sₘ : Type u_5
inst✝⁸ : CommSemiring Rₘ
inst✝⁷ : CommSemiring Sₘ
inst✝⁶ : Algebra R Rₘ
inst✝⁵ : IsLocalization M Rₘ
inst✝⁴ : Algebra S Sₘ
i : IsLocalization (Algebra.algebraMapSubmonoid S M) Sₘ
inst✝³ : Algebra Rₘ Sₘ
inst✝² : Algebra R Sₘ
inst✝¹ : IsScalarTower R Rₘ Sₘ
inst✝ : IsScalarTower R S Sₘ
x : R
y : ↥M
⊢ (algebraMap Rₘ Sₘ) (mk' Rₘ x y) * (algebraMap S Sₘ) ↑⟨(algebraMap R S) ↑y, ⋯⟩ = (algebraMap S Sₘ) ((algebraMap R S) x)
Module: Mathlib.RingTheory.TensorProduct.Finite

Goal state before:
pp: case add
R : Type u_1
A : Type u_2
B : Type u_3
M : Type u_4
N : Type u_5
inst✝⁴ : CommSemiring R
inst✝³ : Semiring A
inst✝² : Algebra R A
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
h : Module.Finite R M
s : Finset M
hs : Submodule.span R ↑s = ⊤
x y : TensorProduct R A M
hx : x ∈ Submodule.span A ↑(Finset.image (⇑((TensorProduct.mk R A M) 1)) s)
hy : y ∈ Submodule.span A ↑(Finset.image (⇑((TensorProduct.mk R A M) 1)) s)
⊢ x + y ∈ Submodule.span A ↑(Finset.image (⇑((TensorProduct.mk R A M) 1)) s)

Tactic:
exact Submodule.add_mem _ hx hy

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

Goal state before:
pp: R : Type u_1
M : Type u_2
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup M
inst✝² : Module R M
inst✝¹ : Module.Finite R M
inst✝ : Nontrivial M
n : ℕ
f : Fin n → M
hf : Submodule.span R (Set.range f) = ⊤
s : Set ℕ := {m | Submodule.span R (f '' Fin.val ⁻¹' Set.Iio m) ≠ ⊤}
hns : ∀ x ∈ s, x < n
hs₁ : s.Nonempty
hs₂ : BddAbove s
hs : sSup s ∈ s
this : Submodule.span R (f '' Fin.val ⁻¹' Set.Iio (Order.succ (sSup s))) = ⊤
⊢ Submodule.span R (f '' Fin.val ⁻¹' (Set.Iio (sSup s) ∪ {sSup s})) =
    Submodule.span R ({f ⟨sSup s, ⋯⟩} ∪ f '' Fin.val ⁻¹' Set.Iio (sSup s))

Tactic:
Set.preimage_union,

Goal state after:
R : Type u_1
M : Type u_2
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup M
inst✝² : Module R M
inst✝¹ : Module.Finite R M
inst✝ : Nontrivial M
n : ℕ
f : Fin n → M
hf : Submodule.span R (Set.range f) = ⊤
s : Set ℕ := {m | Submodule.span R (f '' Fin.val ⁻¹' Set.Iio m) ≠ ⊤}
hns : ∀ x ∈ s, x < n
hs₁ : s.Nonempty
hs₂ : BddAbove s
hs : sSup s ∈ s
this : Submodule.span R (f '' Fin.val ⁻¹' Set.Iio (Order.succ (sSup s))) = ⊤
⊢ Submodule.span R (f '' (Fin.val ⁻¹' Set.Iio (sSup s) ∪ Fin.val ⁻¹' {sSup s})) =
    Submodule.span R ({f ⟨sSup s, ⋯⟩} ∪ f '' Fin.val ⁻¹' Set.Iio (sSup s))
Module: Mathlib.Algebra.Algebra.Spectrum.Basic

Goal state before:
pp: case neg
R : Type u
A : Type v
inst✝² : CommSemiring R
inst✝¹ : Ring A
inst✝ : Algebra R A
r : Rˣ
s : R
a : A
h : s ∉ σ a
⊢ r • resolvent a s = resolvent (r⁻¹ • a) (r⁻¹ • s)

Tactic:
simp only [resolvent]

Goal state after:
case neg
R : Type u
A : Type v
inst✝² : CommSemiring R
inst✝¹ : Ring A
inst✝ : Algebra R A
r : Rˣ
s : R
a : A
h : s ∉ σ a
⊢ r • (↑ₐ s - a)⁻¹ʳ = (↑ₐ (r⁻¹ • s) - r⁻¹ • a)⁻¹ʳ
Module: Mathlib.Algebra.Algebra.Spectrum.Pi

Goal state before:
pp: ι : Type u_1
R : Type u_4
κ : ι → Type u_5
inst✝² : CommSemiring R
inst✝¹ : (i : ι) → Ring (κ i)
inst✝ : (i : ι) → Algebra R (κ i)
a : (i : ι) → κ i
⊢ {r | IsUnit ((algebraMap R ((i : ι) → κ i)) r - a)} = {x | ∀ (i : ι), IsUnit ((algebraMap R (κ i)) x - a i)}

Tactic:
Pi.isUnit_iff,

Goal state after:
ι : Type u_1
R : Type u_4
κ : ι → Type u_5
inst✝² : CommSemiring R
inst✝¹ : (i : ι) → Ring (κ i)
inst✝ : (i : ι) → Algebra R (κ i)
a : (i : ι) → κ i
⊢ {r | ∀ (i : ι), IsUnit (((algebraMap R ((i : ι) → κ i)) r - a) i)} =
    {x | ∀ (i : ι), IsUnit ((algebraMap R (κ i)) x - a i)}
Module: Mathlib.Algebra.Order.Star.Basic

Goal state before:
pp: case refine_2.refine_2
R : Type u_1
inst✝² : NonUnitalSemiring R
inst✝¹ : PartialOrder R
inst✝ : StarRing R
h_le_iff : ∀ (x y : R), x ≤ y ↔ ∃ s, y = x + star s * s
p : R
hp : p ∈ AddSubmonoid.closure (range fun s ↦ star s * s)
⊢ ∀ (x y : R),
    x ∈ AddSubmonoid.closure (range fun s ↦ star s * s) →
      y ∈ AddSubmonoid.closure (range fun s ↦ star s * s) →
        (∀ (x_1 y : R), y = x_1 + x → x_1 ≤ y) →
          (∀ (x y_1 : R), y_1 = x + y → x ≤ y_1) → ∀ (x_1 y_1 : R), y_1 = x_1 + (x + y) → x_1 ≤ y_1

Tactic:
rintro _ _ _ _ ha hb x y rfl

Goal state after:
case refine_2.refine_2
R : Type u_1
inst✝² : NonUnitalSemiring R
inst✝¹ : PartialOrder R
inst✝ : StarRing R
h_le_iff : ∀ (x y : R), x ≤ y ↔ ∃ s, y = x + star s * s
p : R
hp : p ∈ AddSubmonoid.closure (range fun s ↦ star s * s)
x✝ y✝ : R
hx✝ : x✝ ∈ AddSubmonoid.closure (range fun s ↦ star s * s)
hy✝ : y✝ ∈ AddSubmonoid.closure (range fun s ↦ star s * s)
ha : ∀ (x y : R), y = x + x✝ → x ≤ y
hb : ∀ (x y : R), y = x + y✝ → x ≤ y
x : R
⊢ x ≤ x + (x✝ + y✝)
Module: Mathlib.LinearAlgebra.Dimension.Constructions

Goal state before:
pp: R : Type u
M : Type v
inst✝³ : Ring R
inst✝² : AddCommGroup M
inst✝¹ : Module R M
inst✝ : Nontrivial R
M' : Submodule R M
x✝¹ : { s // LinearIndepOn R id s }
s : Set (M ⧸ M')
hs : LinearIndepOn R id s
x✝ : { s // LinearIndepOn R id s }
t : Set ↥M'
ht : LinearIndepOn R id t
⊢ #↑↑⟨s, hs⟩ + #↑↑⟨t, ht⟩ ≤ Module.rank R M

Tactic:
choose f hf using Submodule.Quotient.mk_surjective M'

Goal state after:
R : Type u
M : Type v
inst✝³ : Ring R
inst✝² : AddCommGroup M
inst✝¹ : Module R M
inst✝ : Nontrivial R
M' : Submodule R M
x✝¹ : { s // LinearIndepOn R id s }
s : Set (M ⧸ M')
hs : LinearIndepOn R id s
x✝ : { s // LinearIndepOn R id s }
t : Set ↥M'
ht : LinearIndepOn R id t
f : M ⧸ M' → M
hf : ∀ (b : M ⧸ M'), Submodule.Quotient.mk (f b) = b
⊢ #↑↑⟨s, hs⟩ + #↑↑⟨t, ht⟩ ≤ Module.rank R M
Module: Mathlib.LinearAlgebra.Dimension.Finite

Goal state before:
pp: R : Type u
M : Type v
inst✝² : Semiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
n : ℕ
H : ∀ (s : Finset M), (LinearIndependent R fun i ↦ ↑i) → s.card ≤ n
s : Set M
li : LinearIndependent R Subtype.val
t : Finset ↑s
⊢ LinearIndependent R fun i ↦ ↑i

Tactic:
apply linearIndependent_finset_map_embedding_subtype _ li

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

Goal state before:
pp: R : Type u_1
M : Type u_2
inst✝⁴ : Ring R
inst✝³ : AddCommGroup M
inst✝² : Module R M
inst✝¹ : IsDomain R
inst✝ : IsTorsionFree R M
⊢ (∀ (x : M), ∃ a, a ≠ 0 ∧ a • x = 0) ↔ ∀ (x : M), x = 0

Tactic:
smul_eq_zero,

Goal state after:
R : Type u_1
M : Type u_2
inst✝⁴ : Ring R
inst✝³ : AddCommGroup M
inst✝² : Module R M
inst✝¹ : IsDomain R
inst✝ : IsTorsionFree R M
⊢ (∀ (x : M), ∃ a, a ≠ 0 ∧ (a = 0 ∨ x = 0)) ↔ ∀ (x : M), x = 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
⊢ ∃ n b i j, i ≠ j ∧ ↑v = b i ∧ f = b.coord j

Tactic:
have hvs : ↑v ∈ s := by
    refine ⟨v, ?_, by simp⟩
    simp [b₁, this.subset_extend _ _]

Goal state after:
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 b i j, i ≠ j ∧ ↑v = b i ∧ f = b.coord j
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✝ : Free R M
h : ∀ (s : Set M) (a : Basis (↑s) R M), ¬s.Finite
⊢ finrank R M = 0

Tactic:
cases subsingleton_or_nontrivial R
  · have := Module.subsingleton R M
    exact (h ∅ ⟨LinearEquiv.ofSubsingleton _ _⟩ Set.finite_empty).elim
  obtain ⟨_, ⟨b⟩⟩ := (Module.free_iff_set R M).mp ‹_›
  have := Set.Infinite.to_subtype (h _ b)
  exact b.linearIndependent.finrank_eq_zero_of_infinite

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

Goal state before:
pp: R : Type u
M : Type v
inst✝⁵ : Ring R
inst✝⁴ : AddCommGroup M
inst✝³ : Module R M
inst✝² : IsDomain R
inst✝¹ : IsTorsionFree R M
inst✝ : StrongRankCondition R
v : M
n : v ≠ 0
h : ∀ (w : M), ∃ c, c • v = w
⊢ Module.rank R M = 1

Tactic:
have := nontrivial_of_invariantBasisNumber R
  obtain ⟨b⟩ := (Basis.basis_singleton_iff.{_, _, u} PUnit).mpr ⟨v, n, h⟩
  rw [rank_eq_card_basis b, Fintype.card_punit, Nat.cast_one]

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

Goal state before:
pp: case pos
R : Type u
S : Type v
a : R
inst✝¹ : Semiring R
p : R[X]
inst✝ : Semiring S
f : R →+* S
x : S
h : Commute (f a) x
k : ℕ
hk : k = 0
⊢ Commute (f ((C a).coeff k)) x

pp: case neg
R : Type u
S : Type v
a : R
inst✝¹ : Semiring R
p : R[X]
inst✝ : Semiring S
f : R →+* S
x : S
h : Commute (f a) x
k : ℕ
hk : ¬k = 0
⊢ Commute (f ((C a).coeff k)) x

Tactic:
· simp only [hk, h, coeff_C_zero]

Goal state after:
case neg
R : Type u
S : Type v
a : R
inst✝¹ : Semiring R
p : R[X]
inst✝ : Semiring S
f : R →+* S
x : S
h : Commute (f a) x
k : ℕ
hk : ¬k = 0
⊢ Commute (f ((C a).coeff k)) x
Module: Mathlib.Algebra.Polynomial.Eval.Defs

Goal state before:
pp: R : Type u_1
inst✝ : CommSemiring R
n : ℕ
x : R
⊢ eval x (∑ i ∈ range n, X ^ i) = ∑ i ∈ range n, x ^ i

Tactic:
simp [eval_finsetSum]

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

Goal state before:
pp: R : Type u_1
A : Type u_4
M : Type u_7
inst✝³ : CommSemiring R
inst✝² : Semiring A
inst✝¹ : Algebra R A
inst✝ : Monoid M
F : R[M] →ₐ[R] A
f : R[M]
| F f

Tactic:
rw [lift_unique' F]

Goal state after:
R : Type u_1
A : Type u_4
M : Type u_7
inst✝³ : CommSemiring R
inst✝² : Semiring A
inst✝¹ : Algebra R A
inst✝ : Monoid M
F : R[M] →ₐ[R] A
f : R[M]
| ((lift R A M) ((↑F).comp (of R M))) f
Module: Mathlib.Algebra.Polynomial.Coeff

Goal state before:
pp: R : Type u
a : R
n : ℕ
inst✝ : Semiring R
p : R[ℕ]
⊢ (C a * { toFinsupp := p }).coeff n = a * { toFinsupp := p }.coeff n

Tactic:
← monomial_zero_left,

Goal state after:
R : Type u
a : R
n : ℕ
inst✝ : Semiring R
p : R[ℕ]
⊢ ((monomial 0) a * { toFinsupp := p }).coeff n = a * { toFinsupp := p }.coeff n
Module: Mathlib.Algebra.Polynomial.Coeff

Goal state before:
pp: R : Type u
inst✝ : Semiring R
n : ℕ
a : R
p : R[ℕ]
⊢ ({ toFinsupp := p } * C a).coeff n = { toFinsupp := p }.coeff n * a

Tactic:
← monomial_zero_left,

Goal state after:
R : Type u
inst✝ : Semiring R
n : ℕ
a : R
p : R[ℕ]
⊢ ({ toFinsupp := p } * (monomial 0) a).coeff n = { toFinsupp := p }.coeff n * a
Module: Mathlib.Algebra.MonoidAlgebra.Basic

Goal state before:
pp: R : Type u_1
A : Type u_4
M : Type u_7
inst✝³ : CommSemiring R
inst✝² : AddMonoid M
inst✝¹ : Semiring A
inst✝ : Algebra R A
F : R[M] →ₐ[R] A
f : R[M]
| F f

Tactic:
rw [lift_unique' F]

Goal state after:
R : Type u_1
A : Type u_4
M : Type u_7
inst✝³ : CommSemiring R
inst✝² : AddMonoid M
inst✝¹ : Semiring A
inst✝ : Algebra R A
F : R[M] →ₐ[R] A
f : R[M]
| ((lift R A M) ((↑F).comp (of R M))) f
Module: Mathlib.Algebra.Polynomial.Coeff

Goal state before:
pp: R : Type u
inst✝ : Semiring R
n : ℕ
P Q : R[X]
hPQ : X ^ n * P = X ^ n * Q
i : ℕ
⊢ (X ^ n * P).coeff (i + n) = Q.coeff i

Tactic:
hPQ,

Goal state after:
R : Type u
inst✝ : Semiring R
n : ℕ
P Q : R[X]
hPQ : X ^ n * P = X ^ n * Q
i : ℕ
⊢ (X ^ n * Q).coeff (i + n) = Q.coeff i
Module: Mathlib.Algebra.Polynomial.Degree.Defs

Goal state before:
pp: R : Type u
a : R
inst✝ : Semiring R
ha : a ≠ 0
⊢ (C a).support.max = 0

Tactic:
← monomial_zero_left,

Goal state after:
R : Type u
a : R
inst✝ : Semiring R
ha : a ≠ 0
⊢ ((monomial 0) a).support.max = 0
Module: Mathlib.Algebra.Polynomial.Degree.Defs

Goal state before:
pp: R : Type u
inst✝ : Semiring R
p : R[X]
h : p ≠ 0
⊢ p.degree.succ = p.natDegree + 1

Tactic:
by
  rw [degree_eq_natDegree h]
  exact WithBot.succ_coe p.natDegree

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

Goal state before:
pp: case pos
R : Type u
inst✝ : Semiring R
p q : R[X]
i j : ℕ
h₁ : (i, j).1 + (i, j).2 = p.natDegree + q.natDegree
h₂ : (i, j) ≠ (p.natDegree, q.natDegree)
H : p.natDegree < i
⊢ p.coeff (i, j).1 * q.coeff (i, j).2 = 0

pp: case neg
R : Type u
inst✝ : Semiring R
p q : R[X]
i j : ℕ
h₁ : (i, j).1 + (i, j).2 = p.natDegree + q.natDegree
h₂ : (i, j) ≠ (p.natDegree, q.natDegree)
H : ¬p.natDegree < i
⊢ p.coeff (i, j).1 * q.coeff (i, j).2 = 0

Tactic:
· rw [coeff_eq_zero_of_degree_lt
              (lt_of_le_of_lt degree_le_natDegree (WithBot.coe_lt_coe.2 H)),
            zero_mul]

Goal state after:
case neg
R : Type u
inst✝ : Semiring R
p q : R[X]
i j : ℕ
h₁ : (i, j).1 + (i, j).2 = p.natDegree + q.natDegree
h₂ : (i, j) ≠ (p.natDegree, q.natDegree)
H : ¬p.natDegree < i
⊢ p.coeff (i, j).1 * q.coeff (i, j).2 = 0
Module: Mathlib.Data.Nat.WithBot

Goal state before:
pp: case coe.coe
a✝¹ a✝ : ℕ
⊢ ↑a✝¹ + ↑a✝ = 3 ↔ ↑a✝¹ = 0 ∧ ↑a✝ = 3 ∨ ↑a✝¹ = 1 ∧ ↑a✝ = 2 ∨ ↑a✝¹ = 2 ∧ ↑a✝ = 1 ∨ ↑a✝¹ = 3 ∧ ↑a✝ = 0

Tactic:
simp [← WithBot.coe_add, Nat.add_eq_three_iff]

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

Goal state before:
pp: R : Type u
a b c d : R
inst✝ : Semiring R
ha : a ≠ 0
⊢ (C a * X ^ 3 + C b * X ^ 2 + C c * X + C d).degree = 3

Tactic:
rw [add_assoc, add_assoc, ← add_assoc (C b * X ^ 2),
    degree_add_eq_left_of_degree_lt <| degree_quadratic_lt_degree_C_mul_X_cb ha,
    degree_C_mul_X_pow 3 ha]
  rfl

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

Goal state before:
pp: case h₀.inl
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)
h : df < df'
⊢ f.coeff (df', dg').1 * g.coeff (df', dg').2 = 0

Tactic:
rw [coeff_eq_zero_of_natDegree_lt (hdf.trans_lt h), zero_mul]

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

Goal state before:
pp: R : Type u
inst✝¹ : Semiring R
inst✝ : Nontrivial R
p : R[X]
n : ℕ
hp : p ≠ 0
⊢ (X ^ n * p).natDegree = p.natDegree + n

Tactic:
rw [commute_X_pow, natDegree_mul_X_pow n hp]

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

Goal state before:
pp: R : Type u
inst✝ : Semiring R
p : R[X]
⊢ map (RingHom.id R) p = p

Tactic:
simp [Polynomial.ext_iff, coeff_map]

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

Goal state before:
pp: case inr
R : Type u
inst✝¹ : Semiring R
inst✝ : NoZeroDivisors R
q p : R[X]
hq : q ≠ 0
hp : p ≠ 0
⊢ ↑p.natDegree ≤ ↑p.natDegree + ↑q.natDegree

Tactic:
exact WithBot.coe_le_coe.2 (Nat.le_add_right _ _)

Goal state after:
Module: Mathlib.Data.Finsupp.Antidiagonal

Goal state before:
pp: case refine_1
α : Type u
inst✝¹ : DecidableEq α
β : Type u_1
inst✝ : DecidableEq β
f : α ↪ β
y : α →₀ ℕ
u v : β →₀ ℕ
x✝ : ∃ a b, a + b = y ∧ embDomain f a = u ∧ embDomain f b = v
w z : α →₀ ℕ
h : w + z = y
hw : embDomain f w = u
hz : embDomain f z = v
⊢ u + v = embDomain f y

Tactic:
rw [← hw, ← hz, ← embDomain_add, h]

Goal state after:
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 q : MvPolynomial σ R
f : R →+* S₁
g : σ → S₁
hq : eval₂ f g q = 0
⊢ eval₂ f g (p * q) = 0

Tactic:
by
  simp [eval₂_mul f g, hq]

Goal state after:
Module: Mathlib.Algebra.MvPolynomial.Eval

Goal state before:
pp: R : Type u
σ : Type u_1
inst✝ : CommSemiring R
τ : Type u_2
f : σ → MvPolynomial τ R
g : τ → R
p : MvPolynomial σ R
⊢ (eval (⇑(eval g) ∘ f)) p = (eval g) (eval₂ C f p)

Tactic:
by
  rw [eval₂_comp_left (eval g)]
  unfold eval; simp only [coe_eval₂Hom]
  congr with a; simp

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

Goal state before:
pp: case mpr
R : Type u
σ : Type u_1
inst✝ : CommSemiring R
r : R
φ : MvPolynomial σ R
h : ∀ (i : σ →₀ ℕ), r ∣ coeff i φ
⊢ C r ∣ φ

Tactic:
choose C hc using h

Goal state after:
case mpr
R : Type u
σ : Type u_1
inst✝ : CommSemiring R
r : R
φ : MvPolynomial σ R
C : (σ →₀ ℕ) → R
hc : ∀ (i : σ →₀ ℕ), coeff i φ = r * C i
⊢ MvPolynomial.C r ∣ φ
Module: Mathlib.Algebra.MvPolynomial.Basic

Goal state before:
pp: case mpr
R : Type u
σ : Type u_1
inst✝ : CommSemiring R
r : R
φ : MvPolynomial σ R
C : (σ →₀ ℕ) → R
hc : ∀ (i : σ →₀ ℕ), coeff i φ = r * C i
⊢ MvPolynomial.C r ∣ φ

Tactic:
let c' : (σ →₀ ℕ) → R := fun i => if i ∈ φ.support then C i else 0
      let ψ : MvPolynomial σ R := ∑ i ∈ φ.support, monomial i (c' i)
      use ψ
      apply MvPolynomial.ext
      intro i
      simp only [ψ, c', coeff_C_mul, coeff_sum, coeff_monomial, Finset.sum_ite_eq']
      split_ifs with hi
      · rw [hc]
      · rw [notMem_support_iff] at hi
        rwa [mul_zero]

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

Goal state before:
pp: R : Type u
σ : Type u_1
n : σ
inst✝ : CommSemiring R
P Q : MvPolynomial σ R
hPQ : X n * P = X n * Q
i : σ →₀ ℕ
⊢ coeff (Finsupp.single n 1 + i) (X n * P) = coeff i Q

Tactic:
hPQ,

Goal state after:
R : Type u
σ : Type u_1
n : σ
inst✝ : CommSemiring R
P Q : MvPolynomial σ R
hPQ : X n * P = X n * Q
i : σ →₀ ℕ
⊢ coeff (Finsupp.single n 1 + i) (X n * Q) = coeff i Q
Module: Mathlib.Algebra.MvPolynomial.Rename

Goal state before:
pp: case neg
σ : Type u_1
τ : Type u_2
R : Type u_4
inst✝¹ : CommSemiring R
f : σ → τ
hf : Injective f
s : τ →₀ ℕ
c : R
inst✝ : Decidable (↑s.support ⊆ range f)
h : ¬↑s.support ⊆ range f
⊢ (killCompl hf) ((monomial s) c) = 0

Tactic:
exact killCompl_monomial_eq_zero_of_not_subset hf c h

Goal state after:
Module: Mathlib.Algebra.MvPolynomial.Rename

Goal state before:
pp: case neg
σ : Type u_1
τ : Type u_2
R : Type u_4
inst✝ : CommSemiring R
f : σ → τ
hf : Injective f
p : MvPolynomial τ R
s : σ →₀ ℕ
u : τ →₀ ℕ
r : R
h : ¬↑u.support ⊆ range f
⊢ coeff s 0 = coeff (Finsupp.mapDomain f s) ((monomial u) r)

Tactic:
simp only [coeff_zero, coeff_monomial, right_eq_ite_iff]

Goal state after:
case neg
σ : Type u_1
τ : Type u_2
R : Type u_4
inst✝ : CommSemiring R
f : σ → τ
hf : Injective f
p : MvPolynomial τ R
s : σ →₀ ℕ
u : τ →₀ ℕ
r : R
h : ¬↑u.support ⊆ range f
⊢ u = Finsupp.mapDomain f s → 0 = r
Module: Mathlib.Algebra.MvPolynomial.Degrees

Goal state before:
pp: R : Type u
σ : Type u_1
inst✝ : CommSemiring R
p : MvPolynomial σ R
i : σ
⊢ i ∈ p.degrees ↔ ∃ d, coeff d p ≠ 0 ∧ i ∈ d.support

Tactic:
classical
  simp only [degrees_def, Multiset.mem_sup, ← mem_support_iff, Finsupp.mem_toMultiset]

Goal state after:
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
f : R →+* S₁
g : S₁ → R
hg : g 0 = 0
φ : MvPolynomial σ S₁
⊢ (map f) (ofCoeff (mapRange g hg φ.coeff)) = φ ↔ ∀ (d : σ →₀ ℕ), f (g (coeff d φ)) = coeff d φ

Tactic:
MvPolynomial.ext_iff,

Goal state after:
R : Type u
S₁ : Type v
σ : Type u_1
inst✝¹ : CommSemiring R
inst✝ : CommSemiring S₁
f : R →+* S₁
g : S₁ → R
hg : g 0 = 0
φ : MvPolynomial σ S₁
⊢ (∀ (m : σ →₀ ℕ), coeff m ((map f) (ofCoeff (mapRange g hg φ.coeff))) = coeff m φ) ↔
    ∀ (d : σ →₀ ℕ), f (g (coeff d φ)) = coeff d φ
Module: Mathlib.Data.Finsupp.Fin

Goal state before:
pp: n : ℕ
M : Type u_1
inst✝ : Zero M
y : M
j : Fin (n + 1)
⊢ (cons y 0) j = (single 0 y) j

Tactic:
cases j using Fin.cases

Goal state after:
case zero
n : ℕ
M : Type u_1
inst✝ : Zero M
y : M
⊢ (cons y 0) 0 = (single 0 y) 0

case succ
n : ℕ
M : Type u_1
inst✝ : Zero M
y : M
i✝ : Fin n
⊢ (cons y 0) i✝.succ = (single 0 y) i✝.succ
Module: Mathlib.Data.Finsupp.Fin

Goal state before:
pp: n : ℕ
i : Fin n
M : Type u_1
inst✝ : Zero M
y : M
j : Fin (n + 1)
⊢ (cons 0 (single i y)) j = (single i.succ y) j

Tactic:
cases j using Fin.cases

Goal state after:
case zero
n : ℕ
i : Fin n
M : Type u_1
inst✝ : Zero M
y : M
⊢ (cons 0 (single i y)) 0 = (single i.succ y) 0

case succ
n : ℕ
i : Fin n
M : Type u_1
inst✝ : Zero M
y : M
i✝ : Fin n
⊢ (cons 0 (single i y)) i✝.succ = (single i.succ y) i✝.succ
Module: Mathlib.Algebra.BigOperators.Finsupp.Fin

Goal state before:
pp: M : Type u_1
inst✝ : AddCommMonoid M
n : ℕ
σ : Fin n →₀ M
i : M
⊢ ((cons i σ).sum fun x e ↦ e) = i + σ.sum fun x e ↦ e

Tactic:
rw [sum_fintype _ _ (fun _ => rfl), sum_fintype _ _ (fun _ => rfl)]
  exact Fin.sum_cons i σ

Goal state after:
Module: Mathlib.Algebra.MvPolynomial.Variables

Goal state before:
pp: R : Type u
S : Type v
σ : Type u_1
inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
f₁ : R →+* S
g₁ g₂ : σ → S
p₁ : MvPolynomial σ R
h : ∀ i ∈ p₁.vars, i ∈ p₁.vars → g₁ i = g₂ i
⊢ (eval₂Hom f₁ g₁) p₁ = (eval₂Hom f₁ g₂) p₁

Tactic:
p₁.as_sum

Goal state after:
R : Type u
S : Type v
σ : Type u_1
inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
f₁ : R →+* S
g₁ g₂ : σ → S
p₁ : MvPolynomial σ R
h : ∀ i ∈ p₁.vars, i ∈ p₁.vars → g₁ i = g₂ i
⊢ (eval₂Hom f₁ g₁) (∑ v ∈ p₁.support, (monomial v) (coeff v p₁)) =
    (eval₂Hom f₁ g₂) (∑ v ∈ p₁.support, (monomial v) (coeff v p₁))
Module: Mathlib.Algebra.MvPolynomial.Degrees

Goal state before:
pp: R : Type u
σ : Type u_1
inst✝ : CommSemiring R
s t : Multiset σ
⊢ degreesLE R σ (s + t) = degreesLE R σ s * degreesLE R σ t

Tactic:
classical
  rw [le_antisymm_iff, Submodule.mul_le]
  refine ⟨fun x hx ↦ x.as_sum ▸ sum_mem fun i hi ↦ ?_,
    fun x hx y hy ↦ degrees_mul_le.trans (add_le_add hx hy)⟩
  replace hi : i.toMultiset ≤ s + t := (Finset.le_sup hi).trans hx
  let a := (i.toMultiset - t).toFinsupp
  let b := (i.toMultiset ⊓ t).toFinsupp
  have : a + b = i := Multiset.toFinsupp.symm.injective (by simp [a, b, Multiset.sub_add_inter])
  have ha : a.toMultiset ≤ s := by simpa [a, add_comm (a := t)] using hi
  have hb : b.toMultiset ≤ t := by simp [b, Multiset.inter_le_right]
  rw [show monomial i (x.coeff i) = monomial a (x.coeff i) * monomial b 1 by simp [this]]
  exact Submodule.mul_mem_mul ((degrees_monomial _ _).trans ha) ((degrees_monomial _ _).trans hb)

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

Goal state before:
pp: case a
R : Type u
inst✝ : Semiring R
p : R[X]
hp : p ≠ 0
n : ℕ
⊢ (p * X ^ n).natTrailingDegree ≤ p.natTrailingDegree + n

pp: case a
R : Type u
inst✝ : Semiring R
p : R[X]
hp : p ≠ 0
n : ℕ
⊢ p.natTrailingDegree + n ≤ (p * X ^ n).natTrailingDegree

Tactic:
· refine natTrailingDegree_le_of_ne_zero fun h => mt trailingCoeff_eq_zero.mp hp ?_
    rwa [trailingCoeff, ← coeff_mul_X_pow]

Goal state after:
case a
R : Type u
inst✝ : Semiring R
p : R[X]
hp : p ≠ 0
n : ℕ
⊢ p.natTrailingDegree + n ≤ (p * X ^ n).natTrailingDegree
Module: Mathlib.Algebra.MvPolynomial.Equiv

Goal state before:
pp: R : Type u
S₁ : Type v
σ : Type u_1
inst✝³ : CommSemiring R
inst✝² : IsEmpty σ
inst✝¹ : CommSemiring S₁
inst✝ : Algebra R S₁
f : σ → S₁
this : aeval f = (Algebra.ofId R S₁).comp ↑(isEmptyAlgEquiv R σ)
⊢ Injective ⇑((Algebra.ofId R S₁).comp ↑(isEmptyAlgEquiv R σ)) ↔ Injective ⇑(algebraMap R S₁)

Tactic:
← Injective.of_comp_iff' _ (@isEmptyAlgEquiv R σ _ _).bijective

Goal state after:
R : Type u
S₁ : Type v
σ : Type u_1
inst✝³ : CommSemiring R
inst✝² : IsEmpty σ
inst✝¹ : CommSemiring S₁
inst✝ : Algebra R S₁
f : σ → S₁
this : aeval f = (Algebra.ofId R S₁).comp ↑(isEmptyAlgEquiv R σ)
⊢ Injective ⇑((Algebra.ofId R S₁).comp ↑(isEmptyAlgEquiv R σ)) ↔ Injective (⇑(algebraMap R S₁) ∘ ⇑(isEmptyAlgEquiv R σ))
Module: Mathlib.Algebra.MvPolynomial.Equiv

Goal state before:
pp: R : Type u
S₁ : Type v
inst✝ : CommSemiring R
r : R
⊢ (optionEquivLeft R S₁) (C r) = Polynomial.C (C r)

Tactic:
by
  simp only [optionEquivLeft_apply, aeval_C, Polynomial.algebraMap_apply, algebraMap_eq]

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

Goal state before:
pp: R : Type u_1
inst✝ : Semiring R
f : R[X]
⊢ f.reverse.coeff f.reverse.natDegree = f.trailingCoeff

Tactic:
reverse_natDegree,

Goal state after:
R : Type u_1
inst✝ : Semiring R
f : R[X]
⊢ f.reverse.coeff (f.natDegree - f.natTrailingDegree) = f.trailingCoeff