mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.LinearAlgebra.Dimension.FreeAndStrongRankCondition

Goal state before:
pp: case mpr
K : Type u
V : Type v
inst✝⁴ : Ring K
inst✝³ : StrongRankCondition K
inst✝² : AddCommGroup V
inst✝¹ : Module K V
inst✝ : Free K V
κ : Type v
b : Basis κ K V
v₀ : V
hv₀ : ∀ (v : V), ∃ r, r • v₀ = v
h : K ∙ v₀ = ⊤
⊢ Module.rank K V ≤ 1

Tactic:
rw [← rank_top, ← h]

Goal state after:
case mpr
K : Type u
V : Type v
inst✝⁴ : Ring K
inst✝³ : StrongRankCondition K
inst✝² : AddCommGroup V
inst✝¹ : Module K V
inst✝ : Free K V
κ : Type v
b : Basis κ K V
v₀ : V
hv₀ : ∀ (v : V), ∃ r, r • v₀ = v
h : K ∙ v₀ = ⊤
⊢ Module.rank K ↥(K ∙ v₀) ≤ 1
Module: Mathlib.LinearAlgebra.Dimension.FreeAndStrongRankCondition

Goal state before:
pp: K : Type u
V : Type v
inst✝⁴ : Ring K
inst✝³ : StrongRankCondition K
inst✝² : AddCommGroup V
inst✝¹ : Module K V
s : Submodule K V
inst✝ : Free K ↥s
⊢ Module.rank K ↥s ≤ 1 ↔ ∃ v₀, s ≤ K ∙ v₀

Tactic:
have := nontrivial_of_invariantBasisNumber K
  constructor
  · rw [rank_submodule_le_one_iff]
    rintro ⟨v₀, _, h⟩
    exact ⟨v₀, h⟩
  · rintro ⟨v₀, h⟩
    obtain ⟨κ, b⟩ := Module.Free.exists_basis (R := K) (M := s)
    simpa [b.mk_eq_rank''] using b.linearIndependent.map' _ (ker_inclusion _ _ h)
      |>.cardinal_le_rank.trans (rank_span_le {v₀})

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

Goal state before:
pp: k : Type u₁
G : Type u₂
inst✝² : Semiring k
inst✝¹ : Mul G
inst✝ : DecidableEq G
x : k[G]
r : k
a : G
⊢ (single a r * x).coeff.support ⊆ image (fun x ↦ a * x) x.coeff.support

Tactic:
support_coeff_mul_subset,

Goal state after:
k : Type u₁
G : Type u₂
inst✝² : Semiring k
inst✝¹ : Mul G
inst✝ : DecidableEq G
x : k[G]
r : k
a : G
⊢ (single a r).coeff.support * x.coeff.support ⊆ image (fun x ↦ a * x) x.coeff.support
Module: Mathlib.Algebra.MonoidAlgebra.Support

Goal state before:
pp: k : Type u₁
G : Type u₂
inst✝² : Semiring k
inst✝¹ : Mul G
inst✝ : DecidableEq G
x : k[G]
r : k
a : G
⊢ (x * single a r).coeff.support ⊆ image (fun x ↦ x * a) x.coeff.support

Tactic:
support_coeff_mul_subset,

Goal state after:
k : Type u₁
G : Type u₂
inst✝² : Semiring k
inst✝¹ : Mul G
inst✝ : DecidableEq G
x : k[G]
r : k
a : G
⊢ x.coeff.support * (single a r).coeff.support ⊆ image (fun x ↦ x * a) x.coeff.support
Module: Mathlib.Algebra.CharP.Defs

Goal state before:
pp: R : Type u_1
inst✝² : AddMonoidWithOne R
p : ℕ
inst✝¹ : CharP R p
a : ℕ
inst✝ : a.AtLeastTwo
h : p ∣ a
⊢ OfNat.ofNat a = 0

Tactic:
← CharP.cast_eq_zero_iff R p

Goal state after:
R : Type u_1
inst✝² : AddMonoidWithOne R
p : ℕ
inst✝¹ : CharP R p
a : ℕ
inst✝ : a.AtLeastTwo
h : ↑a = 0
⊢ OfNat.ofNat a = 0
Module: Mathlib.Data.Nat.Prime.Defs

Goal state before:
pp: case neg
n : ℕ
n1 : n ≠ 1
n0 : ¬n = 0
n2 : 2 ≤ n
⊢ n.minFacProp n.minFac

Tactic:
simp only [minFac_eq]

Goal state after:
case neg
n : ℕ
n1 : n ≠ 1
n0 : ¬n = 0
n2 : 2 ≤ n
⊢ n.minFacProp (if 2 ∣ n then 2 else n.minFacAux 3)
Module: Mathlib.LinearAlgebra.LinearPMap

Goal state before:
pp: R : Type u_1
inst✝⁴ : Ring R
E : Type u_4
inst✝³ : AddCommGroup E
inst✝² : Module R E
F : Type u_5
inst✝¹ : AddCommGroup F
inst✝ : Module R F
f : E →ₗ.[R] F
hf : f.toFun.ker = ⊥
x : F
y : E
hv : (x, y) ∈ Submodule.map (↑(LinearEquiv.prodComm R E F)) f.graph
hv' : (x, y).1 = 0
⊢ (x, y).2 = 0

Tactic:
subst hv'

Goal state after:
R : Type u_1
inst✝⁴ : Ring R
E : Type u_4
inst✝³ : AddCommGroup E
inst✝² : Module R E
F : Type u_5
inst✝¹ : AddCommGroup F
inst✝ : Module R F
f : E →ₗ.[R] F
hf : f.toFun.ker = ⊥
y : E
hv : (0, y) ∈ Submodule.map (↑(LinearEquiv.prodComm R E F)) f.graph
⊢ (0, y).2 = 0
Module: Mathlib.Algebra.MonoidAlgebra.Degree

Goal state before:
pp: R : Type u_1
A : Type u_3
B : Type u_5
inst✝⁶ : SemilatticeSup B
inst✝⁵ : OrderBot B
inst✝⁴ : Semiring R
inst✝³ : Add A
inst✝² : Add B
inst✝¹ : AddLeftMono B
inst✝ : AddRightMono B
degb : A → B
degbm : ∀ (a b : A), degb (a + b) ≤ degb a + degb b
f g : R[A]
⊢ (f * g).coeff.support.sup degb ≤ f.coeff.support.sup degb + g.coeff.support.sup degb

Tactic:
support_coeff_mul_subset,

Goal state after:
R : Type u_1
A : Type u_3
B : Type u_5
inst✝⁶ : SemilatticeSup B
inst✝⁵ : OrderBot B
inst✝⁴ : Semiring R
inst✝³ : Add A
inst✝² : Add B
inst✝¹ : AddLeftMono B
inst✝ : AddRightMono B
degb : A → B
degbm : ∀ (a b : A), degb (a + b) ≤ degb a + degb b
f g : R[A]
⊢ (f.coeff.support + g.coeff.support).sup degb ≤ f.coeff.support.sup degb + g.coeff.support.sup degb
Module: Mathlib.Algebra.MonoidAlgebra.Degree

Goal state before:
pp: R : Type u_1
A : Type u_3
B : Type u_5
inst✝² : Semiring R
inst✝¹ : SemilatticeSup B
inst✝ : OrderBot B
D : A → B
s : R[A]
hs : s.coeff.support.Nonempty
⊢ s.coeff.support.sup (WithBot.some ∘ D) = ↑(s.coeff.support.sup D)

Tactic:
← Finset.coe_sup' hs,

Goal state after:
R : Type u_1
A : Type u_3
B : Type u_5
inst✝² : Semiring R
inst✝¹ : SemilatticeSup B
inst✝ : OrderBot B
D : A → B
s : R[A]
hs : s.coeff.support.Nonempty
⊢ ↑(s.coeff.support.sup' hs D) = ↑(s.coeff.support.sup D)
Module: Mathlib.Algebra.Polynomial.Degree.Defs

Goal state before:
pp: R : Type u
inst✝ : Semiring R
c : R
⊢ (C c).nextCoeff = 0

Tactic:
rw [nextCoeff]
  simp

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

Goal state before:
pp: R : Type u
inst✝ : Semiring R
p : R[X]
⊢ (p ^ 0).degree ≤ 0 • p.degree

Tactic:
rw [pow_zero, zero_nsmul]; exact degree_one_le

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

Goal state before:
pp: R : Type u_1
A : Type u_3
B : Type u_5
inst✝³ : Semiring R
inst✝² : LinearOrder B
inst✝¹ : OrderBot B
p q : R[A]
D : A → B
inst✝ : AddZeroClass A
h : supDegree D p < supDegree D q
⊢ leadingCoeff D (p + q) = leadingCoeff D q

Tactic:
rw [add_comm, leadingCoeff_add_eq_left h]

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

Goal state before:
pp: R : Type u_1
A : Type u_3
B : Type u_5
inst✝³ : Semiring R
inst✝² : LinearOrder B
inst✝¹ : OrderBot B
D : A → B
ι : Type u_7
s : Finset ι
i : ι
f : ι → R[A]
inst✝ : AddZeroClass A
hi : i ∈ s
hmax : ∀ j ∈ s, j ≠ i → supDegree D (f j) < supDegree D (f i)
⊢ supDegree D (f i + ∑ x ∈ s.erase i, f x) = supDegree D (f i) ∧
    leadingCoeff D (f i + ∑ x ∈ s.erase i, f x) = leadingCoeff D (f i)

Tactic:
by_cases! hs : s.erase i = ∅

Goal state after:
case pos
R : Type u_1
A : Type u_3
B : Type u_5
inst✝³ : Semiring R
inst✝² : LinearOrder B
inst✝¹ : OrderBot B
D : A → B
ι : Type u_7
s : Finset ι
i : ι
f : ι → R[A]
inst✝ : AddZeroClass A
hi : i ∈ s
hmax : ∀ j ∈ s, j ≠ i → supDegree D (f j) < supDegree D (f i)
hs : s.erase i = ∅
⊢ supDegree D (f i + ∑ x ∈ s.erase i, f x) = supDegree D (f i) ∧
    leadingCoeff D (f i + ∑ x ∈ s.erase i, f x) = leadingCoeff D (f i)

case neg
R : Type u_1
A : Type u_3
B : Type u_5
inst✝³ : Semiring R
inst✝² : LinearOrder B
inst✝¹ : OrderBot B
D : A → B
ι : Type u_7
s : Finset ι
i : ι
f : ι → R[A]
inst✝ : AddZeroClass A
hi : i ∈ s
hmax : ∀ j ∈ s, j ≠ i → supDegree D (f j) < supDegree D (f i)
hs : (s.erase i).Nonempty
⊢ supDegree D (f i + ∑ x ∈ s.erase i, f x) = supDegree D (f i) ∧
    leadingCoeff D (f i + ∑ x ∈ s.erase i, f x) = leadingCoeff D (f i)
Module: Mathlib.Algebra.Polynomial.Eval.Coeff

Goal state before:
pp: R : Type u
inst✝ : Semiring R
p : R[X]
n : ℕ
x : R
⊢ eval₂ C X ((monomial n) x) = (monomial n) x

Tactic:
by
    rw [eval₂_monomial, ← smul_X_eq_monomial, C_mul']

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

Goal state before:
pp: R : Type u
inst✝¹ : Semiring R
S : Type u_1
inst✝ : Semiring S
f g : R[X] →+* S
h₁ : ∀ (a : R), f (C a) = g (C a)
h₂ : f X = g X
f' : AddMonoidAlgebra R ℕ →+* S := f.comp (toFinsuppIso R).symm.toRingHom
hf' : f' = f.comp (toFinsuppIso R).symm.toRingHom
g' : AddMonoidAlgebra R ℕ →+* S := g.comp (toFinsuppIso R).symm.toRingHom
hg' : g' = g.comp (toFinsuppIso R).symm.toRingHom
⊢ f = g

Tactic:
have A : f' = g' := by
    ext
    · simp [f', g', h₁, RingEquiv.toRingHom_eq_coe]
    simpa using! h₂

Goal state after:
R : Type u
inst✝¹ : Semiring R
S : Type u_1
inst✝ : Semiring S
f g : R[X] →+* S
h₁ : ∀ (a : R), f (C a) = g (C a)
h₂ : f X = g X
f' : AddMonoidAlgebra R ℕ →+* S := f.comp (toFinsuppIso R).symm.toRingHom
hf' : f' = f.comp (toFinsuppIso R).symm.toRingHom
g' : AddMonoidAlgebra R ℕ →+* S := g.comp (toFinsuppIso R).symm.toRingHom
hg' : g' = g.comp (toFinsuppIso R).symm.toRingHom
A : f' = g'
⊢ f = g
Module: Mathlib.Algebra.Polynomial.AlgebraMap

Goal state before:
pp: case pos
S : Type v
inst✝ : CommRing S
z p : S
f : S[X]
i : ℕ
dvd_eval : p ∣ (RingHom.id S) (f.coeff i) * z ^ i + ∑ x ∈ f.support.erase i, (RingHom.id S) (f.coeff x) * z ^ x
dvd_terms : ∀ (j : ℕ), j ≠ i → p ∣ f.coeff j * z ^ j
hi : i ∈ f.support
j : ℕ
⊢ j ∈ f.support.erase i → p ∣ (RingHom.id S) (f.coeff j) * z ^ j

Tactic:
hj

Goal state after:
case pos
S : Type v
inst✝ : CommRing S
z p : S
f : S[X]
i : ℕ
dvd_eval : p ∣ (RingHom.id S) (f.coeff i) * z ^ i + ∑ x ∈ f.support.erase i, (RingHom.id S) (f.coeff x) * z ^ x
dvd_terms : ∀ (j : ℕ), j ≠ i → p ∣ f.coeff j * z ^ j
hi : i ∈ f.support
j : ℕ
hj : j ∈ f.support.erase i
⊢ p ∣ (RingHom.id S) (f.coeff j) * z ^ j
Module: Mathlib.Data.DFinsupp.Order

Goal state before:
pp: ι : Type u_1
α : ι → Type u_2
inst✝⁴ : (i : ι) → AddCommMonoid (α i)
inst✝³ : (i : ι) → PartialOrder (α i)
inst✝² : ∀ (i : ι), CanonicallyOrderedAdd (α i)
inst✝¹ : (i : ι) → Sub (α i)
inst✝ : ∀ (i : ι), OrderedSub (α i)
f g : Π₀ (i : ι), α i
⊢ ⇑(f - g) = ⇑f - ⇑g

Tactic:
ext i
  exact tsub_apply f g i

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

Goal state before:
pp: R : Type u
σ : Type u_1
inst✝ : CommSemiring R
m : σ →₀ ℕ
a : R
p : MvPolynomial σ R
⊢ coeff m (C a * p) = a * coeff m p

Tactic:
classical
  rw [mul_def, sum_C]
  · simp +contextual [sum_def, coeff_sum]
  simp

Goal state after:
Module: Mathlib.Data.DFinsupp.Lex

Goal state before:
pp: ι : Type u_1
α : ι → Type u_2
inst✝³ : LinearOrder ι
inst✝² : (i : ι) → AddMonoid (α i)
inst✝¹ : (i : ι) → LinearOrder (α i)
inst✝ : ∀ (i : ι), AddLeftStrictMono (α i)
x✝³ x✝² x✝¹ : Lex (Π₀ (i : ι), α i)
x✝ : x✝² < x✝¹
a : ι
lta : ∀ (j : ι), (fun x1 x2 ↦ x1 < x2) j a → (ofLex x✝²) j = (ofLex x✝¹) j
ha : (fun {i} ↦ (fun x x1 x2 ↦ x1 < x2) i) ((ofLex x✝²) a) ((ofLex x✝¹) a)
⊢ (fun {i} ↦ (fun x x1 x2 ↦ x1 < x2) i) ((ofLex (x✝³ + x✝²)) a) ((ofLex (x✝³ + x✝¹)) a)

Tactic:
by dsimp; gcongr

Goal state after:
Module: Mathlib.Data.DFinsupp.Lex

Goal state before:
pp: ι : Type u_1
α : ι → Type u_2
inst✝³ : LinearOrder ι
inst✝² : (i : ι) → AddMonoid (α i)
inst✝¹ : (i : ι) → LinearOrder (α i)
inst✝ : ∀ (i : ι), AddRightStrictMono (α i)
f x✝² x✝¹ : Lex (Π₀ (i : ι), α i)
x✝ : x✝² < x✝¹
a : ι
lta : ∀ (j : ι), (fun x1 x2 ↦ x1 < x2) j a → (ofLex x✝²) j = (ofLex x✝¹) j
ha : (fun {i} ↦ (fun x x1 x2 ↦ x1 < x2) i) ((ofLex x✝²) a) ((ofLex x✝¹) a)
⊢ (fun {i} ↦ (fun x x1 x2 ↦ x1 < x2) i) ((ofLex (Function.swap (fun x1 x2 ↦ x1 + x2) f x✝²)) a)
    ((ofLex (Function.swap (fun x1 x2 ↦ x1 + x2) f x✝¹)) a)

Tactic:
by dsimp; gcongr

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

Goal state before:
pp: R : Type u
σ : Type u_1
τ : Type u_2
inst✝ : CommSemiring R
f : σ → τ
φ : MvPolynomial σ R
i : τ
x : σ →₀ ℕ
hx : coeff x φ ≠ 0
hd : coeff (Finsupp.mapDomain f x) ((rename f) φ) ≠ 0
hi : ∀ a ∈ φ.degrees, f a ≠ i
j : σ
⊢ j ∈ x.support → (Finsupp.single (f j) (x j)) i = 0

Tactic:
hj

Goal state after:
R : Type u
σ : Type u_1
τ : Type u_2
inst✝ : CommSemiring R
f : σ → τ
φ : MvPolynomial σ R
i : τ
x : σ →₀ ℕ
hx : coeff x φ ≠ 0
hd : coeff (Finsupp.mapDomain f x) ((rename f) φ) ≠ 0
hi : ∀ a ∈ φ.degrees, f a ≠ i
j : σ
hj : j ∈ x.support
⊢ (Finsupp.single (f j) (x j)) i = 0
Module: Mathlib.Algebra.MvPolynomial.Degrees

Goal state before:
pp: R : Type u
σ : Type u_1
inst✝ : CommSemiring R
i : σ
f : MvPolynomial σ R
m : σ →₀ ℕ
h_m : m ∈ f.support
⊢ m i ≤ degreeOf i f

Tactic:
rw [degreeOf_eq_sup i]
  apply Finset.le_sup h_m

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
f : R →+* S
g : σ → S
p : MvPolynomial σ R
hp : ∀ i ∈ p.vars, g i = 0
⊢ (eval₂Hom f g) p = f (constantCoeff p)

Tactic:
conv_lhs => rw [p.as_sum]

Goal state after:
R : Type u
S : Type v
σ : Type u_1
inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
f : R →+* S
g : σ → S
p : MvPolynomial σ R
hp : ∀ i ∈ p.vars, g i = 0
⊢ (eval₂Hom f g) (∑ v ∈ p.support, (monomial v) (coeff v p)) = f (constantCoeff p)
Module: Mathlib.Algebra.MvPolynomial.Degrees

Goal state before:
pp: R : Type u
σ : Type u_1
inst✝ : CommSemiring R
p q : MvPolynomial σ R
hp : ¬p = 0
b : σ →₀ ℕ
hb₁ : b ∈ p.support
hb₂ : (p.support.sup fun m ↦ (toMultiset m).card) = (toMultiset b).card
h : b ∈ q.support
⊢ (toMultiset b).card ≤ q.support.sup fun m ↦ (toMultiset m).card

Tactic:
apply Finset.le_sup h

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

Goal state before:
pp: case pos
R : Type u
σ : Type u_1
inst✝³ : CommSemiring R
S : Type u_2
subS : Type u_3
inst✝² : CommSemiring S
inst✝¹ : SetLike subS S
inst✝ : SubsemiringClass subS S
f✝ : R →+* S
s : subS
v : σ → S
hv : ∀ (i : σ), v i ∈ s
a : σ →₀ ℕ
b : R
f : MvPolynomial σ R
ha : a ∉ f.coeff.support
a✝ : b ≠ 0
ih : (∀ (i : σ →₀ ℕ), f✝ (coeff i f) ∈ s) → eval₂ f✝ v f ∈ s
hs : ∀ (i : σ →₀ ℕ), f✝ (coeff i ((monomial a) b + f)) ∈ s
i : σ →₀ ℕ
h : a = i
this : f✝ (b + coeff i f) ∈ s
⊢ f✝ (coeff i f) ∈ s

pp: case neg
R : Type u
σ : Type u_1
inst✝³ : CommSemiring R
S : Type u_2
subS : Type u_3
inst✝² : CommSemiring S
inst✝¹ : SetLike subS S
inst✝ : SubsemiringClass subS S
f✝ : R →+* S
s : subS
v : σ → S
hv : ∀ (i : σ), v i ∈ s
a : σ →₀ ℕ
b : R
f : MvPolynomial σ R
ha : a ∉ f.coeff.support
a✝ : b ≠ 0
ih : (∀ (i : σ →₀ ℕ), f✝ (coeff i f) ∈ s) → eval₂ f✝ v f ∈ s
hs : ∀ (i : σ →₀ ℕ), f✝ (coeff i ((monomial a) b + f)) ∈ s
i : σ →₀ ℕ
h : ¬a = i
this : f✝ (0 + coeff i f) ∈ s
⊢ f✝ (coeff i f) ∈ s

Tactic:
· subst h
      rw [MvPolynomial.notMem_support_iff.1 ha, map_zero]
      exact zero_mem _

Goal state after:
case neg
R : Type u
σ : Type u_1
inst✝³ : CommSemiring R
S : Type u_2
subS : Type u_3
inst✝² : CommSemiring S
inst✝¹ : SetLike subS S
inst✝ : SubsemiringClass subS S
f✝ : R →+* S
s : subS
v : σ → S
hv : ∀ (i : σ), v i ∈ s
a : σ →₀ ℕ
b : R
f : MvPolynomial σ R
ha : a ∉ f.coeff.support
a✝ : b ≠ 0
ih : (∀ (i : σ →₀ ℕ), f✝ (coeff i f) ∈ s) → eval₂ f✝ v f ∈ s
hs : ∀ (i : σ →₀ ℕ), f✝ (coeff i ((monomial a) b + f)) ∈ s
i : σ →₀ ℕ
h : ¬a = i
this : f✝ (0 + coeff i f) ∈ s
⊢ f✝ (coeff i f) ∈ s
Module: Mathlib.Algebra.Polynomial.Degree.Lemmas

Goal state before:
pp: R : Type u
a : R
inst✝ : Semiring R
p : R[X]
h : a * p.leadingCoeff ≠ 0
⊢ (C a * p).degree = p.degree

Tactic:
degree_mul' (by simpa)

Goal state after:
R : Type u
a : R
inst✝ : Semiring R
p : R[X]
h : a * p.leadingCoeff ≠ 0
⊢ (C a).degree + p.degree = p.degree
Module: Mathlib.Algebra.Polynomial.Degree.TrailingDegree

Goal state before:
pp: R : Type u
inst✝ : Semiring R
p q : R[X]
n : ℕ
hn : ∑ x ∈ antidiagonal n, p.coeff x.1 * q.coeff x.2 ≠ 0
i j : ℕ
hij : (i, j) ∈ antidiagonal n
hpq : p.coeff (i, j).1 * q.coeff (i, j).2 ≠ 0
⊢ p.trailingDegree + q.trailingDegree ≤ ↑n

Tactic:
refine
    (add_le_add (min_le (mem_support_iff.mpr (left_ne_zero_of_mul hpq)))
          (min_le (mem_support_iff.mpr (right_ne_zero_of_mul hpq)))).trans_eq ?_

Goal state after:
R : Type u
inst✝ : Semiring R
p q : R[X]
n : ℕ
hn : ∑ x ∈ antidiagonal n, p.coeff x.1 * q.coeff x.2 ≠ 0
i j : ℕ
hij : (i, j) ∈ antidiagonal n
hpq : p.coeff (i, j).1 * q.coeff (i, j).2 ≠ 0
⊢ ↑(i, j).1 + ↑(i, j).2 = ↑n
Module: Mathlib.Algebra.Polynomial.Reverse

Goal state before:
pp: case ofFinsupp
R : Type u_1
inst✝ : Semiring R
N : ℕ
toFinsupp✝ : AddMonoidAlgebra R ℕ
a✝ : ℕ
⊢ a✝ ∈ (reflect N { toFinsupp := toFinsupp✝ }).support ↔ a✝ ∈ image ⇑(revAt N) { toFinsupp := toFinsupp✝ }.support

Tactic:
simp [reflect]

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

Goal state before:
pp: R : Type u_1
inst✝ : Semiring R
N : ℕ
f : R[X]
⊢ reflect N f = 0 ↔ f = 0

Tactic:
simp [reflect]

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

Goal state before:
pp: case neg
R : Type u_1
inst✝ : Semiring R
p q : R[X]
pq : p.degree < q.degree
n : ℕ
nd : ¬n = q.natDegree
⊢ (p + q).eraseLead.coeff n = (p + q.eraseLead).coeff n

Tactic:
rw [eraseLead_coeff, coeff_add, coeff_add, eraseLead_coeff, if_neg, if_neg nd]
    rintro rfl
    exact nd (natDegree_add_eq_right_of_degree_lt pq)

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

Goal state before:
pp: case neg
R : Type u_1
inst✝ : Semiring R
N O : ℕ
f : R[X]
Cf : #f.support ≤ Nat.succ 0
Nf : f.natDegree ≤ N
cg : ℕ
hcg : ∀ (g : R[X]), #g.support ≤ cg.succ → g.natDegree ≤ O → reflect (N + O) (f * g) = reflect N f * reflect O g
g : R[X]
Cg : #g.support ≤ (cg + 1).succ
Og : g.natDegree ≤ O
g0 : ¬g = 0
⊢ reflect N f * reflect O g.eraseLead + reflect (N + O) (f * (C g.leadingCoeff * X ^ g.natDegree)) =
    reflect N f * reflect O g.eraseLead + reflect N f * reflect O (C g.leadingCoeff * X ^ g.natDegree)

pp: case neg.Cg
R : Type u_1
inst✝ : Semiring R
N O : ℕ
f : R[X]
Cf : #f.support ≤ Nat.succ 0
Nf : f.natDegree ≤ N
cg : ℕ
hcg : ∀ (g : R[X]), #g.support ≤ cg.succ → g.natDegree ≤ O → reflect (N + O) (f * g) = reflect N f * reflect O g
g : R[X]
Cg : #g.support ≤ (cg + 1).succ
Og : g.natDegree ≤ O
g0 : ¬g = 0
⊢ #g.eraseLead.support ≤ cg.succ

pp: case neg.Og
R : Type u_1
inst✝ : Semiring R
N O : ℕ
f : R[X]
Cf : #f.support ≤ Nat.succ 0
Nf : f.natDegree ≤ N
cg : ℕ
hcg : ∀ (g : R[X]), #g.support ≤ cg.succ → g.natDegree ≤ O → reflect (N + O) (f * g) = reflect N f * reflect O g
g : R[X]
Cg : #g.support ≤ (cg + 1).succ
Og : g.natDegree ≤ O
g0 : ¬g = 0
⊢ g.eraseLead.natDegree ≤ O

Tactic:
hcg

Goal state after:
case neg
R : Type u_1
inst✝ : Semiring R
N O : ℕ
f : R[X]
Cf : #f.support ≤ Nat.succ 0
Nf : f.natDegree ≤ N
cg : ℕ
hcg : ∀ (g : R[X]), #g.support ≤ cg.succ → g.natDegree ≤ O → reflect (N + O) (f * g) = reflect N f * reflect O g
g : R[X]
Cg : #g.support ≤ (cg + 1).succ
Og : g.natDegree ≤ O
g0 : ¬g = 0
⊢ reflect N f * reflect O g.eraseLead + reflect N f * reflect O (C g.leadingCoeff * X ^ g.natDegree) =
    reflect N f * reflect O g.eraseLead + reflect N f * reflect O (C g.leadingCoeff * X ^ g.natDegree)

case neg.Cg
R : Type u_1
inst✝ : Semiring R
N O : ℕ
f : R[X]
Cf : #f.support ≤ Nat.succ 0
Nf : f.natDegree ≤ N
cg : ℕ
hcg : ∀ (g : R[X]), #g.support ≤ cg.succ → g.natDegree ≤ O → reflect (N + O) (f * g) = reflect N f * reflect O g
g : R[X]
Cg : #g.support ≤ (cg + 1).succ
Og : g.natDegree ≤ O
g0 : ¬g = 0
⊢ #(C g.leadingCoeff * X ^ g.natDegree).support ≤ cg.succ

case neg.Og
R : Type u_1
inst✝ : Semiring R
N O : ℕ
f : R[X]
Cf : #f.support ≤ Nat.succ 0
Nf : f.natDegree ≤ N
cg : ℕ
hcg : ∀ (g : R[X]), #g.support ≤ cg.succ → g.natDegree ≤ O → reflect (N + O) (f * g) = reflect N f * reflect O g
g : R[X]
Cg : #g.support ≤ (cg + 1).succ
Og : g.natDegree ≤ O
g0 : ¬g = 0
⊢ (C g.leadingCoeff * X ^ g.natDegree).natDegree ≤ O

case neg.Cg
R : Type u_1
inst✝ : Semiring R
N O : ℕ
f : R[X]
Cf : #f.support ≤ Nat.succ 0
Nf : f.natDegree ≤ N
cg : ℕ
hcg : ∀ (g : R[X]), #g.support ≤ cg.succ → g.natDegree ≤ O → reflect (N + O) (f * g) = reflect N f * reflect O g
g : R[X]
Cg : #g.support ≤ (cg + 1).succ
Og : g.natDegree ≤ O
g0 : ¬g = 0
⊢ #g.eraseLead.support ≤ cg.succ

case neg.Og
R : Type u_1
inst✝ : Semiring R
N O : ℕ
f : R[X]
Cf : #f.support ≤ Nat.succ 0
Nf : f.natDegree ≤ N
cg : ℕ
hcg : ∀ (g : R[X]), #g.support ≤ cg.succ → g.natDegree ≤ O → reflect (N + O) (f * g) = reflect N f * reflect O g
g : R[X]
Cg : #g.support ≤ (cg + 1).succ
Og : g.natDegree ≤ O
g0 : ¬g = 0
⊢ g.eraseLead.natDegree ≤ O
Module: Mathlib.Algebra.MvPolynomial.Equiv

Goal state before:
pp: σ : Type u_1
R : Type u_2
S : Type u_3
inst✝² : CommSemiring R
inst✝¹ : CommSemiring S
inst✝ : Unique σ
f : MvPolynomial σ R
φ : R →+* S
a : S
⊢ Polynomial.eval₂ φ a ((uniqueAlgEquiv R σ) f) = eval₂ φ (fun x ↦ a) f

Tactic:
← eval₂_uniqueAlgEquiv

Goal state after:
σ : Type u_1
R : Type u_2
S : Type u_3
inst✝² : CommSemiring R
inst✝¹ : CommSemiring S
inst✝ : Unique σ
f : MvPolynomial σ R
φ : R →+* S
a : S
⊢ Polynomial.eval₂ φ a ((uniqueAlgEquiv R σ) f) = Polynomial.eval₂ φ a ((uniqueAlgEquiv R σ) f)
Module: Mathlib.Algebra.MvPolynomial.Equiv

Goal state before:
pp: R : Type u
S₁ : Type v
inst✝ : CommSemiring R
m : Option S₁ →₀ ℕ
r : R
⊢ (optionEquivLeft R S₁) ((monomial m) r) = (Polynomial.monomial (m none)) ((monomial m.some) r)

Tactic:
by
  rw [optionEquivLeft_apply, aeval_monomial, prod_option_index]
  · rw [MvPolynomial.monomial_eq, ← Polynomial.C_mul_X_pow_eq_monomial]
    simp only [Polynomial.algebraMap_apply, algebraMap_eq, Option.elim_none, Option.elim_some,
      map_mul, mul_assoc]
    simp only [mul_comm, map_finsuppProd, map_pow]
  · simp
  · intros; rw [pow_add]

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

Goal state before:
pp: R : Type u_2
inst✝² : Ring R
inst✝¹ : NoZeroDivisors R
inst✝ : Nontrivial R
x : R
P : R[X]
hx : x ≠ 0
h : P.nextCoeff = 0
hp : ¬P = 0
he : ¬P.eraseLead = 0
h₁ : ((X - C x) * P).natDegree = P.natDegree + 1
dP : ℕ
hdP : P.natDegree = dP + 2
h₂ : ((X - C x) * P).nextCoeff ≠ 0
n : ℕ
hn : n ≥ P.natDegree
⊢ ((X - C x) * P.eraseLead).natDegree < n

Tactic:
grw [natDegree_mul (X_sub_C_ne_zero x) he, natDegree_eraseLead_le_of_nextCoeff_eq_zero h]
      simpa [add_comm, hdP] using! hn

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

Goal state before:
pp: R : Type u
inst✝ : Semiring R
p q : R[X]
hq : q.Monic
hpq : (p * q).Monic
⊢ p.Monic

Tactic:
by
  contrapose hpq
  rw [Monic.def] at hpq ⊢
  rwa [leadingCoeff_mul_monic hq]

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

Goal state before:
pp: case hX.refine_1
R : Type u
inst✝ : CommSemiring R
n : ℕ
i : Fin (n + 1)
n✝ : ℕ
⊢ (↑(finSuccEquiv R n) (X 0)).coeff n✝ =
    ((eval₂Hom (Polynomial.C.comp C) fun i ↦ Fin.cases Polynomial.X (fun k ↦ Polynomial.C (X k)) i) (X 0)).coeff n✝

Tactic:
simp [optionEquivLeft_apply, finSuccEquiv]

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

Goal state before:
pp: case hX.refine_2
R : Type u
inst✝ : CommSemiring R
n : ℕ
i : Fin (n + 1)
n✝ : ℕ
⊢ ∀ (i : Fin n),
    (↑(finSuccEquiv R n) (X i.succ)).coeff n✝ =
      ((eval₂Hom (Polynomial.C.comp C) fun i ↦ Fin.cases Polynomial.X (fun k ↦ Polynomial.C (X k)) i) (X i.succ)).coeff
        n✝

Tactic:
simp [optionEquivLeft_apply, finSuccEquiv]

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

Goal state before:
pp: case pos
R : Type u_1
inst✝ : Semiring R
f : R[X]
hf : f.natDegree = 0
⊢ f.coeff ((revAt f.natDegree) 1) = 0

pp: case neg
R : Type u_1
inst✝ : Semiring R
f : R[X]
hf : ¬f.natDegree = 0
⊢ f.coeff ((revAt f.natDegree) 1) = f.coeff (f.natDegree - 1)

Tactic:
· have : coeff f 1 = 0 := coeff_eq_zero_of_natDegree_lt (by simp only [hf, zero_lt_one])
    simp [*, revAt]

Goal state after:
case neg
R : Type u_1
inst✝ : Semiring R
f : R[X]
hf : ¬f.natDegree = 0
⊢ f.coeff ((revAt f.natDegree) 1) = f.coeff (f.natDegree - 1)
Module: Mathlib.Algebra.Polynomial.Reverse

Goal state before:
pp: R : Type u_1
inst✝ : Ring R
f : R[X]
⊢ -reflect (-f).natDegree f = -reflect f.natDegree f

Tactic:
natDegree_neg

Goal state after:
R : Type u_1
inst✝ : Ring R
f : R[X]
⊢ -reflect f.natDegree f = -reflect f.natDegree f