Theorem: MvPolynomial.IsHomogeneous.exists_eval_ne_zero_of_coeff_finSuccEquiv_ne_zero_aux
File: Mathlib/RingTheory/MvPolynomial/Homogeneous.lean

tactic: have hF₀ : F ≠ 0 := by contrapose! hFn; simp [hFn]
state_before: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
⊢ ∃ r, (eval r) F ≠ 0
state_after: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
⊢ ∃ r, (eval r) F ≠ 0

tactic: have hdeg : natDegree (finSuccEquiv R N F) < n + 1 := by
  linarith [natDegree_finSuccEquiv F, degreeOf_le_totalDegree F 0, hF.totalDegree hF₀]
state_before: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
⊢ ∃ r, (eval r) F ≠ 0
state_after: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
⊢ ∃ r, (eval r) F ≠ 0

tactic: use Fin.cons 1 0
state_before: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
⊢ ∃ r, (eval r) F ≠ 0
state_after: case h
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
⊢ (eval (Fin.cons 1 0)) F ≠ 0

tactic: have aux : ∀ i ∈ Finset.range n, constantCoeff ((finSuccEquiv R N F).coeff i) = 0 := by
  intro i hi
  rw [Finset.mem_range] at hi
  apply (hF.finSuccEquiv_coeff_isHomogeneous i (n-i) (by omega)).coeff_eq_zero
  simp only [degree, Finsupp.support_zero, Finsupp.coe_zero, Pi.zero_apply, Finset.sum_const_zero]
  omega
state_before: case h
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
⊢ (eval (Fin.cons 1 0)) F ≠ 0
state_after: case h
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
⊢ (eval (Fin.cons 1 0)) F ≠ 0

tactic: simp_rw [eval_eq_eval_mv_eval', eval_one_map, Polynomial.eval_eq_sum_range' hdeg,
  eval_zero, one_pow, mul_one, map_sum, Finset.sum_range_succ, Finset.sum_eq_zero aux, zero_add]
state_before: case h
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
⊢ (eval (Fin.cons 1 0)) F ≠ 0
state_after: case h
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
⊢ constantCoeff (((finSuccEquiv R N) F).coeff n) ≠ 0

tactic: contrapose! hFn
state_before: case h
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
⊢ constantCoeff (((finSuccEquiv R N) F).coeff n) ≠ 0
state_after: case h
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
⊢ ((finSuccEquiv R N) F).coeff n = 0

tactic: ext d
state_before: case h
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
⊢ ((finSuccEquiv R N) F).coeff n = 0
state_after: case h.a
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
⊢ coeff d (((finSuccEquiv R N) F).coeff n) = coeff d 0

tactic: rw [coeff_zero]
state_before: case h.a
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
⊢ coeff d (((finSuccEquiv R N) F).coeff n) = coeff d 0
state_after: case h.a
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
⊢ coeff d (((finSuccEquiv R N) F).coeff n) = 0

tactic: obtain rfl | hd := eq_or_ne d 0
state_before: case h.a
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
⊢ coeff d (((finSuccEquiv R N) F).coeff n) = 0
state_after: case h.a.inl
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
⊢ coeff 0 (((finSuccEquiv R N) F).coeff n) = 0

case h.a.inr
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
hd : d ≠ 0
⊢ coeff d (((finSuccEquiv R N) F).coeff n) = 0

tactic: contrapose! hFn
state_before: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
⊢ F ≠ 0
state_after: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : F = 0
⊢ ((finSuccEquiv R N) F).coeff n = 0

tactic: simp [hFn]
state_before: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : F = 0
⊢ ((finSuccEquiv R N) F).coeff n = 0
state_after: no goals

tactic: linarith [natDegree_finSuccEquiv F, degreeOf_le_totalDegree F 0, hF.totalDegree hF₀]
state_before: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
⊢ ((finSuccEquiv R N) F).natDegree < n + 1
state_after: no goals

tactic: intro i hi
state_before: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
⊢ ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
state_after: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
i : ℕ
hi : i ∈ Finset.range n
⊢ constantCoeff (((finSuccEquiv R N) F).coeff i) = 0

tactic: rw [Finset.mem_range] at hi
state_before: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
i : ℕ
hi : i ∈ Finset.range n
⊢ constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
state_after: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
i : ℕ
hi : i < n
⊢ constantCoeff (((finSuccEquiv R N) F).coeff i) = 0

tactic: apply (hF.finSuccEquiv_coeff_isHomogeneous i (n-i) (by omega)).coeff_eq_zero
state_before: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
i : ℕ
hi : i < n
⊢ constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
state_after: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
i : ℕ
hi : i < n
⊢ degree 0 ≠ n - i

tactic: simp only [degree, Finsupp.support_zero, Finsupp.coe_zero, Pi.zero_apply, Finset.sum_const_zero]
state_before: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
i : ℕ
hi : i < n
⊢ degree 0 ≠ n - i
state_after: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
i : ℕ
hi : i < n
⊢ 0 ≠ n - i

tactic: omega
state_before: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
i : ℕ
hi : i < n
⊢ 0 ≠ n - i
state_after: no goals

tactic: omega
state_before: σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hFn : ((finSuccEquiv R N) F).coeff n ≠ 0
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
i : ℕ
hi : i < n
⊢ i + (n - i) = n
state_after: no goals

tactic: apply hFn
state_before: case h.a.inl
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
⊢ coeff 0 (((finSuccEquiv R N) F).coeff n) = 0
state_after: no goals

tactic: contrapose! hd
state_before: case h.a.inr
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
hd : d ≠ 0
⊢ coeff d (((finSuccEquiv R N) F).coeff n) = 0
state_after: case h.a.inr
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
hd : coeff d (((finSuccEquiv R N) F).coeff n) ≠ 0
⊢ d = 0

tactic: ext i
state_before: case h.a.inr
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
hd : coeff d (((finSuccEquiv R N) F).coeff n) ≠ 0
⊢ d = 0
state_after: case h.a.inr.h
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
hd : coeff d (((finSuccEquiv R N) F).coeff n) ≠ 0
i : Fin N
⊢ d i = 0 i

tactic: rw [Finsupp.coe_zero, Pi.zero_apply]
state_before: case h.a.inr.h
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
hd : coeff d (((finSuccEquiv R N) F).coeff n) ≠ 0
i : Fin N
⊢ d i = 0 i
state_after: case h.a.inr.h
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
hd : coeff d (((finSuccEquiv R N) F).coeff n) ≠ 0
i : Fin N
⊢ d i = 0

tactic: by_cases hi : i ∈ d.support
state_before: case h.a.inr.h
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
hd : coeff d (((finSuccEquiv R N) F).coeff n) ≠ 0
i : Fin N
⊢ d i = 0
state_after: case pos
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
hd : coeff d (((finSuccEquiv R N) F).coeff n) ≠ 0
i : Fin N
hi : i ∈ d.support
⊢ d i = 0

case neg
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
hd : coeff d (((finSuccEquiv R N) F).coeff n) ≠ 0
i : Fin N
hi : i ∉ d.support
⊢ d i = 0

tactic: have := hF.finSuccEquiv_coeff_isHomogeneous n 0 (add_zero _) hd
state_before: case pos
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
hd : coeff d (((finSuccEquiv R N) F).coeff n) ≠ 0
i : Fin N
hi : i ∈ d.support
⊢ d i = 0
state_after: case pos
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
hd : coeff d (((finSuccEquiv R N) F).coeff n) ≠ 0
i : Fin N
hi : i ∈ d.support
this : (weightedDegree 1) d = 0
⊢ d i = 0

tactic: simp only [weightedDegree_apply, Pi.one_apply, smul_eq_mul, mul_one, Finsupp.sum] at this
state_before: case pos
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
hd : coeff d (((finSuccEquiv R N) F).coeff n) ≠ 0
i : Fin N
hi : i ∈ d.support
this : (weightedDegree 1) d = 0
⊢ d i = 0
state_after: case pos
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
hd : coeff d (((finSuccEquiv R N) F).coeff n) ≠ 0
i : Fin N
hi : i ∈ d.support
this : ∑ x ∈ d.support, d x = 0
⊢ d i = 0

tactic: rw [Finset.sum_eq_zero_iff_of_nonneg (fun _ _ ↦ zero_le')] at this
state_before: case pos
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
hd : coeff d (((finSuccEquiv R N) F).coeff n) ≠ 0
i : Fin N
hi : i ∈ d.support
this : ∑ x ∈ d.support, d x = 0
⊢ d i = 0
state_after: case pos
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
hd : coeff d (((finSuccEquiv R N) F).coeff n) ≠ 0
i : Fin N
hi : i ∈ d.support
this : ∀ i ∈ d.support, d i = 0
⊢ d i = 0

tactic: exact this i hi
state_before: case pos
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
hd : coeff d (((finSuccEquiv R N) F).coeff n) ≠ 0
i : Fin N
hi : i ∈ d.support
this : ∀ i ∈ d.support, d i = 0
⊢ d i = 0
state_after: no goals

tactic: simpa using hi
state_before: case neg
σ : Type u_1
τ : Type u_2
R : Type u_3
S : Type u_4
inst✝² inst✝¹ : CommSemiring R
inst✝ : CommSemiring S
φ ψ : MvPolynomial σ R
m n✝ N : ℕ
F : MvPolynomial (Fin N.succ) R
n : ℕ
hF : F.IsHomogeneous n
hF₀ : F ≠ 0
hdeg : ((finSuccEquiv R N) F).natDegree < n + 1
aux : ∀ i ∈ Finset.range n, constantCoeff (((finSuccEquiv R N) F).coeff i) = 0
hFn : constantCoeff (((finSuccEquiv R N) F).coeff n) = 0
d : Fin N →₀ ℕ
hd : coeff d (((finSuccEquiv R N) F).coeff n) ≠ 0
i : Fin N
hi : i ∉ d.support
⊢ d i = 0
state_after: no goals