-- Mathlib/LinearAlgebra/Eigenspace/Zero.lean
lemma not_hasEigenvalue_zero_tfae (φ : Module.End K M) :
    List.TFAE [
      ¬ Module.End.HasEigenvalue φ 0,
      ¬ IsRoot (minpoly K φ) 0,
      constantCoeff φ.charpoly ≠ 0,
      LinearMap.det φ ≠ 0,
      ker φ = ⊥,
      ∀ (m : M), φ m = 0 → m = 0 ]

Proof state:
K : Type u_2
M : Type u_3
inst✝³ : Field K
inst✝² : AddCommGroup M
inst✝¹ : Module K M
inst✝ : Module.Finite K M
φ : End K M
this :
  [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ¬⊥ < ker φ,
      ∀ (m : M), m ≠ 0 → φ m ≠ 0].TFAE
aux₁ : ∀ (m : M), m ≠ 0 → φ m ≠ 0 ↔ φ m = 0 → m = 0
⊢ ker φ = ⊥ ↔ ¬⊥ < ker φ

Tactic:
rw [bot_lt_iff_ne_bot, not_not]

Result:
no goals

Proof state:
K : Type u_2
M : Type u_3
inst✝³ : Field K
inst✝² : AddCommGroup M
inst✝¹ : Module K M
inst✝ : Module.Finite K M
φ : End K M
this :
  (List.map Not
      [φ.HasEigenvalue 0, (minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) = 0, LinearMap.det φ = 0, ⊥ < ker φ,
        ∃ m, m ≠ 0 ∧ φ m = 0]).TFAE
⊢ [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ker φ = ⊥,
      ∀ (m : M), φ m = 0 → m = 0].TFAE

Tactic:
dsimp only [List.map] at this

Result:
K : Type u_2
M : Type u_3
inst✝³ : Field K
inst✝² : AddCommGroup M
inst✝¹ : Module K M
inst✝ : Module.Finite K M
φ : End K M
this :
  [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, ¬constantCoeff (charpoly φ) = 0, ¬LinearMap.det φ = 0, ¬⊥ < ker φ,
      ¬∃ m, m ≠ 0 ∧ φ m = 0].TFAE
⊢ [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ker φ = ⊥,
      ∀ (m : M), φ m = 0 → m = 0].TFAE

Proof state:
K : Type u_2
M : Type u_3
inst✝³ : Field K
inst✝² : AddCommGroup M
inst✝¹ : Module K M
inst✝ : Module.Finite K M
φ : End K M
this :
  [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ¬⊥ < ker φ,
      ∀ (m : M), m ≠ 0 → φ m ≠ 0].TFAE
⊢ [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ker φ = ⊥,
      ∀ (m : M), φ m = 0 → m = 0].TFAE

Tactic:
have aux₁ : ∀ m, (m ≠ 0 → φ m ≠ 0) ↔ (φ m = 0 → m = 0) := by intro m; apply not_imp_not

Result:
K : Type u_2
M : Type u_3
inst✝³ : Field K
inst✝² : AddCommGroup M
inst✝¹ : Module K M
inst✝ : Module.Finite K M
φ : End K M
this :
  [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ¬⊥ < ker φ,
      ∀ (m : M), m ≠ 0 → φ m ≠ 0].TFAE
aux₁ : ∀ (m : M), m ≠ 0 → φ m ≠ 0 ↔ φ m = 0 → m = 0
⊢ [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ker φ = ⊥,
      ∀ (m : M), φ m = 0 → m = 0].TFAE

Proof state:
K : Type u_2
M : Type u_3
inst✝³ : Field K
inst✝² : AddCommGroup M
inst✝¹ : Module K M
inst✝ : Module.Finite K M
φ : End K M
this :
  [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, ¬constantCoeff (charpoly φ) = 0, ¬LinearMap.det φ = 0, ¬⊥ < ker φ,
      ¬∃ m, m ≠ 0 ∧ φ m = 0].TFAE
⊢ [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ker φ = ⊥,
      ∀ (m : M), φ m = 0 → m = 0].TFAE

Tactic:
push_neg at this

Result:
K : Type u_2
M : Type u_3
inst✝³ : Field K
inst✝² : AddCommGroup M
inst✝¹ : Module K M
inst✝ : Module.Finite K M
φ : End K M
this :
  [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ¬⊥ < ker φ,
      ∀ (m : M), m ≠ 0 → φ m ≠ 0].TFAE
⊢ [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ker φ = ⊥,
      ∀ (m : M), φ m = 0 → m = 0].TFAE

Proof state:
K : Type u_2
M : Type u_3
inst✝³ : Field K
inst✝² : AddCommGroup M
inst✝¹ : Module K M
inst✝ : Module.Finite K M
φ : End K M
this :
  [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ¬⊥ < ker φ,
      ∀ (m : M), m ≠ 0 → φ m ≠ 0].TFAE
aux₁ : ∀ (m : M), m ≠ 0 → φ m ≠ 0 ↔ φ m = 0 → m = 0
aux₂ : ker φ = ⊥ ↔ ¬⊥ < ker φ
⊢ [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ker φ = ⊥,
      ∀ (m : M), φ m = 0 → m = 0].TFAE

Tactic:
simpa only [aux₁, aux₂] using this

Result:
no goals

Proof state:
K : Type u_2
M : Type u_3
inst✝³ : Field K
inst✝² : AddCommGroup M
inst✝¹ : Module K M
inst✝ : Module.Finite K M
φ : End K M
this :
  [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ¬⊥ < ker φ,
      ∀ (m : M), m ≠ 0 → φ m ≠ 0].TFAE
⊢ ∀ (m : M), m ≠ 0 → φ m ≠ 0 ↔ φ m = 0 → m = 0

Tactic:
intro m

Result:
K : Type u_2
M : Type u_3
inst✝³ : Field K
inst✝² : AddCommGroup M
inst✝¹ : Module K M
inst✝ : Module.Finite K M
φ : End K M
this :
  [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ¬⊥ < ker φ,
      ∀ (m : M), m ≠ 0 → φ m ≠ 0].TFAE
m : M
⊢ m ≠ 0 → φ m ≠ 0 ↔ φ m = 0 → m = 0

Proof state:
K : Type u_2
M : Type u_3
inst✝³ : Field K
inst✝² : AddCommGroup M
inst✝¹ : Module K M
inst✝ : Module.Finite K M
φ : End K M
this :
  [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ¬⊥ < ker φ,
      ∀ (m : M), m ≠ 0 → φ m ≠ 0].TFAE
m : M
⊢ m ≠ 0 → φ m ≠ 0 ↔ φ m = 0 → m = 0

Tactic:
apply not_imp_not

Result:
no goals

Proof state:
K : Type u_2
M : Type u_3
inst✝³ : Field K
inst✝² : AddCommGroup M
inst✝¹ : Module K M
inst✝ : Module.Finite K M
φ : End K M
this :
  [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ¬⊥ < ker φ,
      ∀ (m : M), m ≠ 0 → φ m ≠ 0].TFAE
aux₁ : ∀ (m : M), m ≠ 0 → φ m ≠ 0 ↔ φ m = 0 → m = 0
⊢ [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ker φ = ⊥,
      ∀ (m : M), φ m = 0 → m = 0].TFAE

Tactic:
have aux₂ : ker φ = ⊥ ↔ ¬ ⊥ < ker φ := by rw [bot_lt_iff_ne_bot, not_not]

Result:
K : Type u_2
M : Type u_3
inst✝³ : Field K
inst✝² : AddCommGroup M
inst✝¹ : Module K M
inst✝ : Module.Finite K M
φ : End K M
this :
  [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ¬⊥ < ker φ,
      ∀ (m : M), m ≠ 0 → φ m ≠ 0].TFAE
aux₁ : ∀ (m : M), m ≠ 0 → φ m ≠ 0 ↔ φ m = 0 → m = 0
aux₂ : ker φ = ⊥ ↔ ¬⊥ < ker φ
⊢ [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ker φ = ⊥,
      ∀ (m : M), φ m = 0 → m = 0].TFAE

Proof state:
K : Type u_2
M : Type u_3
inst✝³ : Field K
inst✝² : AddCommGroup M
inst✝¹ : Module K M
inst✝ : Module.Finite K M
φ : End K M
⊢ [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ker φ = ⊥,
      ∀ (m : M), φ m = 0 → m = 0].TFAE

Tactic:
have := (hasEigenvalue_zero_tfae φ).not

Result:
K : Type u_2
M : Type u_3
inst✝³ : Field K
inst✝² : AddCommGroup M
inst✝¹ : Module K M
inst✝ : Module.Finite K M
φ : End K M
this :
  (List.map Not
      [φ.HasEigenvalue 0, (minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) = 0, LinearMap.det φ = 0, ⊥ < ker φ,
        ∃ m, m ≠ 0 ∧ φ m = 0]).TFAE
⊢ [¬φ.HasEigenvalue 0, ¬(minpoly K φ).IsRoot 0, constantCoeff (charpoly φ) ≠ 0, LinearMap.det φ ≠ 0, ker φ = ⊥,
      ∀ (m : M), φ m = 0 → m = 0].TFAE