l3lab/ntp-mathlib huggingface dataset:
lemma dual_ne_zero :
    dual A K I ≠ 0 := by
  obtain ⟨b, hb, hb'⟩ := I.prop
  suffices algebraMap B L b ∈ dual A K I by
    intro e
    rw [e, mem_zero_iff, ← (algebraMap B L).map_zero,
      (IsIntegralClosure.algebraMap_injective B A L).eq_iff] at this
    exact mem_nonZeroDivisors_iff_ne_zero.mp hb this
  rw [mem_dual hI]
  intro a ha
  apply IsIntegrallyClosed.isIntegral_iff.mp
  

Proof state:
case intro.intro
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI : I ≠ 0
hJ : J ≠ 0
b : B
hb : b ∈ B⁰
hb' : ∀ b_1 ∈ ↑I, IsInteger B (b • b_1)
a : L
ha : a ∈ I
⊢ IsIntegral A (BilinForm.bilin (traceForm K L) ((algebraMap B L) b) a)

Next tactic:
apply isIntegral_trace
lemma dual_ne_zero :
    dual A K I ≠ 0 := by
  obtain ⟨b, hb, hb'⟩ := I.prop
  suffices algebraMap B L b ∈ dual A K I by
    intro e
    rw [e, mem_zero_iff, ← (algebraMap B L).map_zero,
      (IsIntegralClosure.algebraMap_injective B A L).eq_iff] at this
    exact mem_nonZeroDivisors_iff_ne_zero.mp hb this
  rw [mem_dual hI]
  intro a ha
  apply IsIntegrallyClosed.isIntegral_iff.mp
  apply isIntegral_trace
  

Proof state:
case intro.intro.hx
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI : I ≠ 0
hJ : J ≠ 0
b : B
hb : b ∈ B⁰
hb' : ∀ b_1 ∈ ↑I, IsInteger B (b • b_1)
a : L
ha : a ∈ I
⊢ IsIntegral A (((AlgHom.toLinearMap (lmul K L)) ((algebraMap B L) b)) a)

Next tactic:
dsimp
lemma dual_ne_zero :
    dual A K I ≠ 0 := by
  obtain ⟨b, hb, hb'⟩ := I.prop
  suffices algebraMap B L b ∈ dual A K I by
    intro e
    rw [e, mem_zero_iff, ← (algebraMap B L).map_zero,
      (IsIntegralClosure.algebraMap_injective B A L).eq_iff] at this
    exact mem_nonZeroDivisors_iff_ne_zero.mp hb this
  rw [mem_dual hI]
  intro a ha
  apply IsIntegrallyClosed.isIntegral_iff.mp
  apply isIntegral_trace
  dsimp
  

Proof state:
case intro.intro.hx
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI : I ≠ 0
hJ : J ≠ 0
b : B
hb : b ∈ B⁰
hb' : ∀ b_1 ∈ ↑I, IsInteger B (b • b_1)
a : L
ha : a ∈ I
⊢ IsIntegral A ((algebraMap B L) b * a)

Next tactic:
convert hb' a ha using 1
lemma dual_ne_zero :
    dual A K I ≠ 0 := by
  obtain ⟨b, hb, hb'⟩ := I.prop
  suffices algebraMap B L b ∈ dual A K I by
    intro e
    rw [e, mem_zero_iff, ← (algebraMap B L).map_zero,
      (IsIntegralClosure.algebraMap_injective B A L).eq_iff] at this
    exact mem_nonZeroDivisors_iff_ne_zero.mp hb this
  rw [mem_dual hI]
  intro a ha
  apply IsIntegrallyClosed.isIntegral_iff.mp
  apply isIntegral_trace
  dsimp
  convert hb' a ha using 1
  · 

Proof state:
case h.e
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI : I ≠ 0
hJ : J ≠ 0
b : B
hb : b ∈ B⁰
hb' : ∀ b_1 ∈ ↑I, IsInteger B (b • b_1)
a : L
ha : a ∈ I
⊢ IsIntegral A = IsInteger B

Next tactic:
ext w
lemma dual_ne_zero :
    dual A K I ≠ 0 := by
  obtain ⟨b, hb, hb'⟩ := I.prop
  suffices algebraMap B L b ∈ dual A K I by
    intro e
    rw [e, mem_zero_iff, ← (algebraMap B L).map_zero,
      (IsIntegralClosure.algebraMap_injective B A L).eq_iff] at this
    exact mem_nonZeroDivisors_iff_ne_zero.mp hb this
  rw [mem_dual hI]
  intro a ha
  apply IsIntegrallyClosed.isIntegral_iff.mp
  apply isIntegral_trace
  dsimp
  convert hb' a ha using 1
  · ext w
    

Proof state:
case h.e.h.a
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI : I ≠ 0
hJ : J ≠ 0
b : B
hb : b ∈ B⁰
hb' : ∀ b_1 ∈ ↑I, IsInteger B (b • b_1)
a : L
ha : a ∈ I
w : L
⊢ IsIntegral A w ↔ IsInteger B w

Next tactic:
exact IsIntegralClosure.isIntegral_iff (A := B)
lemma dual_ne_zero :
    dual A K I ≠ 0 := by
  obtain ⟨b, hb, hb'⟩ := I.prop
  suffices algebraMap B L b ∈ dual A K I by
    intro e
    rw [e, mem_zero_iff, ← (algebraMap B L).map_zero,
      (IsIntegralClosure.algebraMap_injective B A L).eq_iff] at this
    exact mem_nonZeroDivisors_iff_ne_zero.mp hb this
  rw [mem_dual hI]
  intro a ha
  apply IsIntegrallyClosed.isIntegral_iff.mp
  apply isIntegral_trace
  dsimp
  convert hb' a ha using 1
  · ext w
    exact IsIntegralClosure.isIntegral_iff (A := B)
  · 

Proof state:
case h.e'_1
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI : I ≠ 0
hJ : J ≠ 0
b : B
hb : b ∈ B⁰
hb' : ∀ b_1 ∈ ↑I, IsInteger B (b • b_1)
a : L
ha : a ∈ I
⊢ (algebraMap B L) b * a = b • a

Next tactic:
exact (Algebra.smul_def _ _).symm
lemma le_dual_inv_aux (hIJ : I * J ≤ 1) :
    J ≤ dual A K I := by
  

Proof state:
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI : I ≠ 0
hJ : J ≠ 0
hIJ : I * J ≤ 1
⊢ J ≤ dual A K I

Next tactic:
rw [dual, dif_neg hI]
lemma le_dual_inv_aux (hIJ : I * J ≤ 1) :
    J ≤ dual A K I := by
  rw [dual, dif_neg hI]
  

Proof state:
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI : I ≠ 0
hJ : J ≠ 0
hIJ : I * J ≤ 1
⊢ J ≤ { val := (↑I)ᵛ, property := (_ : IsFractional B⁰ (↑I)ᵛ) }

Next tactic:
intro x hx y hy
lemma le_dual_inv_aux (hIJ : I * J ≤ 1) :
    J ≤ dual A K I := by
  rw [dual, dif_neg hI]
  intro x hx y hy
  

Proof state:
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI : I ≠ 0
hJ : J ≠ 0
hIJ : I * J ≤ 1
x : L
hx : x ∈ (fun a => ↑a) J
y : L
hy : y ∈ restrictScalars A ↑I
⊢ BilinForm.bilin (traceForm K L) x y ∈ 1

Next tactic:
apply IsIntegrallyClosed.isIntegral_iff.mp
lemma le_dual_inv_aux (hIJ : I * J ≤ 1) :
    J ≤ dual A K I := by
  rw [dual, dif_neg hI]
  intro x hx y hy
  apply IsIntegrallyClosed.isIntegral_iff.mp
  

Proof state:
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI : I ≠ 0
hJ : J ≠ 0
hIJ : I * J ≤ 1
x : L
hx : x ∈ (fun a => ↑a) J
y : L
hy : y ∈ restrictScalars A ↑I
⊢ IsIntegral A (BilinForm.bilin (traceForm K L) x y)

Next tactic:
apply isIntegral_trace
lemma le_dual_inv_aux (hIJ : I * J ≤ 1) :
    J ≤ dual A K I := by
  rw [dual, dif_neg hI]
  intro x hx y hy
  apply IsIntegrallyClosed.isIntegral_iff.mp
  apply isIntegral_trace
  

Proof state:
case hx
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI : I ≠ 0
hJ : J ≠ 0
hIJ : I * J ≤ 1
x : L
hx : x ∈ (fun a => ↑a) J
y : L
hy : y ∈ restrictScalars A ↑I
⊢ IsIntegral A (((AlgHom.toLinearMap (lmul K L)) x) y)

Next tactic:
rw [IsIntegralClosure.isIntegral_iff (A := B)]
lemma le_dual_inv_aux (hIJ : I * J ≤ 1) :
    J ≤ dual A K I := by
  rw [dual, dif_neg hI]
  intro x hx y hy
  apply IsIntegrallyClosed.isIntegral_iff.mp
  apply isIntegral_trace
  rw [IsIntegralClosure.isIntegral_iff (A := B)]
  

Proof state:
case hx
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI : I ≠ 0
hJ : J ≠ 0
hIJ : I * J ≤ 1
x : L
hx : x ∈ (fun a => ↑a) J
y : L
hy : y ∈ restrictScalars A ↑I
⊢ ∃ y_1, (algebraMap B L) y_1 = ((AlgHom.toLinearMap (lmul K L)) x) y

Next tactic:
have ⟨z, _, hz⟩ := hIJ (FractionalIdeal.mul_mem_mul hy hx)
lemma le_dual_inv_aux (hIJ : I * J ≤ 1) :
    J ≤ dual A K I := by
  rw [dual, dif_neg hI]
  intro x hx y hy
  apply IsIntegrallyClosed.isIntegral_iff.mp
  apply isIntegral_trace
  rw [IsIntegralClosure.isIntegral_iff (A := B)]
  have ⟨z, _, hz⟩ := hIJ (FractionalIdeal.mul_mem_mul hy hx)
  

Proof state:
case hx
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI : I ≠ 0
hJ : J ≠ 0
hIJ : I * J ≤ 1
x : L
hx : x ∈ (fun a => ↑a) J
y : L
hy : y ∈ restrictScalars A ↑I
z : B
left✝ : z ∈ ↑⊤
hz : (Algebra.linearMap B L) z = y * x
⊢ ∃ y_1, (algebraMap B L) y_1 = ((AlgHom.toLinearMap (lmul K L)) x) y

Next tactic:
rw [mul_comm] at hz
lemma le_dual_inv_aux (hIJ : I * J ≤ 1) :
    J ≤ dual A K I := by
  rw [dual, dif_neg hI]
  intro x hx y hy
  apply IsIntegrallyClosed.isIntegral_iff.mp
  apply isIntegral_trace
  rw [IsIntegralClosure.isIntegral_iff (A := B)]
  have ⟨z, _, hz⟩ := hIJ (FractionalIdeal.mul_mem_mul hy hx)
  rw [mul_comm] at hz
  

Proof state:
case hx
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI : I ≠ 0
hJ : J ≠ 0
hIJ : I * J ≤ 1
x : L
hx : x ∈ (fun a => ↑a) J
y : L
hy : y ∈ restrictScalars A ↑I
z : B
left✝ : z ∈ ↑⊤
hz : (Algebra.linearMap B L) z = x * y
⊢ ∃ y_1, (algebraMap B L) y_1 = ((AlgHom.toLinearMap (lmul K L)) x) y

Next tactic:
exact ⟨z, hz⟩
lemma one_le_dual_one :
    1 ≤ dual A K (1 : FractionalIdeal B⁰ L) :=
  le_dual_inv_aux A K one_ne_zero (by 

Proof state:
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI : I ≠ 0
hJ : J ≠ 0
⊢ 1 * 1 ≤ 1

Next tactic:
rw [one_mul]
lemma le_dual_iff :
    I ≤ dual A K J ↔ I * J ≤ dual A K 1 := by
  

Proof state:
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI : I ≠ 0
hJ : J ≠ 0
⊢ I ≤ dual A K J ↔ I * J ≤ dual A K 1

Next tactic:
by_cases hI : I = 0
lemma le_dual_iff :
    I ≤ dual A K J ↔ I * J ≤ dual A K 1 := by
  by_cases hI : I = 0
  · 

Proof state:
case pos
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI✝ : I ≠ 0
hJ : J ≠ 0
hI : I = 0
⊢ I ≤ dual A K J ↔ I * J ≤ dual A K 1

Next tactic:
simp [hI, zero_le]
lemma le_dual_iff :
    I ≤ dual A K J ↔ I * J ≤ dual A K 1 := by
  by_cases hI : I = 0
  · simp [hI, zero_le]
  

Proof state:
case neg
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI✝ : I ≠ 0
hJ : J ≠ 0
hI : ¬I = 0
⊢ I ≤ dual A K J ↔ I * J ≤ dual A K 1

Next tactic:
rw [← coe_le_coe, ← coe_le_coe, coe_mul, coe_dual A K hJ, coe_dual_one, le_traceDual]
lemma inv_le_dual :
    I⁻¹ ≤ dual A K I :=
  if hI : I = 0 then by 

Proof state:
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI✝ : I ≠ 0
hJ : J ≠ 0
hI : I = 0
⊢ I⁻¹ ≤ dual A K I

Next tactic:
simp [hI]
lemma dual_inv_le :
    (dual A K I)⁻¹ ≤ I := by
  

Proof state:
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI : I ≠ 0
hJ : J ≠ 0
⊢ (dual A K I)⁻¹ ≤ I

Next tactic:
by_cases hI : I = 0
lemma dual_inv_le :
    (dual A K I)⁻¹ ≤ I := by
  by_cases hI : I = 0; · 

Proof state:
case pos
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI✝ : I ≠ 0
hJ : J ≠ 0
hI : I = 0
⊢ (dual A K I)⁻¹ ≤ I

Next tactic:
simp [hI]
lemma dual_inv_le :
    (dual A K I)⁻¹ ≤ I := by
  by_cases hI : I = 0; · simp [hI]
  

Proof state:
case neg
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI✝ : I ≠ 0
hJ : J ≠ 0
hI : ¬I = 0
⊢ (dual A K I)⁻¹ ≤ I

Next tactic:
convert mul_right_mono ((dual A K I)⁻¹)
    (mul_left_mono I (inv_le_dual A K I)) using 1
lemma dual_inv_le :
    (dual A K I)⁻¹ ≤ I := by
  by_cases hI : I = 0; · simp [hI]
  convert mul_right_mono ((dual A K I)⁻¹)
    (mul_left_mono I (inv_le_dual A K I)) using 1
  · 

Proof state:
case h.e'_3
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI✝ : I ≠ 0
hJ : J ≠ 0
hI : ¬I = 0
⊢ (dual A K I)⁻¹ = (fun J => J * (dual A K I)⁻¹) ((fun x => I * x) I⁻¹)

Next tactic:
simp only [mul_inv_cancel hI, one_mul]
lemma dual_inv_le :
    (dual A K I)⁻¹ ≤ I := by
  by_cases hI : I = 0; · simp [hI]
  convert mul_right_mono ((dual A K I)⁻¹)
    (mul_left_mono I (inv_le_dual A K I)) using 1
  · simp only [mul_inv_cancel hI, one_mul]
  · 

Proof state:
case h.e'_4
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI✝ : I ≠ 0
hJ : J ≠ 0
hI : ¬I = 0
⊢ I = (fun J => J * (dual A K I)⁻¹) ((fun x => I * x) (dual A K I))

Next tactic:
simp only [mul_inv_cancel (dual_ne_zero A K (hI := hI)), mul_assoc, mul_one]
lemma dual_eq_mul_inv :
    dual A K I = dual A K 1 * I⁻¹ := by
  

Proof state:
A : Type u_1
K : Type u_2
L : Type u
B : Type u_3
inst✝¹⁹ : CommRing A
inst✝¹⁸ : Field K
inst✝¹⁷ : CommRing B
inst✝¹⁶ : Field L
inst✝¹⁵ : Algebra A K
inst✝¹⁴ : Algebra B L
inst✝¹³ : Algebra A B
inst✝¹² : Algebra K L
inst✝¹¹ : Algebra A L
inst✝¹⁰ : IsScalarTower A K L
inst✝⁹ : IsScalarTower A B L
inst✝⁸ : IsDomain A
inst✝⁷ : IsDomain B
inst✝⁶ : IsFractionRing A K
inst✝⁵ : IsIntegralClosure B A L
inst✝⁴ : IsFractionRing B L
inst✝³ : FiniteDimensional K L
inst✝² : IsSeparable K L
inst✝¹ : IsIntegrallyClosed A
inst✝ : IsDedekindDomain B
I J : FractionalIdeal B⁰ L
hI : I ≠ 0
hJ : J ≠ 0
⊢ dual A K I = dual A K 1 * I⁻¹

Next tactic:
by_cases hI : I = 0