Theorem: Associates.eq_pow_of_mul_eq_pow
File: Mathlib/RingTheory/UniqueFactorizationDomain.lean

tactic: by_cases hk0 : k = 0
state_before: α : Type u_1
inst✝² : CancelCommMonoidWithZero α
dec_irr : (p : Associates α) → Decidable (Irreducible p)
inst✝¹ : UniqueFactorizationMonoid α
dec : DecidableEq α
dec' : DecidableEq (Associates α)
inst✝ : Nontrivial α
a b c : Associates α
ha : a ≠ 0
hb : b ≠ 0
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
k : ℕ
h : a * b = c ^ k
⊢ ∃ d, a = d ^ k

tactic: use 1
state_before: case pos
α : Type u_1
inst✝² : CancelCommMonoidWithZero α
dec_irr : (p : Associates α) → Decidable (Irreducible p)
inst✝¹ : UniqueFactorizationMonoid α
dec : DecidableEq α
dec' : DecidableEq (Associates α)
inst✝ : Nontrivial α
a b c : Associates α
ha : a ≠ 0
hb : b ≠ 0
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
k : ℕ
h : a * b = c ^ k
hk0 : k = 0
⊢ ∃ d, a = d ^ k

tactic: rw [hk0, pow_zero] at h⊢
state_before: case pos
α : Type u_1
inst✝² : CancelCommMonoidWithZero α
dec_irr : (p : Associates α) → Decidable (Irreducible p)
inst✝¹ : UniqueFactorizationMonoid α
dec : DecidableEq α
dec' : DecidableEq (Associates α)
inst✝ : Nontrivial α
a b c : Associates α
ha : a ≠ 0
hb : b ≠ 0
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
k : ℕ
h : a * b = c ^ k
hk0 : k = 0
⊢ a = 1 ^ k

tactic: apply (mul_eq_one_iff.1 h).1
state_before: case pos
α : Type u_1
inst✝² : CancelCommMonoidWithZero α
dec_irr : (p : Associates α) → Decidable (Irreducible p)
inst✝¹ : UniqueFactorizationMonoid α
dec : DecidableEq α
dec' : DecidableEq (Associates α)
inst✝ : Nontrivial α
a b c : Associates α
ha : a ≠ 0
hb : b ≠ 0
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
k : ℕ
h : a * b = 1
hk0 : k = 0
⊢ a = 1

tactic: refine' is_pow_of_dvd_count ha _
state_before: case neg
α : Type u_1
inst✝² : CancelCommMonoidWithZero α
dec_irr : (p : Associates α) → Decidable (Irreducible p)
inst✝¹ : UniqueFactorizationMonoid α
dec : DecidableEq α
dec' : DecidableEq (Associates α)
inst✝ : Nontrivial α
a b c : Associates α
ha : a ≠ 0
hb : b ≠ 0
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
k : ℕ
h : a * b = c ^ k
hk0 : ¬k = 0
⊢ ∃ d, a = d ^ k

tactic: intro p hp
state_before: case neg
α : Type u_1
inst✝² : CancelCommMonoidWithZero α
dec_irr : (p : Associates α) → Decidable (Irreducible p)
inst✝¹ : UniqueFactorizationMonoid α
dec : DecidableEq α
dec' : DecidableEq (Associates α)
inst✝ : Nontrivial α
a b c : Associates α
ha : a ≠ 0
hb : b ≠ 0
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
k : ℕ
h : a * b = c ^ k
hk0 : ¬k = 0
⊢ ∀ (p : Associates α), Irreducible p → k ∣ count p (factors a)

tactic: apply dvd_count_of_dvd_count_mul hb hp hab
state_before: case neg
α : Type u_1
inst✝² : CancelCommMonoidWithZero α
dec_irr : (p : Associates α) → Decidable (Irreducible p)
inst✝¹ : UniqueFactorizationMonoid α
dec : DecidableEq α
dec' : DecidableEq (Associates α)
inst✝ : Nontrivial α
a b c : Associates α
ha : a ≠ 0
hb : b ≠ 0
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
k : ℕ
h : a * b = c ^ k
hk0 : ¬k = 0
p : Associates α
hp : Irreducible p
⊢ k ∣ count p (factors a)

tactic: rw [h]
state_before: case neg
α : Type u_1
inst✝² : CancelCommMonoidWithZero α
dec_irr : (p : Associates α) → Decidable (Irreducible p)
inst✝¹ : UniqueFactorizationMonoid α
dec : DecidableEq α
dec' : DecidableEq (Associates α)
inst✝ : Nontrivial α
a b c : Associates α
ha : a ≠ 0
hb : b ≠ 0
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
k : ℕ
h : a * b = c ^ k
hk0 : ¬k = 0
p : Associates α
hp : Irreducible p
⊢ k ∣ count p (factors (a * b))

tactic: apply dvd_count_pow _ hp
state_before: case neg
α : Type u_1
inst✝² : CancelCommMonoidWithZero α
dec_irr : (p : Associates α) → Decidable (Irreducible p)
inst✝¹ : UniqueFactorizationMonoid α
dec : DecidableEq α
dec' : DecidableEq (Associates α)
inst✝ : Nontrivial α
a b c : Associates α
ha : a ≠ 0
hb : b ≠ 0
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
k : ℕ
h : a * b = c ^ k
hk0 : ¬k = 0
p : Associates α
hp : Irreducible p
⊢ k ∣ count p (factors (c ^ k))

tactic: rintro rfl
state_before: α : Type u_1
inst✝² : CancelCommMonoidWithZero α
dec_irr : (p : Associates α) → Decidable (Irreducible p)
inst✝¹ : UniqueFactorizationMonoid α
dec : DecidableEq α
dec' : DecidableEq (Associates α)
inst✝ : Nontrivial α
a b c : Associates α
ha : a ≠ 0
hb : b ≠ 0
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
k : ℕ
h : a * b = c ^ k
hk0 : ¬k = 0
p : Associates α
hp : Irreducible p
⊢ c ≠ 0

tactic: rw [zero_pow' _ hk0] at h
state_before: α : Type u_1
inst✝² : CancelCommMonoidWithZero α
dec_irr : (p : Associates α) → Decidable (Irreducible p)
inst✝¹ : UniqueFactorizationMonoid α
dec : DecidableEq α
dec' : DecidableEq (Associates α)
inst✝ : Nontrivial α
a b : Associates α
ha : a ≠ 0
hb : b ≠ 0
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
k : ℕ
hk0 : ¬k = 0
p : Associates α
hp : Irreducible p
h : a * b = 0 ^ k
⊢ False

tactic: cases mul_eq_zero.mp h <;> contradiction
state_before: α : Type u_1
inst✝² : CancelCommMonoidWithZero α
dec_irr : (p : Associates α) → Decidable (Irreducible p)
inst✝¹ : UniqueFactorizationMonoid α
dec : DecidableEq α
dec' : DecidableEq (Associates α)
inst✝ : Nontrivial α
a b : Associates α
ha : a ≠ 0
hb : b ≠ 0
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
k : ℕ
hk0 : ¬k = 0
p : Associates α
hp : Irreducible p
h : a * b = 0
⊢ False