calc
  _ ≃ (x^n)^0   := Rel.refl
  _ ≃ 1         := pow_zero
  _ ≃ x^0       := Rel.symm pow_zero
  _ ≃ x^(n * 0) := pow_substR (Rel.symm mul_zero)
ℕ : Type
inst✝¹¹ : Core ℕ
inst✝¹⁰ : Induction ℕ
inst✝⁹ : Addition ℕ
inst✝⁸ : Sign ℕ
inst✝⁷ : Multiplication ℕ
α : Type
mul : α → α → α
inst✝⁶ : EqvOp α
inst✝⁵ : OfNat α 1
inst✝⁴ : Exponentiation ℕ mul
inst✝³ : AA.Substitutive₂ (fun x x_1 => x * x_1) AA.tc (fun x x_1 => x ≃ x_1) fun x x_1 => x ≃ x_1
inst✝² : AA.Associative fun x x_1 => x * x_1
inst✝¹ : AA.Commutative fun x x_1 => x * x_1
inst✝ : AA.Identity 1 fun x x_1 => x * x_1
x : α
n m : ℕ
⊢ (x ^ n) ^ 0 ≃ x ^ (n * 0)
no goals