exact Rel.trans ‹n + d ≃ m₁› ‹m₁ ≃ m₂›
ℕ : Type
inst✝³ : Core ℕ
inst✝² : Induction ℕ
inst✝¹ : Addition ℕ
inst✝ : Sign ℕ
order_inst : Order ℕ
n m₁ m₂ : ℕ
x✝¹ : m₁ ≃ m₂
x✝ : n ≤ m₁
d : ℕ
h✝ : n + d ≃ m₁
⊢ n + d ≃ m₂
no goals