no goals
α : Type u
inst✝³ : Group α
inst✝² : LT α
inst✝¹ : CovariantClass α α (fun x x_1 => x * x_1) fun x x_1 => x < x_1
inst✝ : CovariantClass α α (swap fun x x_1 => x * x_1) fun x x_1 => x < x_1
a✝ b✝ c d a b : α
⊢ a / b < a ↔ 1 < b
simp only [div_eq_mul_inv, mul_lt_iff_lt_one_left', Left.inv_lt_one_iff]