α : Type u
inst✝³ : Group α
inst✝² : LinearOrder α
inst✝¹ : CovariantClass α α (fun x x_1 => x * x_1) fun x x_1 => x ≤ x_1
a b c : α
inst✝ : CovariantClass α α (swap fun x x_1 => x * x_1) fun x x_1 => x ≤ x_1
⊢ a * a ≤ b * b ↔ a ≤ b
α : Type u
inst✝³ : Group α
inst✝² : LinearOrder α
inst✝¹ : CovariantClass α α (fun x x_1 => x * x_1) fun x x_1 => x ≤ x_1
a b c : α
inst✝ : CovariantClass α α (swap fun x x_1 => x * x_1) fun x x_1 => x ≤ x_1
⊢ a / b ≤ a⁻¹ * b ↔ a ≤ b
rw [div_eq_mul_inv, mul_inv_le_inv_mul_iff]
no goals
α : Type u
inst✝³ : Group α
inst✝² : LinearOrder α
inst✝¹ : CovariantClass α α (fun x x_1 => x * x_1) fun x x_1 => x ≤ x_1
a b c : α
inst✝ : CovariantClass α α (swap fun x x_1 => x * x_1) fun x x_1 => x ≤ x_1
⊢ a * a ≤ b * b ↔ a ≤ b
exact
  ⟨fun h => not_lt.mp fun k => not_lt.mpr h (mul_lt_mul_of_lt_of_lt k k), fun h =>
    mul_le_mul' h h⟩