a✝ b✝ : ℤ
n : ℕ
a b : ℤ
⊢ natAbs a ≤ natAbs b ↔ ↑(natAbs a) ≤ ↑(natAbs b)
a✝ b✝ : ℤ
n : ℕ
a b : ℤ
⊢ natAbs a ≤ natAbs b ↔ a * a ≤ b * b
rw [← abs_le_iff_mul_self_le, abs_eq_natAbs, abs_eq_natAbs]
no goals
a✝ b✝ : ℤ
n : ℕ
a b : ℤ
⊢ natAbs a ≤ natAbs b ↔ ↑(natAbs a) ≤ ↑(natAbs b)
exact Int.ofNat_le.symm