no goals
F : Type ?u.105789
α : Type u_1
β : Type ?u.105795
R : Type ?u.105798
inst✝¹ : Ring α
a b : α
n : ℕ
inst✝ : LinearOrder α
⊢ Odd (abs a) ↔ Odd a
cases' abs_choice a with h h <;> simp only [h, odd_neg]