Theorem: LO.FirstOrder.Arith.Model.mul_self_eq_one_iff (Arithmetization/Vorspiel/Lemmata.lean)

State before:
M : Type u_1
inst✝⁵ : Zero M
inst✝⁴ : One M
inst✝³ : Add M
inst✝² : Mul M
inst✝¹ : LT M
inst✝ : M ⊧ₘ* 𝐏𝐀⁻
a✝ b c a : M
⊢ ¬a * a = 1 ↔ ¬a = 1
Tactic:
simp [ne_iff_lt_or_gt]
State after:
no goals