English
The units of an ordered commutative monoid form an ordered commutative group.
Русский
Единицы упорядоченного коммутативного моноида образуют упорядоченную коммутативную группу.
LaTeX
$$$ \alpha^{\times} ext{ is an ordered abelian group} $$$
Lean4
/-- The units of an ordered commutative monoid form an ordered commutative group. -/
@[to_additive /-- The units of an ordered commutative additive monoid form an ordered commutative
additive group. -/
]
instance isOrderedMonoid [CommMonoid α] [PartialOrder α] [IsOrderedMonoid α] : IsOrderedMonoid αˣ :=
{ mul_le_mul_left := fun _ _ h _ => (mul_le_mul_left' (α := α) h _) }