English
The embedding inl is strictly monotone if the embedding is injective.
Русский
Встраивание inl строго монотонно, если оно инъективно.
LaTeX
$$$\text{inl}$ строго монотонно.$$
Lean4
theorem inr_mono [GroupWithZero M₀] [Preorder M₀] [LinearOrderedCommGroupWithZero N₀]
[DecidablePred fun x : N₀ ↦ x = 0] : Monotone (inr M₀ N₀) :=
by
refine (WithZero.map'_mono MonoidHom.inr_mono).comp ?_
intro x y
obtain rfl | ⟨x, rfl⟩ := GroupWithZero.eq_zero_or_unit x <;>
obtain rfl | ⟨y, rfl⟩ := GroupWithZero.eq_zero_or_unit y <;>
· simp [WithZero.withZeroUnitsEquiv]