English
Localization preserves surjectivity: the localized map is surjective if the original map is.
Русский
Локализация сохраняет суръективность: локализованная карта суръективна если исходная суръективна.
LaTeX
$$$$ \operatorname{LocalizationPreserves}( \text{surjective} ). $$$$
Lean4
/-- `M⁻¹R →+* M⁻¹S` is surjective if `R →+* S` is surjective. -/
theorem surjective_localizationPreserves : LocalizationPreserves surjective :=
by
introv R H x
obtain ⟨x, ⟨_, s, hs, rfl⟩, rfl⟩ := IsLocalization.mk'_surjective (M.map f) x
obtain ⟨y, rfl⟩ := H x
use IsLocalization.mk' R' y ⟨s, hs⟩
rw [IsLocalization.map_mk']