English
The toSubmodule of the supremum over S equals the closure of the supremum of the submodules.
Русский
toSubmodule(sSup S) равно замыканию супа подмодулей.
LaTeX
$$$toSubmodule( sSup S ) = (\bigvee S).closure.toSubmodule$$$
Lean4
instance : CompleteSemilatticeSup (ClosedSubmodule R N)
where
le_sSup s a ha x hx := subset_closure <| Submodule.mem_iSup_of_mem _ <| Submodule.mem_iSup_of_mem ha hx
sSup_le s a h
x := by
rw [← ClosedSubmodule.closure_toSubmodule_eq (s := a)]
apply closure_mono
simp only [Submodule.coe_toAddSubmonoid, coe_toSubmodule]
intro y hy
simp only [SetLike.mem_coe, Submodule.mem_iSup] at hy
exact hy a fun b _ hz ↦ Submodule.mem_iSup _ |>.mp hz _ <| fun hb ↦ h b hb