Power_Set_is_Closed_under_Union
Provedproofwikiset-theory
The power set is closed under union.
Preamble
import Mathlib.Analysis.Complex.Basic
Formal statement
theorem Power_Set_is_Closed_under_Union {α : Type _} (S : Set α) (A B : Set α) (hA : A ⊆ S) (hB : B ⊆ S) : A ∪ B ⊆ S := by sorrySource