Empty union
= Empty union
{title2=$\bigcup\varnothing=\varnothing$}
The <union> of an empty family of <sets> is the <empty set>: membership would require a member of that family containing the proposed <set element>, and there are no members.
= Empty union
{title2=$\bigcup\varnothing=\varnothing$}
The <union> of an empty family of <sets> is the <empty set>: membership would require a member of that family containing the proposed <set element>, and there are no members.