Klungo
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Homework Statement
(Title is wrong)
I was able to prove the similar [itex]\bigcup(F \cup G)=(\cup F)\bigcup(\cup G)[/itex] but I'm not to sure how to go about this one.
Let F and G be nonempty families of sets. Prove
[itex]\bigcap(F \cup G)=(\cap F)\bigcap(\cap G)[/itex]
2. The attempt at a solution
To prove [itex]\bigcap(F \cup G) \subset (\cap F)\bigcap(\cap G)[/itex],
let [itex]x \subset \bigcap(F \cup G)[/itex] be arbitrary. Clearly, [itex]x \in S[/itex] for some set [itex]S \subset \bigcap F \cup G[/itex] containing all common elements in [itex]F \cup G[/itex]. We have [itex]S \in F \cup G.[/itex]
Do I go by..
We have two cases: (only one needs to be proven really.)
Case 1: [itex]If S \in F[/itex], clearly [itex]S \subset \cup F[/itex]...
(I'm stuck here)
or Do I go by...
Suppose [itex]S \in F[/itex] and [itex]S \in G[/itex]. Clearly [itex]S \subset \cup F[/itex] and [itex]S \subset \cup G[/itex]. (I'm stuck here)
I'll try proving the converse and restart the proof since I misread the problem.
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