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Topic: Finding Counterexample's With Sets?
Replies: 4   Last Post: Sep 30, 2012 6:48 PM

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Posts: 17
From: Buffalo, NY
Registered: 9/30/12
Finding Counterexample's With Sets?
Posted: Sep 30, 2012 11:36 AM
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So I pretty much have had decent success in this entire Module I've been working on but proving counterexamples are still stumping me for some reason. I did a 120 question homework assignment and there's two questions I cannot figure out. Maybe somebody can assist me:

Let A, B, and C be sets.
(a.) Find a counterexample to the statement
A union(B intersects C)=(A union B)intersects C.

(b.) Without using a Venn diagram, prove that:
A union(B intersects C)=(A union B)intersects(A union C)

I tried pasting the symbols for union and intersect but they came up as "?" when I previewed the post. Now for some reason I get very confused when it comes time to creating a proof and a counterexample. I'll attach the assignment as well just in case you would like to see everything I'm working on in addition to my answers. If somebody can help me understand this better I would really appreciate it. Thank you.

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