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Andrew Gordon

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May 3, 2009, 3:35:05 AM5/3/09
to utexas-cs313k-spring2009
Maybe I don't understand some of this because it is so late, but can someone please provide a sample counterexample to one of the cells in the table? I don't really get what it wants us to show for that.

Thanks,
Andrew

Ian W.

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May 3, 2009, 10:16:13 AM5/3/09
to utexas-cs313k-spring2009
A counterexample for a particular relation R will be a pair <x,y> in
R, such that when you instantiate the particular property with <x,y>
it is false. For example, <3,3> in R=, and when we instantiate the
reflexivity property with <3,3>, we get (3 in N) -> (<3,3> in R=).
This example is not a counterexample, because the statement is true.

todd

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May 5, 2009, 1:07:01 AM5/5/09
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can you at least tell us how many properties are not true for a given
relation? lol
> > Andrew- Hide quoted text -
>
> - Show quoted text -

Ian W.

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May 5, 2009, 9:50:18 AM5/5/09
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Sure. The answer is... ooh, noo, wait, my internet is dying! I'll go
fix it, and finish writing this later. Probably around 3:30.

Bryan

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May 5, 2009, 9:55:52 AM5/5/09
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Quick, get this man some more trucks so that he may tell us the answer :o!
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