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# Sets Help Watch

1. If someone could point me in the right direction on how to answer this, would be appreciated.
2. Well, if I were testing whether relation ~ is reflexive, I'd need to check that a~a for each element a in the set {1,2,3,4}. This would be the same as checking (a,a) is in the relation. So for example, is not reflexive because is not in the set (neither is 1,1). Similarly, if I want to check symmetric, I need to check that if a~b then b~a. So what I need to check is if (a,b) is in the set, is (b,a) in the set?
3. Lol thanks, really simple when I think about it.

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Updated: November 29, 2010
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