(adsbygoogle = window.adsbygoogle || []).push({}); Ok; this is another thread that covers two questions. I didn't want to mix them with my previous post; it's from the same 'section' but the questions are different. If any mods have issues with this, please say so.

1) If [tex]R \cup S[/tex] is reflexive, then either R is reflexive or S is reflexive.

* I see this as false; If there's some (x,x) such that xRx in R, then since R is in [tex]R \cup S[/tex] that relation must also be in S. So they would both have to be reflexive. My question, I don't think this is enough of an explaination; and I don't even know if it's right. If anybody could help me out, that would be great.

2) If [tex]R \cap S[/tex] is reflexive, then both R is reflexive and S is reflexive.

* True, since your talking about the intersection of R and S. If x is related to x in R, then this must also hold true for S since x would also be an element in S, and therefore related to x. I think I'm hitting something close to the answer... But I'm not sure.

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# Homework Help: [Discrete Math] Relations, (R subset S) / (R Intersects S)

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