Largest and smallest D intersect E can be

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Homework Statement


Ok so I have D\cap[x_{0}-\epsilon,x_{0}+\epsilon]=E\cap[x_{0}-\epsilon,x_{0}+\epsilon].
I wnat to find the largest and smallest that D\capE can be.



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The Attempt at a Solution


For largest I got [x_{0}-\epsilon,x_{0}+\epsilon]. I feel good about that, but I'm not so sure about smallest. I was thinking x0.
 
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Ok, I just realized the smallest = \oslash, right?
 
kathrynag said:
Ok, I just realized the smallest = \oslash, right?

Right, if [x_0 - \epsilon, x_0 + \epsilon] is not a subset of D.
 
kathrynag said:
Ok, I just realized the smallest = \oslash, right?
Yes, which raises the question, "What was the problem, really?"
 
HallsofIvy said:
Yes, which raises the question, "What was the problem, really?"

It was a problem about accumulation points and proving there was a limit. I figured out the rest of the problem already. It was just that part.
 
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