Recent content by Paparazzi

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    Is the Set of Integers Closed in the Euclidean Plane?

    Again, the textbook has not mentioned sequences yet, so they cannot be used to solve the problem. I am also not looking for any other way to solve it other than directly, because I am fairly certain that it can be done so, and that is an exercise that I have created for myself to make sure that...
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    Is the Set of Integers Closed in the Euclidean Plane?

    I just realized while walking from the library that nothing I typed made any sense whatsoever, since I made no hypothesis about n being a limit point. Actually I think it made sense, but had nothing to do with the question, and therefore made zero sense within the context of this question.
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    Is the Set of Integers Closed in the Euclidean Plane?

    Oh I see. At this point in the textbook, he hasn't said anything other than the definition of a sequence itself. That's exactly what I was thinking as well. I do think I finally see where I was confused now. By vacuous truth, I showed that the set was closed, but that did nothing to show that...
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    Is the Set of Integers Closed in the Euclidean Plane?

    I'm a little confused how that is relevant to a direct proof of showing that the set of all integers is closed. Edit: Actually, if the statement is vacuously true, then it actually shows nothing at all, since then we could conclude nothing about the set of all integers, correct? Serves me right...
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    Is the Set of Integers Closed in the Euclidean Plane?

    When considered as a subset of \mathbb{R}^2, \mathbb{Z} is a closed set. Proof. We will show, by definition, that \mathbb{Z} \subset \mathbb{R}^2 is closed. That is, we need to show that, if n is a limit point of \mathbb{Z}, then n \in \mathbb{Z}. I think this becomes vacuously true, since our...
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    Finding the Right Delta for Epsilon-Delta Proofs

    That is exactly what I needed. Thank you so much!
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    Finding the Right Delta for Epsilon-Delta Proofs

    So since the statement is true for all \epsilon > 0, that's the reason you can just substitute in what is needed (since \epsilon/2 > 0)? Thanks a bunch for the reply.
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    Finding the Right Delta for Epsilon-Delta Proofs

    Homework Statement Suppose the functions f and g satisfy the following property: for all \epsilon > 0 and all x, \text{if } 0 < | x - 2 | < \text{sin}^2(\frac{\epsilon^2}{9}) + \epsilon, \text{then } | f(x) - 2 | < \epsilon. \text{if } 0 < | x - 2 | < \epsilon^2, \text{then } | g(x) - 4 | <...
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    Can Probability and Topology Combine for an Exciting Research Topic?

    I need to write a paper on something to do with (general) topology, and we are encouraged to try and relate it to something that we enjoy. I really like probability (at least basic probability + stochastic processes), and I'm wondering if someone might suggest topic(s) that might be of interest...
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