Logical meaning of a sentence












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There is one question, which says, "Give an example of a separable space $left( X, mathscr{T} right)$ in which there is an uncountable set which does not contain any of its limit point".



Now, the last part, which says, "A set which does not contain any of its limit points" is a bit confusing. Is it equivalent to "No point in the set is a limit point of the set"?



The confusion arises because, maybe the set has no limit points at all (and hence no point of the set is a limit point) and then vacously, it contains all of its limit points (which is exact opposite of the statement).










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    1














    There is one question, which says, "Give an example of a separable space $left( X, mathscr{T} right)$ in which there is an uncountable set which does not contain any of its limit point".



    Now, the last part, which says, "A set which does not contain any of its limit points" is a bit confusing. Is it equivalent to "No point in the set is a limit point of the set"?



    The confusion arises because, maybe the set has no limit points at all (and hence no point of the set is a limit point) and then vacously, it contains all of its limit points (which is exact opposite of the statement).










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      1












      1








      1







      There is one question, which says, "Give an example of a separable space $left( X, mathscr{T} right)$ in which there is an uncountable set which does not contain any of its limit point".



      Now, the last part, which says, "A set which does not contain any of its limit points" is a bit confusing. Is it equivalent to "No point in the set is a limit point of the set"?



      The confusion arises because, maybe the set has no limit points at all (and hence no point of the set is a limit point) and then vacously, it contains all of its limit points (which is exact opposite of the statement).










      share|cite|improve this question













      There is one question, which says, "Give an example of a separable space $left( X, mathscr{T} right)$ in which there is an uncountable set which does not contain any of its limit point".



      Now, the last part, which says, "A set which does not contain any of its limit points" is a bit confusing. Is it equivalent to "No point in the set is a limit point of the set"?



      The confusion arises because, maybe the set has no limit points at all (and hence no point of the set is a limit point) and then vacously, it contains all of its limit points (which is exact opposite of the statement).







      general-topology logic






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      asked Nov 27 at 6:47









      Aniruddha Deshmukh

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          If a set has no limit points, then it simultaneously contains all its limit points and none of its limit points. There is no contradiction here, and that's exactly the kind of example I would look for. At least at first. Uncountable is tricky, though, so you may instead have to look for an example which has limit points but doesn't contain them.






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            0














            You are being asked to give an example of a separable space $X$ which has an uncountable subset $Y$ such that any limit point $y$ of $Y$ in $X$ has $y not in Y$. If $Y$ somehow had no limit points, you'd be done.






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              If a set has no limit points, then it simultaneously contains all its limit points and none of its limit points. There is no contradiction here, and that's exactly the kind of example I would look for. At least at first. Uncountable is tricky, though, so you may instead have to look for an example which has limit points but doesn't contain them.






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                3














                If a set has no limit points, then it simultaneously contains all its limit points and none of its limit points. There is no contradiction here, and that's exactly the kind of example I would look for. At least at first. Uncountable is tricky, though, so you may instead have to look for an example which has limit points but doesn't contain them.






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                  If a set has no limit points, then it simultaneously contains all its limit points and none of its limit points. There is no contradiction here, and that's exactly the kind of example I would look for. At least at first. Uncountable is tricky, though, so you may instead have to look for an example which has limit points but doesn't contain them.






                  share|cite|improve this answer












                  If a set has no limit points, then it simultaneously contains all its limit points and none of its limit points. There is no contradiction here, and that's exactly the kind of example I would look for. At least at first. Uncountable is tricky, though, so you may instead have to look for an example which has limit points but doesn't contain them.







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                  answered Nov 27 at 6:57









                  Arthur

                  110k7105186




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                      0














                      You are being asked to give an example of a separable space $X$ which has an uncountable subset $Y$ such that any limit point $y$ of $Y$ in $X$ has $y not in Y$. If $Y$ somehow had no limit points, you'd be done.






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                        0














                        You are being asked to give an example of a separable space $X$ which has an uncountable subset $Y$ such that any limit point $y$ of $Y$ in $X$ has $y not in Y$. If $Y$ somehow had no limit points, you'd be done.






                        share|cite|improve this answer
























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                          0






                          You are being asked to give an example of a separable space $X$ which has an uncountable subset $Y$ such that any limit point $y$ of $Y$ in $X$ has $y not in Y$. If $Y$ somehow had no limit points, you'd be done.






                          share|cite|improve this answer












                          You are being asked to give an example of a separable space $X$ which has an uncountable subset $Y$ such that any limit point $y$ of $Y$ in $X$ has $y not in Y$. If $Y$ somehow had no limit points, you'd be done.







                          share|cite|improve this answer












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                          share|cite|improve this answer










                          answered Nov 27 at 6:58









                          Patrick Stevens

                          28.4k52874




                          28.4k52874






























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