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Homework Help: Standard topology and discrete topology

  1. Mar 2, 2010 #1
    How to compare the topology on R generated by the subbasis S={[x,y)|x,y are rational}U{(x,y]|x,y rational} to the discrete topology on R?
  2. jcsd
  3. Mar 2, 2010 #2
    Well, what are the basic open sets in the discrete topology?

    Which of these are open in the topology generated by S and which aren't? (by the way, the topology generated by S is far from the standard topology)
  4. Mar 14, 2010 #3
    On any given set X the discrete topology is the whole power set of X. How are topologies on X related to the power set of X? I hope you get it.
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