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Question about open sets in [0,1]

  1. Apr 10, 2010 #1
    Isn't [0,1) open in [0,1]? I know it's not open in [itex]\mathbb R[/itex], but I sincerely hope it's open in [0,1].
     
  2. jcsd
  3. Apr 10, 2010 #2

    Hurkyl

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    Yes, it is. The easiest way to prove it is probably to find an open set in R whose intersection with [0,1] is [0,1).
     
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