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Can sets be bounded by infinity?

  1. Jan 27, 2009 #1
    I cannot remember if infinity is an upper bound for a subset of R?
    I think so, but I want to be sure before I use it in a proof.
  2. jcsd
  3. Jan 28, 2009 #2


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    Welcome to PF!

    Hi Magenta ! Welcome to PF! :smile:

    It depends what you mean by R.

    Infinity isn't usually a member of R, and if it isn't then it can't be an upper bound. :wink:
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