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Homework Help: Limit question

  1. Sep 28, 2011 #1
    Lim 1/x - 1/abs(x)
    x -->0-

    = 2/x

    as x approaches 0- , 2/x approaches neg infinity...

    why isnt this correct? the answer is does not exist.
  2. jcsd
  3. Sep 28, 2011 #2


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    What is the limit from the right?
  4. Sep 28, 2011 #3


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    That is right. "Infinity" is not a number. Saying that a limit is "infinity" or "negative infinity" is just saying that the limit does not exist for a particular reason.

    verty, the limit from the right is not relevant. The problem specifically asks for the limit from the left: [itex]\lim_{x\to 0^-}[/itex].
  5. Sep 28, 2011 #4


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    I apologise, I thought Mike was asking, why isn't this the limit, but he meant, why isn't this the one-sided limit.
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