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Simple question on limit

  1. Dec 27, 2006 #1
    Hello all,

    I don't understand why |h|/h will become -1 as h approches 0 from the left. I can see how the numerator becomes negative, as |x| = -x if x< 0, but shouldn't the denominator become negative also since h < 0 when we approach 0 from the left? So why isn't the answer -h/-h = 1?
  2. jcsd
  3. Dec 27, 2006 #2


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    Homework Helper

    The numerator is always positive. It's true that |x|=-x when x<0, but in that case -x>0, and |x|/x=-x/x=-1.
  4. Dec 27, 2006 #3


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    Staff Emeritus
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    You see wrong. Here, -x is positive.
  5. Dec 27, 2006 #4
    Okay I see. Thanks for the help!
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