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Some Limits

  1. Jun 17, 2007 #1
    Hi, can somebody help me with this limit:

    The Problem Statement:

    limit as x approaches 1 from the left of ln(x(x-1)).

    Attempt

    I tried substitution and expansion in a Maclaurin series. This isn't homework its just a practice problem.
     
  2. jcsd
  3. Jun 17, 2007 #2

    morphism

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    What's [itex]\lim_{x->0^+} \ln x[/itex]?
     
  4. Jun 17, 2007 #3
    negative infinity
     
  5. Jun 17, 2007 #4

    morphism

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    And what happens when we write ln(x(x-1)) = ln(x) + ln(x-1)?
     
  6. Jun 17, 2007 #5
    thats ln(1)+negative infinity so the limit is still negative infinity innit?
     
  7. Jun 17, 2007 #6

    malawi_glenn

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    Yes. you can always confirm it by drawing the graph of the function on your Texas or Casio... or what you have
     
  8. Jun 17, 2007 #7

    VietDao29

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    Well, when x approaches 1 from the left, the expression isn't even defined in the real, since x - 1 < 0, and hence x (x - 1) < 0. So ln(x (x - 1)) is not defined.

    So, well, there's no limit from the left there. :)
     
  9. Jun 17, 2007 #8

    malawi_glenn

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    aaa from the left, lol, i also thought it was from the right;)
     
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