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Homework Help: Evaluating a DNE Limit

  1. Jan 25, 2012 #1
    1. The problem statement, all variables and given/known data
    Evaluate each limit. If the limit does not exist, so indicate.

    lim as X approaches -3 of (X3+3X2)/(X2+6X+9)


    2. Relevant equations

    n/a

    3. The attempt at a solution

    I know that the answer is supposed to be DNE, but everytime I try to calculate it, I can't get the answer to not exist...I think I may just be looking at it wrong. I keep getting 0/-18.
     
  2. jcsd
  3. Jan 25, 2012 #2

    vela

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    How are you getting -18 on the bottom?
     
  4. Jan 25, 2012 #3
    Oh I forgot that (-3)2 is positive 9, not negative 9. ok, so now I got 0/0. But isn't it supposed to be something like x/0? so that it is a DNE?
     
  5. Jan 25, 2012 #4

    vela

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    0/0 is an indeterminate form, so it's still possible for the limit not to exist.
     
  6. Jan 25, 2012 #5
    Ahhh ok, I got a little mixed up. I kept going with the equation and I got the DNE answer. Thank you so much for your help :) I just could not wrap my brain around this one :)
     
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