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Homework Help: L'Hopital Rule - Limits

  1. Oct 24, 2012 #1
    1. The problem statement, all variables and given/known data
    http://puu.sh/1irk2 [Broken]


    2. Relevant equations



    3. The attempt at a solution
    I am having trouble doing this question. I tried doing the L'Hopital but didn't work. When I subbed in 0 in the function, I got 0/0.

    first time:
    I got that: http://puu.sh/1iroz [Broken]

    It still gave me the indeterminate form (0/0). Could someone give me a hint on solving this limit, I know the answer is 0 (used wolframalpha) but I am unsure why it is.

    Thanks
     
    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. Oct 24, 2012 #2

    lurflurf

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    Homework Helper

    Use L'Hopital's rulke again on the new limit.
     
  4. Oct 24, 2012 #3

    Dick

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    Science Advisor
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    Use algebra to simplify your answer. I don't think the limit is zero.
     
    Last edited by a moderator: May 6, 2017
  5. Oct 24, 2012 #4

    FOIWATER

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    Gold Member

    I also did not get zero

    I would not suggest using L'hospital's rule again, it can be simplified to give you a limit which is not zero I believe
     
  6. Oct 24, 2012 #5
    Nevermind, you are right. It is -1. I redid it, when I simplified it, all the x's that led to the evil division of zero disappeared.

    Thanks
     
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