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Confusing limit problem

  1. Jun 9, 2009 #1
    1. The problem statement, all variables and given/known data
    lim[x→-2¯(from the left)] x+2/sqrt(x^2-4)

    2. Relevant equations

    3. The attempt at a solution
    When I attempted this question I felt that the solution was that this is undefined and when i put it into my ti-89 it said that too. My friend argues that it's actually zero as that's what the leftbound limit approaches graphically. I am curious now to know the answer to this one
  2. jcsd
  3. Jun 9, 2009 #2


    User Avatar

    Staff: Mentor

    Welcome to the PF. Can you use this:


  4. Jun 9, 2009 #3
    l'hopitals doesn't work, I already tried it, you still get a zero on the bottom.
  5. Jun 9, 2009 #4


    Staff: Mentor

    Maybe you do, but I don't. Can you show us your work using L'Hopital's rule?
  6. Jun 9, 2009 #5
    x^2-4 = (x-2)(x+2)
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