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Finding the limit

  1. Oct 3, 2010 #1
    lim (2-x)/(x^2-4)

    Find the limit(is it exists)

    The substitution method failed so I factored the bottomto (x+2)(x-2).Where do I go from here?
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Oct 3, 2010 #2


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    Science Advisor

    A very important but often overlooked "law of limits":

    If f(x)= g(x) for all x except x= a, then [itex]\displaytype\lim_{x\to a}f(x)= \lim_{x\to a} g(x)[/itex].

    Here, for all x except x= 2, (2- x)/(x-2)(x+2)= -1/(x+2).
  4. Oct 3, 2010 #3
    use l'Hospital's rule
  5. Oct 3, 2010 #4
    Thank you
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