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Homework Help: L'Hospital's Rule

  1. Jul 9, 2010 #1
    1. The problem statement, all variables and given/known data

    lim(x→2)(x^2+x-6)/(x-2)

    2. Relevant equations



    3. The attempt at a solution

    lim(x→2)(x^2+x-6)/(x-2)=lim(x→2)(d/dx(x^2+x-6))/(d/dx(x-2))=lim(x→2)(2x+1)/1=lim(x→2)(2x+1)=5

    Is this a right solution? I have never done such before, so I am not sure in my answer.
     
  2. jcsd
  3. Jul 9, 2010 #2

    Dick

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    Science Advisor
    Homework Helper

    It's fine if you've checked you have a 0/0 form to begin with. You could also factor x^2+x-6 and cancel the denominator to check.
     
  4. Jul 10, 2010 #3
    yeaa, it is a right way,absolutely.L'Hopital's Rule is for 0/0 and inf/inf.
     
  5. Jul 10, 2010 #4
    Thank you a lot, guys.
     
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