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Math Help - [SOLVED] L'Hopital's Rule

  1. #1
    Junior Member
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    [SOLVED] L'Hopital's Rule

    limit x-->4 5/ln(x-3) - 5/(x-4)

    First, I put the two terms together then derived the top and bottom.
    d/dx((5x-20)-5ln(x-3)) / d/dx((x-4)ln(x-3))
    5-(5/(x-3)) / 1/(x-3)
    Then I derived it a second time and got:
    5/(x-3)^2 / -1/(x-3)^2

    Which gives me -5. Did I do this correctly? If not, could someone steer me in the right direction? Thank you, I appreciate your help.
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  2. #2
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    Check...

    Check your derivative of the denominator. It doesn't look right.
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  3. #3
    MHF Contributor Calculus26's Avatar
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    Not quite right --see attachment
    Attached Thumbnails Attached Thumbnails [SOLVED] L'Hopital's Rule-l-hopital1.jpg  
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  4. #4
    MHF Contributor Calculus26's Avatar
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    Make sure you see edited post--original had a small mistake
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