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Math Help - Finding the Limit by Interpreting an Expression as an Appropriate derivative

  1. #1
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    Finding the Limit by Interpreting an Expression as an Appropriate derivative

    Solved!
    Last edited by r2d2; November 19th 2009 at 01:02 PM.
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  2. #2
    MHF Contributor Calculus26's Avatar
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    f '(a) = lim [f(a+h)-f(a)]/h

    For yur problem note:


    ln[(3+h)/3] = ln(3+h) - ln(3)


    you have lim [ln(3+h) - ln(3)]/h

    What are f(x) and a?
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    Oh Right! Properties of the natural log : dividing turns into subtracting.

    'a' would be equal to 3 and the function be ln(x)?

    Then would I solve the derivative of ln(x) to get l/x, then plug in 3 for x?
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  4. #4
    MHF Contributor Calculus26's Avatar
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    you got it
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  5. #5
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    So when it says find the derivative, then answer would be 1/3.

    I just had to recognize the fact the I could change the ln function into the definition of a derivative. Thank you Sir!
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