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Math Help - d(x/lnx) /dx

  1. #1
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    d(x/lnx) /dx

    Hi can anyone help please.

    Use standard results about differentiation to find f'(x) where f(x) = x / lnx
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  2. #2
    MHF Contributor harish21's Avatar
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    Quote Originally Posted by pasleycakes View Post
    Hi can anyone help please.

    Use standard results about differentiation to find f'(x) where f(x) = x / lnx
    You should know what quotient rule is! Try applying that rule.
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  3. #3
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    solved

    here is the result - 1/lnx-1/lnx^2

    to get the result use the rule : (u'v-uv')/v^2 where in this case u is x and v is lnx,this derivative is simple gl
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  4. #4
    MHF Contributor Unknown008's Avatar
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    Quote Originally Posted by goroner View Post
    here is the result - 1/lnx-1/lnx^2

    to get the result use the rule : (u'v-uv')/v^2 where in this case u is x and v is lnx,this derivative is simple gl
    I'd like to know the answer too, but is the answer you just gave correct?

    I mean, is ln x^2 = (ln x)^2

    Using the quotient rule, I know that I get:

    \frac{ln x - 1}{(ln x)^2}

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