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Homework Help: Need help on finding derivatives of logarithmic functions!

  1. Apr 21, 2005 #1

    jzq

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    These are the problems (Please, just point me in the right direction):

    [tex]y=x^{2}\ln(6x)[/tex]

    [tex]f(x)=x\ln(12x)[/tex]
     
  2. jcsd
  3. Apr 21, 2005 #2
    Do you know the derivative of ln(x)?
     
  4. Apr 21, 2005 #3

    jzq

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    1/x

    10 char
     
  5. Apr 21, 2005 #4
    The product rule -- d(uv)/dx = u'v + uv'
    [edit: sorry had the answers, didnt know he didnt want to know them]
     
    Last edited: Apr 21, 2005
  6. Apr 21, 2005 #5
    [tex] y = x^2ln(6x) [/tex]

    [tex] \frac{dy}{dx} = \frac{d(x^2ln(6x))}{dx} [/tex]

    which is of the form

    [tex] \frac{d(u(x)v(x))}{dx} = u\frac{dv}{dx} + v\frac{du}{dx} [/tex]

    Use the chain rule when necessary (in the logarithm).
     
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