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Homework Help: 2nd derivative

  1. Jan 22, 2009 #1
    1. The problem statement, all variables and given/known data
    What is the 2nd derivative of 3x - x(ln3)?

    2. Relevant equations

    3. The attempt at a solution
    I got this:
    f'(x) = 3x*ln3 -(ln3+x/3)
    f''(x) = 3x*ln3*ln3 -1/3 - 1/3
  2. jcsd
  3. Jan 22, 2009 #2
    How did you get the x/3 part? And in your second derivative, are you claiming that [tex]\frac{d}{dx} ln(3) = \frac{1}{3}[/tex]? You need to remember that ln(3) is a constant.
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