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Homework Help: Another differentiation question

  1. Mar 3, 2008 #1
    1. The problem statement, all variables and given/known data

    Supposed "f" is a differentiable function. Write the expression for the derivative of the following function.

    a) h(x) = -4x^3 * f(x)

    b) h(x) = 2/[tex]\sqrt{x}[/tex]* f(x)

    2. Relevant equations

    N/a

    3. The attempt at a solution

    Would the answers just be (using the product rule)

    a) h'(x) = -4x^3 * f '(x) + f(x) * -12x^2

    and

    b) h'(x) = 2/[tex]\sqrt{x}[/tex] * f '(x) + f(x) * -x^-2


    Sort of seems to simple... Thanks again
     
  2. jcsd
  3. Mar 3, 2008 #2
    a) Yes, b) [tex]\frac{2}{\sqrt{x}}[/tex] is not [tex]\frac{-1}{x^2}[/tex]
     
    Last edited: Mar 3, 2008
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