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Homework Help: Differentiation quotient rule question, am i wrong or is my book wrong?

  1. Aug 18, 2009 #1
    Differentiate with respect to x; (using the quotient rule)
    3/2x-1 (3 over 2x minus 1)
    dy/dx = (2x-1)(0) - (3)(2) / (2x-1)^2
    dy/dx = -6/(2x-1)^2

    but my book gives -2/(2x-1)^2

    y = u/v and i take
    u = 3 and
    v = 2x-1.

    dy/dx = v(du/dx) - u(dv/dx) / (v)^2

    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Aug 18, 2009 #2
    Assuming the question is to find

    [tex]\frac{d}{dx} \; \frac{3}{2x-1} [/tex]

    then your answer is correct. Whoever wrote the solutions probably forgot all about the 3.

    Last edited: Aug 18, 2009
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