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Simple derivative

  1. Mar 30, 2009 #1
    D= (x^2+x)^(1/2)

    I have a solutions manual here showing
    D' = (1/2)(x^2+x)^(-1/2) (2x+1)(x')
    but correct me if im wrong..
    D' = (1/2)(x^2+x)^(-1/2) (2x+1)(2x')
  2. jcsd
  3. Mar 30, 2009 #2


    User Avatar
    Homework Helper

    well you didn't state what you were taking derivatives with respect to.

    But if you have D(t)=f(x)

    then D'(t)=f'(x)* (dx/dt) = f'(x)*x'

    In your question; [itex]f(x)=\sqrt{x^2+x}[/itex]
  4. Mar 30, 2009 #3
    differentiating with respect to time t if you could please answer this simple question directly i would be glad especialy
  5. Mar 30, 2009 #4


    Staff: Mentor

    The first one is correct; the second one is incorrect.
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