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Homework Help: Trouble solving derivative

  1. May 29, 2010 #1

    bk1

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    Hi everyone,

    I'm having trouble solving this one. I just don't really see what i'm doing wrong.

    1. The problem statement, all variables and given/known data
    X² - x - 2
    X² + 5x + 6


    2. Relevant equations



    3. The attempt at a solution
    (( x-1 ) * x² + 5x + 6 ) - (( x + 5 ) * x²-x-2 )
    ( x² + 5x + 6)²

    So 8x² -6x-16
    (x² + 5x + 6)²

    Now I know this isn't the correct awnser. Because it should say
    6x² + 16x + 4
    ( x² + 5x+6)²

    Could anyone point out to me what i'm doing wrong?
    Thanks in advance.
    Tim
     
  2. jcsd
  3. May 29, 2010 #2
    Re: Deriative...

    The derivative of x^2 is 2x, not x.
     
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