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Homework Help: Polynomial Factors

  1. Jul 14, 2010 #1
    1. The problem statement, all variables and given/known data
    If we divide f(x)= x^3+qx^2-x-2 by x+1, we get the same remainder as if we divide it by x-2. Determine the value of q


    2. Relevant equations

    f(x)= x^3+qx^2-x-2

    3. The attempt at a solution

    I tried to plug in f(-1) into the equation, and then f(2) into the equation.. But i honestly do not understand how to go about finding the remainders.
     
  2. jcsd
  3. Jul 14, 2010 #2

    Hurkyl

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    Is it because you don't know how to divide polynomials? Or are you intimidated by having q as a coefficient?
     
  4. Jul 14, 2010 #3
    well yeah, i dont know what to do with q.
     
  5. Jul 15, 2010 #4

    eumyang

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    Don't be afraid of the q. If you evaluated f(-1), you should get an expression with q as the single variable. Likewise, you'll get another expression after evaluating f(2). Now, what do you know about f(-1) and f(2)?


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