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Polynomial Division

  1. Sep 28, 2008 #1
    Here is the problem I am working on:

    Find the quotient and remainder when P(x) = 7 x^6 - 9 x^5 + 8 x^4 + 9 x^3 + 4 x^2 - 6 x is divided by (x + 5).
    My answer that I came up with is this.
    Q = 7x^5 - 44x^4 + 228x^3 - 1131x^2 + 5659x
    R = -28301x

    I have done this using Long and Synthetic division and have come up with the same answer every time. Problem is, LonCapa says it is wrong. Anyone know why?

    7x^5–44x^4+228x^3–1131x^3 + 5659x​
    _____________________________________​
    X+5 | 7 x^6 - 9 x^5 + 8 x^4 + 9 x^3 + 4 x^2 - 6 x
    7 x^6 + 35x^5​
    -44x^5 + 8 x^4​
    -44 x^5 – 220 x^4​
    228 x^4 + 9 x^3​
    228 x^4 + 1140 x^3​
    - 1131 x^3 + 4 x^2​
    - 1131 x^3 -5655 x^2​
    5659 x^2 – 6x​
    5659x^2 + 28295x​
    -28301x​


    Thanks.

    :confused:
     
    Last edited: Sep 28, 2008
  2. jcsd
  3. Sep 29, 2008 #2

    tiny-tim

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    Hi mweaver68! :smile:

    erm … for x + 5, mustn't R be a constant, and Q usually end in a constant? :redface:
     
  4. Sep 29, 2008 #3
    Thanks. That's what I was forgetting. I needed to add a 0 to the end of the equation.

    :redface:
     
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