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Homework Help: Newton's Divided Difference Question

  1. Jul 13, 2008 #1
    This is a problem from the book section about Newton's Divided Differences, but I don't see how it really connects to the chapter other than that you draw out the triangle diagram.

    1. The problem statement, all variables and given/known data
    Define $P(x) = P(x+1)-P(x), where P is an unknown 4th degree polynomial
    and that
    $^2P(x) = $($P(x)) = $(P(x+1)-P(x)) = $P(x+1) - $P(x) = P(x+2) -2(P(x+1) +P(x))

    Given $^2 P(0) = 0, $^3 P(0) = 6, $^4 P(0) = 24

    Find $^2 P(10)

    2. Relevant equations

    3. The attempt at a solution
    I used a4x^4 + a3x^3 + a2x^2 + a1x +a0 = Pn(x) and plugging in the givens I got that:
    a4 = 1, a3 = -5, a2 = -8, but I wasn't able to get a1 and a0 because they cancel out each time. I am not sure if I need a1 and a0 to find $^2 P(10), or if there is another way to do it.

    Thanks in advance for any help.
  2. jcsd
  3. Jul 15, 2008 #2
    30 views and no replies? Am I posting this topic incorrectly?
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