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Finding Polynomial Equation

  1. Oct 5, 2003 #1
    Sorry to keep asking questions...my teacher is horrible...

    Anyway, I need to find a polynomial equation with degree 8 and contains the roots (3 - 2i), (-5 + 7i), 0 (with multiplicity 3), -3, and 4 (with multiplicity 2).

    This is what I came up with:

    p(x) = (x - (3 - 2i))(x - (-5 + 7i))(x)^3(x + 3)(x - 4)^2

    Two things I'm wondering about (besides whether I got it right of course):

    1. Don't I need to add in the conjugates for 3 - 2i and -5 + 7i in the equation? In that case, the degree would have to be 10, no?

    2. Can I simplify this any further?

    Thanks again.
  2. jcsd
  3. Oct 5, 2003 #2


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    Staff Emeritus
    Science Advisor
    Gold Member

    You only need to include the complex conjugates if you are looking for a real polynomial; they're not necessary for complex polynomials.
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