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Homework Help: How do i find the roots of this polynomial?

  1. Jun 24, 2013 #1

    i've tried the p/q calculations in accordance with the rational roots theorem but i've yet to find the answers...
  2. jcsd
  3. Jun 24, 2013 #2


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    You can either:
    1. Use trial and error to find a solution.
    2. Graph the equation in order to estimate a solution.
    3. Use the formula for the roots of a cubic equation (most complicated approach).

    See: http://en.wikipedia.org/wiki/Cubic_function
  4. Jun 24, 2013 #3

    D H

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    4. Use an approximation scheme such as regula falsi, secant method, or Newton's method.

    The rational root theorem says yields a small number of candidate rational roots. Not a single one of those candidates will yield a root. That doesn't mean there aren't any roots. It just means the root/roots aren't rational numbers.
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