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Factoring Trinomials

  1. Sep 23, 2010 #1
    I need help trying to factor a trinomial. It has been a while, and I cant remember how to factor a trinomial with x^3. Please help.

    Sample problem...

    X^3 - 4X^2 + 5

    Thanks
     
  2. jcsd
  3. Sep 23, 2010 #2

    LCKurtz

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    Since factoring is the same problem as finding the roots, such a cubic can always be factored using tedious methods for solving for the roots.

    If you can find any root by inspection you can reduce it to a quadratic and you are home free. So I would look for rational roots which in this case will quickly find one. See

    http://en.wikipedia.org/wiki/Rational_root_theorem
     
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