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Homework Help: Solve Polynomials

  1. Feb 22, 2009 #1
    1. The problem statement, all variables and given/known data

    [tex]f(x) = x^3 + x^2 - 11x^2 -9x +18[/tex]

    when

    [tex]f(x) = 6[/tex]


    2. Relevant equations

    Using Mathcad

    Polyroots, solve function,



    3. The attempt at a solution

    I dont know how to paste mathscad, but i can get solution using polyroots for

    [tex]f(x) = 0[/tex]

    I dont know how to modify the mathscad code so that i can get

    [tex]f(x) = 6[/tex]

    I know how to use the basic root, polyroot and solve functions.

    I have done an X/Y graph, but cant seem to get 6 on the y axis, always a little over or under.

    Help is really, really appreciated, needed a.s.a.p,

    Thanks
     
  2. jcsd
  3. Feb 22, 2009 #2

    cristo

    User Avatar
    Staff Emeritus
    Science Advisor

    Why not try and solve [tex]f(x)-6=0[/tex]?
     
  4. Feb 22, 2009 #3
    Yeah, your 100% right, thanks for that.

    Funny how the simple things always get over-looked.

    Thanks a million again
     
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