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Homework Help: How to solve what should be a simple variant of a quadratic

  1. Jul 2, 2010 #1
    Hi everyone,

    For some reason I can't put this together in my head. I have a series of equations that can be solved directly, but my resulting equation is of the form:

    Ax^2 + Bx + Cx^(-1) + D = 0

    Obviously the C/x term is the one throwing the wrench in the works here. Could anyone point me in the right direction?

    Thanks in advance!

    -Justin
     
  2. jcsd
  3. Jul 2, 2010 #2
    Nevermind... It's very easy. Turn it into a cubic equation by multiplying through by X, resulting in the readily solvable:

    Ax^3 + Bx^2 + Dx + C = 0
     
  4. Jul 2, 2010 #3

    HallsofIvy

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    Science Advisor

    And be sure to note that while x= 0 might satisfy the third degree equation, it cannot be a solution to the first equation.
     
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