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Solving a Cubic Equation

  1. Aug 17, 2013 #1
    Can anyone help solve S3+101S2+(10K+100)S+100K to find the roots of S in terms of K
     
  2. jcsd
  3. Aug 17, 2013 #2
    If you want an exact solution (i.e. not a numerical approximation) then you will have to use Cardano's method. The cubic formula is a bit messy in its generality though.
    http://en.wikipedia.org/wiki/Cubic_function#Roots_of_a_cubic_function

    You could also try guessing some obvious solutions and factor them, which will simplify the cubic to a quadratic. But I didn't see any just by glancing at the equation.
     
  4. Aug 17, 2013 #3

    lurflurf

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