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Homework Help: Another Complex root problem

  1. Oct 24, 2007 #1
    1. The problem statement, all variables and given/known data
    State the number of complex roots and then identify what the roots are.

    18x^2 + 3x -1 = 0

    2. Relevant equations

    3. The attempt at a solution
    There are 2 complex roots.

    Okay. So I cant factor anything out of the equation and when you try to factor it by hand it doesnt work. So what should I do? quadratic formula? Please help me.
  2. jcsd
  3. Oct 24, 2007 #2


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    Staff Emeritus
    Science Advisor

    I would use the quadratic formula, yes.
  4. Oct 24, 2007 #3


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    Homework Helper

    Yes, quadratic formula.
  5. Oct 24, 2007 #4
  6. Oct 25, 2007 #5
    You can factor out the polynomial as
    18x^2 + 6x - 3x - 1
    = 6x(3x+1) - (3x+1)
    = (6x-1) (3x+1)
  7. Oct 25, 2007 #6


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    I wish you would stop titling these "complex roots". So far none of the problems you have posted has had complex roots!
  8. Oct 25, 2007 #7
    oh sorry. In my book that section says "complex roots" but next time I will try my best to label it appropriately.
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