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Homework Help: Confirmation in my solution to finding these roots

  1. Oct 28, 2008 #1
    1. The problem statement, all variables and given/known data
    find the roots of:
    3x^2 − 4x + 2 = 0

    2. Relevant equations
    quadratic equation

    3. The attempt at a solution
    4+/- sqrt16-24/6


    4+/- isqrt4 sqrt2

    simplify a bit

    x= 2-2sqrt2i
    x= 2+2sqrt2i

    does this seem right?
  2. jcsd
  3. Oct 28, 2008 #2


    Staff: Mentor

    When you're typing mathematical expressions on a single line, you need to use parentheses to group things appropriately.

    For your equation, 3x^2 -4x + 2 = 0 (a quadratic equation), you can use the quadratic formula:
    x = (-b [tex]\pm[/tex] [tex]\sqrt{b^2 - 4*a*c}[/tex])/(2*a).

    Without the LaTeX coding, this can be written as

    x = (-b +/- sqrt(b^2 - 4ac))/(2a)

    What you have in your first line after applying the quadratic formula is this:
    4+/- sqrt16-24/6

    If you had used parentheses, you would have had a better chance of getting the right answer. How about giving them a try?
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