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Math Help - polynomial equations - real roots

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    polynomial equations - real roots

    Determine the real roots of each equation

    (5x^2+20)(3x^2-48) = 0

    (x^2+1)(2x^2 - x - 13) = 0
    Last edited by advancedfunctions2010; March 11th 2010 at 12:00 PM.
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  2. #2
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    Quote Originally Posted by advancedfunctions2010 View Post
    Determine the real roots of each equation

    (5x^2+20)(3^2-48) = 0

    (x^2+1)(2x^2 - x - 13) = 0
    Possible typo in the first question? As it stands there are no real roots.

    If, as I suspect, you mean (5x^2+20)(3x^2-48)=0. In this case ignore the first bracket.

    Divide through by 3 and ignore the first brackets: x^2-16=0

    This is a classic example using the difference of two squares.

    ================================================== =

    With the second one you can also ignore the first bracket as it has no real solutions
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