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Math Help - X^3-5x^2+11=0, x=?

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    X^3-5x^2+11=0, x=?

    I cannot factor it and I want the x-values to be in fractions. Please help.
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    Quote Originally Posted by funzone36 View Post
    I cannot factor it and I want the x-values to be in fractions. Please help.
    There are none. Meaning you cannot write it in terms of fractions. Use the Rational Root theorem.
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  3. #3
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    The rational root theorem doesn't work. 1/1 and 11/1 all do work to make x = 0. So in the end, there's no accurate way to solve for x?
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    Quote Originally Posted by funzone36 View Post
    The rational root theorem doesn't work. 1/1 and 11/1 all do work to make x = 0. So in the end, there's no accurate way to solve for x?
    There's Cardano's method if you really really really need the exact answer. But I'd recommend that you eat a lot of carbohydrates before you attempt it because it's going to take a lot of effort.

    I'd stick with an approximation method.

    -Dan
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