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    Hello all,

    looking for a little help. Homework for next week includes the following question -

    What are the zeroes of f(x) = x3 + 5x2 - 7x + 1?

    where do I begin with this, do I start with polynomial long division?

    Thanks for looking in,

    Nonny
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    (Original post by vokeyuk)
    Hello all,

    looking for a little help. Homework for next week includes the following question -

    What are the zeroes of f(x) = x3 + 5x2 - 7x + 1?

    where do I begin with this, do I start with polynomial long division?

    Thanks for looking in,

    Nonny
    Try a few values of x around 0 which will make f(x)=0. Ideally you want to try the factors of the constant because the constant is the product of the roots. Once you have it, divide the polynomial through by (x-a) where x=a is your found solution. You'll end up with a quadratic which you can solve.
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    The rational roots theorem is useful for determining the values of x to try to find factors.
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    (Original post by RDKGames)
    Try a few values of x around 0 which will make f(x)=0. Ideally you want to try the factors of the constant because the constant is the product of the roots. Once you have it, divide the polynomial through by (x-a) where x=a is your found solution. You'll end up with a quadratic which you can solve.
    thank you, that makes more sense to me, appreciate your help.
 
 
 
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