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# Algebra help again

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1. 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
2. (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.
3. The rational roots theorem is useful for determining the values of x to try to find factors.
4. (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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