# How can I find all the possible roots of a polynomial?

Is there any algorithm that can be used to find all the possible roots of a polynomial?

For example, I'd like to find all possible roots of the polynomial $x^3 + 3x^2 + 2x + 6$.

If I remember correctly, the possible rational roots of a polynomial are given by all factors of the constant term, divided by all factors of the leading coefficient - is this true, or is it false?

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@TheChaz Now is there an efficient algorithm for finding the irrational roots of a polynomial? –  Anderson Green Nov 4 '12 at 2:30
Yes --- Newton's Method, which see. –  Gerry Myerson Nov 4 '12 at 2:34
dichotomy, newton, etc... –  user31280 Nov 4 '12 at 2:35
@F'OlaYinka Can you explain what "dichotomy" refers to in this context? –  Anderson Green Nov 4 '12 at 2:36