Roots of Polynomials: Finding g(y) with y1, y2, y3

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Homework Statement



Let x1, x2, x3 are the roots of the polynomial f(x)=x3+px+q, where f(x)\inQ[x], p\neq0. Find a polynomial g(y) of third degree with roots:

y1=x1/(x2+x3-q)
y2=x2/(x1+x3-q)
y3=x3/(x1+x2-q)

Homework Equations





The Attempt at a Solution



Any ideas? Thank you.
 
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Not guaranteeing a solution, but recall that a polynomial with roots can always be factored into the form y = (x - r1)(x - r2)(x - r3) where rn is a unique root. Try this with your three roots.
 
Thank you for the advice. I will use it.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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