Polynomial roots or discriminant

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    Polynomial Roots
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SUMMARY

The discussion centers on the impossibility of finding roots for certain polynomials, specifically referencing the Abel-Ruffini theorem, which states that the roots of the polynomial \(x^5 - x + 1\) cannot be expressed using rational numbers and radicals. Participants inquire about calculating the discriminant of the polynomial \(P(x) = x^n + ax^m + b\), which involves the determinant of the Sylvester matrix associated with \(P(x)\) and its derivative \(P'(x)\). The conversation highlights the limitations of traditional methods in polynomial root-finding.

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  • Understanding of polynomial functions and their properties
  • Familiarity with the Abel-Ruffini theorem
  • Knowledge of Sylvester matrices and their determinants
  • Basic calculus, specifically differentiation of polynomials
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  • Study the process of finding the discriminant of polynomials
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nergal
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Hi there,

I was wondering if it is possible to find the roots of the following polynomial
[tex] P(x)=x^n+a x^m+b[/tex]
or at least can I get the discriminant of it, which is the determinant of the Sylvester matrix associated to P(x) and P'(x).

Thanks
 
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nergal said:
Hi there,

I was wondering if it is possible to find the roots of the following polynomial
[tex] P(x)=x^n+a x^m+b[/tex]

The Abel-Ruffini theorem says that it's impossible to find the roots of ##x^5 - x +1## using only rational numbers and radicals and combinations of those. So that's a counterexample to being able to find all the roots.
 
Yes that's true, then do you have any idea how to get the discriminant ?
 

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