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Algebra/Chapter 10/Symmetric Polynomials/Elementary Symmetric Polynomials
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Let there be a polynomial of degree
By the Fundamental Theorem of Algebra, it has complex roots (with multiplicity). Then we can write:
As we know, Vieta's formulae link between the coefficients and roots of a polynomial:
As we can see, these sums are symmetric polynomial, and are called elementary symmetric polynomials.
Definition
The elementary symmetric polynomials in variables , are defined as such:
Elementary Symmetric Polynomials Permutations and Symmetry Fundamental Theorem of Symmetric Polynomials