Monomial basis

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In mathematics a monomial basis is a way to uniquely describe a polynomial using a linear combination of monomials. This description, the monomial form of a polynomial, is often used because of the simple structure of the monomial basis.

Polynomials in monomial form can be evaluated efficiently using the Horner algorithm.

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[edit] Definition

The monomial basis for the vector space Πn of polynomials with degree n is the polynomial sequence of monomials

1,x,x^2,.\ldots,x^n

The monomial form of a polynomial p \in \Pi_n is a linear combination of monomials

a_0 1 + a_1 x + a_2 x^2 + \ldots + a_n x^n

alternatively the shorter sigma notation can be used

p=\sum_{\nu=0}^n a_{\nu}x^\nu

[edit] Notes

A polynomial can always be converted into monomial form by calculating its Taylor expansion around 0.

[edit] Examples

A polynomial in Π4

1 + x + 3x4

[edit] See also