Extended gcd

Returns the final results of the extended Euclidean algorithm: an extension to the Euclidean algorithm which computes, besides the greatest common divisor of polynomials $p$ and $q$, the coefficients of Bézout's identity, which are polynomials $r$ and $s$ such that $p*r+q*s=gcd(p,q)$

extended_gcd(Polynomials, Polynomials)

Description

Given two polynomials $p$ and $q$, returns a vector with three elements: the first one is the greatest common divisor of $p$ and $q$, the second and the third ones are $r$ and $s$, with the notation used above.