generates a list of the principal subresultant coefficients of the polynomials poly1 and poly2 with respect to the variable var.
computes the principal subresultant coefficients modulo the prime p.
Details and Options
- The first k subresultants of two polynomials a and b, both with leading coefficient one, are zero when a and b have k common roots.
- Subresultants returns a list whose length is Min[Exponent[poly1,var],Exponent[poly2,var]]+1. »
Basic Examples (2)
The first three principal subresultant coefficients (PSCs) are zero when there are three common roots, multiplicities counted:
PSCs of two cubic polynomials:
When the polynomials have a pair of equal roots, the first PSC disappears:
When two pairs of roots are equal, the first two PSCs disappear:
Properties & Relations (3)
Introduced in 1999
Updated in 2012