Polynomial factor ($g\mid f$)

A polynomial factor $g$ of a polynomial $f$ satisfies $f=gh$ for another polynomial $h$. Common polynomial factors are cancelled when expressing a rational function in reduced form; its degree of a rational map of the Riemann sphere is determined after this cancellation.

A polynomial factor of each of two specified polynomials. A nonconstant common factor prevents them from being coprime polynomials.