D-resultant for Rational Functions
نویسندگان
چکیده
In this paper we introduce the D-resultant of two rational functions f(t), g(t) ∈ K(t) and show how it can be used to decide if K(f(t), g(t)) = K(t) or if K[t] ⊂ K[f(t), g(t)] and to find the singularities of the parametric algebraic curve define by X = f(t), Y = g(t). In the course of our work we extend a result about implicitization of polynomial parametric curves to the rational case, which has its own interest.
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