The Univariate Discriminant via the Sylvester Resultant
نویسنده
چکیده
Remark 1.2 The Fundamental Theorem of Algebra enters in the very last inequality: the fact that having d distinct roots implies that Res(d,d−1)(f, f ) 6= 0. Later we will see a refinement of the above theorem giving a positive lower bound even when Res(d,d−1)(f, f )=0. ⋄ A key result we’ll need is the following algebraic identity. Lemma 1.3 Following the notation of Theorem 1.1, we have Res(d,d−1)(f, f )=(−1)c d ∏
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تاریخ انتشار 2015