Tateaki Sasaki
Abstract
Let P(z) be a univariate polynomial over C, having m close roots around the origin. We present a theorem which separates a cluster of m - k close roots of dk P/dzk around the origin from the other roots, where 0 ≤ k < m. We compare our theorem with those of Marden-Walsh and Yakoubsohn, and show superiority of our theorem.
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