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There exists interval whose elements satisfy inequality.

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January 11, 2011
inequalities unsolvedinequalities

Problem Statement

Let 0x1x2xn10 \le x_1 \le x_2\le\cdots\le x_n \le 1. Prove that for all A1A \ge 1, there exists an interval II of length 2An2\sqrt[n]{A} such that for all xIx \in I, (xx1)(xx2)(xxn)A.|(x - x_1)(x - x_2) \cdots (x -x_n)| \le A.