A Short Proof of McDougall's Circle Theorem
نویسندگان
چکیده
This note offers a short, elementary proof of a result similar to Ptolemy’s theorem. Specifically, let di,j denote the distance between Pi and Pj . Let n be a positive integer and Pi, for 1 ≤ i ≤ 2n, be cyclically ordered points on a circle. If Ri := ∏ 1 ≤ j ≤ 2n j 6= i di,j , then n ∑
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عنوان ژورنال:
- The American Mathematical Monthly
دوره 121 شماره
صفحات -
تاریخ انتشار 2014