Two Nonzero Component Lemma and Matrix Trigonometry

• 作者: Morteza Seddighin
• 来源期刊: 线性代数与矩阵理论研究进展(英文)
• 学科: 数学
• 关键词: MATRIX TRIGONOMETRY
• 年，卷（期）: 2017,（1）
• 页码范围: 1-6
• 页数: 6页
• 分类号: O1

摘要

In this paper we show that the author’s Two Nonzero Lemma (TNCL) can be applied to present a simple proof for a very useful equality which was first proved by Karl Gustafson in 1968. Gustafson used Hilbert space methods, including convexity of the Hilbert space norm, to prove this identity which was the basis of his matrix trigonometry. By applying TNCL, we will reduce the problem to a simple problem of ordinary calculus.