Trigonometry in complex inner product spaces

被引:0
作者
Albahboh, Hussin [1 ]
Gingold, Harry [1 ]
Quaintance, Jocelyn [2 ]
机构
[1] West Virginia Univ, Dept Math, Morgantown, WV 26506 USA
[2] Univ Penn, Dept Comp Sci, Philadelphia, PA 10104 USA
关键词
Inner product space; Complex Hilbert space; Angle; Similarity; Trigonometry; Trigonometric formulas; Sine theorem; Cosine theorem; ANGLES;
D O I
10.1016/j.laa.2019.04.014
中图分类号
O29 [应用数学];
学科分类号
070104 ;
摘要
We adopt an appropriate definition of an angle in a Hilbert space over the complex field. It serves as a main tool for the enhancement of geometry and trigonometry of complex inner product spaces. A "sine theorem" is shown to hold based on which similarity theorems are proven. Trigonometric identities are shown to hold that lead to a main result that the sum of angles in a "triangle" in a complex Hilbert space is pi. Examples are given. (C) 2019 Elsevier Inc. All rights reserved.
引用
收藏
页码:216 / 234
页数:19
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