关于n维单形的一个向量恒等式

The vector identical equation on n-dimensional single-entity

首先给出n维单形面积外法向量的概念,然后建立任意n维单形n个侧面(n-1维单形)面积外法向量的一个恒等式,由此推出n维单形的射影定理和余弦定理。

This article first elucidates the concept of the acreage outer normal vector on \%n\%dimensional singleentity and then establishes an outer normal vector identical equation of any \%n\% sides(\%n\%1 dimensonal singleentity) of \%n\%dimensional singleentity,from which the projection theorem and the cosine theorem of \%n\%dimensional singleentity can be educed.