固有函数系的完全性

The completenss of the system of eigenfunctions

在应用Ｓｔｕｒｍ－Ｌｉｏｕｖｉｌｅ理论的展开定理时，固有函数系是完全的，不能缺少某一固有函数．在应用分离变量法解某些定解问题时。

The system of eigenfuctions is complete and is short of some eigenfunction application the expansion theorem of the Sturm Liouville theory. This paper notes that it is easy to produce the causes of short of some eigenfunction, when solving some problems for determining solution to eguations of mathematical physics by method of separation variables.