1·In this paper we give a necessary and sufficient condition on diagonalization matrix.
本文给出矩阵可对角化的一个充要条件。
2·The author discusses a class of general of singular boundary value problems by using the first integral method, and the necessary and sufficient condition of positive solutions was obtained.
运用首次积分法讨论了较广泛的一类常微分方程边值问题,得到了正解存在的充要条件。
3·This paper studies the necessary and sufficient condition of uniformly convergent difference scheme for the elliptic-parabolic partial differential equation with a small parameter.
本文研究小参数椭圆-抛物偏微分方程一致收敛差分格式的充要条件。