矩阵方程X+A^TX^(-1)A=I二阶对称最大、最小解定理

A MAXIMAL ANCL MINIMAL SOLUTION THEOREM OF THE MATRIX EQUATION X + A^TX^(-1)A =I WHEN AIS 2×2 SYMETRIC

本文解决了矩阵方程Ｘ＋ＡＴＸ(－１)Ａ＝Ｉ二阶对称情形最大、最小解问题，并给出了解的形式。

In this paper,matrix equation X + ATX-1 A = I is proved to have maxium andminimum solution when A is a 2×2 symetric matrix.