A symmetric matrix is a square matrix that is unchanged when it is transposed I. e.A'=A.(对称矩 阵一矩阵的转置和它本身相等) 12)(12 23)(23 2021/1/21 10 cXt2021/1/21 10 cxt ❖ A symmetric matrix is a square matrix that is unchanged when it is transposed I.e. A’=A.（对称矩 阵—矩阵的转置和它本身相等）