作者mqazz1 (无法显示)
看板Math
标题[线代] adj(A)
时间Fri Apr 1 19:09:06 2011
show thaat if matrix A is singular, then matrix adj A is singular
假设adj(A)为nonsingular
因A为singular => det(A)=0
因为 A*adj(A) = det(A)*I => A = det(A)(adj(A))^(-1) = O
所以
adj(A) = O
请问黄字是怎麽来的?
谢谢
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1F：推 attomahawk :因为 A 为 Singular => det(A) = 0 且 A^(-1)不存在 04/01 19:20
2F：推 attomahawk :A*adj(A) = det(A)*I = 数字0 * 单位矩阵 = 零矩阵 04/01 19:22