西安毛子科技大枣三XIDIAN UNIVERSITY+ 0002A(2)=0解：1）A(a)的非零1级子式为:0 (α+1)"+， ,(+1)°:: D(a)=1A(a)的非零二级子式为:02+0=2(a+1),-[0 (α+1)=2,-022+20(a+1)=(a+1)*.0( ) 2 2     + + , , 1 . ( ) 1  = D  1 A( )  的非零二级子式为: ( ) 2 0 2 1 , 0      + = + ( ) ( ) 2 3 2 0 1 . 0 1      + = + + 解：1） A( )  的非零1级子式为: ( ) 2 0 , 0 1    = + ( ) 2 2 0 0 ( ) 0 0 0 0 1 A        +   =     +  