n c n :
(1)
, m n. , .
(1)
× = , (2)
- ( );
- - ;
- -.
(2) - , (2) .
(2), , (1).
(2) -1, :
-1× × = -1× Þ
× = -1× Þ
= -1×. (3)
, (3) - (2), , (3) (2), :
×( -1× ) = Þ
× -1× = Þ
× = Þ = .
, det A = D ¹ 0, .
. :
. 1) :
= ; = .
2) det A = D = 10.
3) -1.
:
11 = = - 11; 12 = - =13; 13 = = 2;
21 = - = 5; 22 = = - 5; 23 = - = 0;
31 = = 16; 32 = - = - 8; 33 = = - 2.
, :
= .
:
= .
-1:
-1= .
4) -:
= -1× = × = .
, :
x = 0.8; = - 0.4; z = 0.4.