ik
, (5.1)
m n m × n. ik . m ¹ n, . m = n, . , m = 1, n > 1, ( 11 12 1 n) -. m > 1, n = 1, -.
. , , .
. A B ( = ), . , = , = 11 = b 11, a 12 = b 12, a 21 = b 21, a 22 = b 22, = .
.
5.1. m × n m × n, . : + = .
. + =
5.2. m × n, , .
5.3. m × n m × n , = + . : = . , .
. =
.
1. , . . + = + m × n.
2. , . . ( + ) + = + ( + ) , , .
3. + = + = A , .
5.4. A α α , α .
. 2 3 , A = , = .
2 3 = 2 3 = = .
5.5. m × n n × k, ij il i - blj j - , . .
cij = ai 1 b 1 j + ai 2 b 2 j + + ainbnj, i {1, 2, , m }; j {1, 2, , k }.
.
1) = ; 2) = ;
3) = .
5.6. n En.
1. , . . AB ¹ BA.
2. , . . A (BC) = (AB) C, .
|
|
3. A m × n, B n × k, A × En = A, En × B = B.
5.7.
=
,
t =
.
1. (At) t = A.
2. (A + B) t = At + Bt.
3. (AB) t = BtAt .
4. ( A) t = At .
. 2 At + (AB) t, = , = .
2 t + (AB) t = 2 + = 2 + = +
+ = .