Se cunosc matricele![A=\left[\begin{array}{ccc}2&1&3\\5&4&6\end{array}\right]\\B=\left[\begin{array}{ccc}1&0\\0&1\end{array}\right]](https://tex.z-dn.net/?f=A%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D2%26amp%3B1%26amp%3B3%5C%5C5%26amp%3B4%26amp%3B6%5Cend%7Barray%7D%5Cright%5D%5C%5CB%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1%26amp%3B0%5C%5C0%26amp%3B1%5Cend%7Barray%7D%5Cright%5D "A=\left[\begin{array}{ccc}2&1&3\\5&4&6\end{array}\right]\\B=\left[\begin{array}{ccc}1&0\\0&1\end{array}\right]")
a) Să se calculeze produsul matriceal AxB;
b) Să se calculeze produsul matriceal BxA.
Răspunsuri la întrebare
Model de rezolvare doua matrice inmultite:
1 2 2 1 2 1
A= B=
2 3 3 2 3 1
l1xc1 l1xc2 l1xc3 l1xc4
A x B =
l2xc1 l2xc2 l2xc3 l2xc4
1x2+2x3 1x1+2x2 1x2+2x3 1x1+2x1
A x B =
2x2+3x3 2x1+3x2 2x2+3x3 2x1+3x1
8 5 8 3
A x B =
13 8 13 5
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Exercitiul nostru:
2 1 3 1 0
A = B=
5 4 6 0 1
AxB= nu se poate. Matricea B trebuie sa aiba 3 linii.
Calculam inmultirea lui BxA:
B= 1 0 A = 2 1 3
0 1 5 4 6
l1xc1 l1xc2 l1xc3
BxA =
l2xc1 l2xc2 l2xc3
1x2+0x5 1x1+0x4 1x3+0x6
BxA =
0x2+1x5 0x1+1x4 0x3+1x6
2 1 3
BxA =
5 4 6