A = | 1 2 |
3 4
b = | 1 3 |
5 7
a* b = ?
Hello, ranjitbd!
If you know how to multiply matrices, exactly where is your difficulty?
If you don't know how, this is not the place to learn it.
Gtiven: .$\displaystyle A \:=\:\begin{vmatrix} 1&2 \\ 3&4 \end{vmatrix} \qquad B \:=\:\begin{vmatrix}1&3\\5&7 \end{vmatrix}$
Find: .$\displaystyle A\cdot B$
$\displaystyle A\cdot B \;=\;\begin{vmatrix}1&2\\3&4\end{vmatrix}\, \begin{vmatrix}1&3\\5&7\end{vmatrix}$ .$\displaystyle = \;\begin{vmatrix}(1)(1)+(2)(5) & (1)(3)+(2)(7) \\ (3)(1)+(4)(5) & (3)(3)+(4)(7)\end{vmatrix} \;=\;\begin{vmatrix}11 & 17 \\ 23 & 37 \end{vmatrix}$