Question

considere as matrizes
.... | -1 |
A=| 2 |
.... | 3 |

B=| 0 |
.... |-2 |
.... | 1 |
Determine o valor de 2B - A

Answer 1

$A = \left[\begin{array}{ccc}-1\\2\\3\end{array}\right] \\ B = \left[\begin{array}{ccc}0\\-2\\1\end{array}\right] \\ 2B-A = 2B + (-1)A\\ 2B-A = 2\left[\begin{array}{ccc}-1\\2\\3\end{array}\right] + (-1)\left[\begin{array}{ccc}0\\-2\\1\end{array}\right] \\ 2B-A = \left[\begin{array}{ccc}-2\\4\\6\end{array}\right] + \left[\begin{array}{ccc}0\\2\\-1\end{array}\right] \\ 2B-A = \left[\begin{array}{ccc}-2+0\\4+2\\6-1\end{array}\right] \\ 2B-A = \left[\begin{array}{ccc}-2\\6\\5\end{array}\right]$