(Solved): 1. Compute the matrix-vector products \( A \mathbf{x} \), if possible \[ A=\left[\begin{array}{ccc ...

1. Compute the matrix-vector products \( A \mathbf{x} \), if possible \[ A=\left[\begin{array}{cccc} 1 & 5 & -2 & 0 \\ -3 & 1 & 9 & -5 \\ 4 & -8 & -1 & 7 \end{array}\right] \text { and } \mathbf{x}=\left[\begin{array}{c} 2 \\ -3 \\ 0 \\ -1 \end{array}\right] \] 2. If \( A \) is a \( 3 \times 5 \) matrix and \( b \) is a \( 5 \times 2 \) matrix, what are the sizes of \( A B \) and \( B A \),if they are defined.