$A$ and $B$ are two square matrices such that $A^2B = BA$. If $(AB)^{10} = A^K B^{10}$,then $k$ is:

Let $A = \begin{bmatrix} 1 & 2 & 2 \\ 2 & 1 & 2 \\ 2 & 2 & 1 \end{bmatrix}$,then:

If $x, y$ are any two non-zero real numbers, $a_{i j} = xi + yj$, $A = \{a_{i j}\}_{n \times n}$ and $P, Q$ are two $n \times n$ matrices such that $A = xP + yQ$, then

If $\left\{ \begin{bmatrix} 3 & 1 & 2 \\ 8 & 9 & 5 \\ 1 & 1 & 3 \end{bmatrix} \begin{bmatrix} 1 & 3 & 3 \\ 3 & 2 & 7 \\ 3 & 7 & 9 \end{bmatrix} \begin{bmatrix} 3 & 8 & 1 \\ 1 & 9 & 1 \\ 2 & 5 & 3 \end{bmatrix} \right\}^2 = \begin{bmatrix} a_1 & a_2 & a_3 \\ b_1 & b_2 & b_3 \\ c_1 & c_2 & c_3 \end{bmatrix}$,then the value of $|a_2 - b_1| + |a_3 - c_1| + |b_3 - c_2|$ is

Let $M = \begin{bmatrix} 0 & -\alpha \\ \alpha & 0 \end{bmatrix}$,where $\alpha$ is a non-zero real number and $N = \sum_{k=1}^{49} M^{2k}$. If $(I - M^2)N = -2I$,then the positive integral value of $\alpha$ is

If $\begin{bmatrix} a & b & c \\ d & e & f \\ g & h & i \end{bmatrix}$ is a skew-symmetric matrix and $b, c, f$ are non-zero real numbers, then $\frac{b}{c} = $