If the matrix $A = \begin{bmatrix}0&x+y&1\\3&z&2\\x-y&-2&0\end{bmatrix}$ is skew-symmetric, then:
Answer & explanation
Correct answer: option 3
$A = \begin{bmatrix}0&x+y&1\\3&z&2\\x-y&-2&0\end{bmatrix}$
$A^T = \begin{bmatrix}0&3&x-y\\x+y&z&-2\\1&2&0\end{bmatrix}$
so skew symmetric
$⇒A=-A^T⇒\begin{bmatrix}0&x+y&1\\3&z&2\\x-y&-2&0\end{bmatrix}=\begin{bmatrix}0&-3&y-x\\-x-y&-z&2\\-1&-2&0\end{bmatrix}$
So,
$x+y=-3$ ...(i)
$x-y=-1$ ...(ii)
$z = -z$
$z=0$
Adding eq. (i) and (ii)
$2x = -4⇒x=-2$
form (i) $y = -1$