Practicing Success
If the matrix $A = \begin{bmatrix}0&x+y&1\\3&z&2\\x-y&-2&0\end{bmatrix}$ is skew-symmetric, then: |
$x = 2, y = 1, z=0$ $x =2, y = 2, z=0$ $x=-2, y=-1, z=0$ $x=-2, y =1, z=-1$ |
$x=-2, y=-1, z=0$ |
$A = \begin{bmatrix}0&x+y&1\\3&z&2\\x-y&-2&0\end{bmatrix}$ $A^T = \begin{bmatrix}0&3&x-y\\x+y&z&-2\\1&2&0\end{bmatrix}$ 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) $y = -1$ |