If the matrix $A=\left[\begin{array}{ccc}0 & -3 & x+y \\ 3 & x-2 y & 5 \\ -6 & -5 & 0\end{array}\right]$ is skew-symmetric then values of x and y respectively are: |
2, 2 3, 3 2, 4 4, 2 |
4, 2 |
The correct answer is Option (4) → 4, 2 $A^T=\left[\begin{array}{ccc}0 & -3 & -6 \\ -3 & x-2 y & -5 \\ x+y & 5 & 0\end{array}\right]$ so $A=-A^T$ $⇒\left[\begin{array}{ccc}0 & -3 & x+y \\ 3 & x-2 y & 5 \\ -6 & -5 & 0\end{array}\right]=\left[\begin{array}{ccc}0 & -3 & 6 \\ 3 & 2 y-x & 5 \\ -x-y & -5 & 0\end{array}\right]$ $x-2y=2y-x$ $⇒x=2y$ $x+y=6$ so $3y=6⇒y=2$ $x=4$ |