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If [2  x  3][−10−1−110011][x0−1]=[−4][2\ \ x\ \ 3]\begin{bmatrix}-1 & 0 & -1\\ -1 & 1 & 0\\ 0 & 1 & 1\end{bmatrix}\begin{bmatrix}x\\0\\-1\end{bmatrix}=[-4], then the value(/s) of xx is

Solution

✅ Correct Option: 3

Multiplying the row by the matrix gives [−2−x   x+3   1][-2-x\ \ \ x+3\ \ \ 1]. Taking the product with the column gives (−2−x)x−1=−4(-2-x)x-1=-4, i.e. x2+2x−3=0x^2+2x-3=0, so x=−3x=-3 or x=1x=1.

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