Mathematics · 2019
JEE Main · 9 April 2019, Shift 2 · Q64
The total number of matrices A = (0, 2 y, 1; 2 x, y, -1; 2 x, -y, 1),(x, y ∈ R, x ≠ y) for which A^T A =3 I_3 is:
The total number of matrices $\displaystyle \mathrm{A}=\left(\begin{array}{ccc}0 & 2 y & 1 \\ 2 x & y & -1 \\ 2 x & -y & 1\end{array}\right),(x, y \in \mathbf{R}, x \neq y)$ for which $\displaystyle \mathrm{A}^{\mathrm{T}} \mathrm{A}=3 \mathrm{I}_3$ is :
Official answer
(2)
$\displaystyle 4$
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JEE Main 2019 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.