Mathematics · 2021
JEE Main · 17 March 2021, Shift 1 · Q63
If A = (0, sin α; sin α, 0) and det ( A^2-1/2 I )=0, then a possible value of α is:
If $\displaystyle \mathrm{A}=\left(\begin{array}{lr}0 & \sin \alpha \\ \sin \alpha & 0\end{array}\right)$ and $\displaystyle \operatorname{det}\left(\mathrm{A}^2-\frac{1}{2} \mathrm{I}\right)=0$, then a possible value of $\displaystyle \alpha$ is :
Official answer
(1)
$\displaystyle \frac{\pi}{4}$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.