Mathematics · 2021
JEE Main · 4 August 2021, Shift 1 · Q63
Let A = [x, 3, 2; 1, y, 4; 2, 2, z], x y z=60 and 8 x+4 y+3 z=20. If A ( adj A )=k I, then k is equal to
Let $\displaystyle \mathrm{A}=\left[\begin{array}{lll}x & 3 & 2 \\ 1 & y & 4 \\ 2 & 2 & z\end{array}\right], x y z=60$ and $\displaystyle 8 x+4 y+3 z=20$. If $\displaystyle \mathrm{A}(\operatorname{adj} \mathrm{A})=k \mathrm{I}$, then $\displaystyle k$ is equal to
Official answer
(3)
$\displaystyle 68$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.