Mathematics · 2020
JEE Main · 9 January 2020, Shift 1 · Q54
If the matrices A = [1, 1, 2; 1, 3, 4; 1, -1, 3], B = adj A and C=3 A, then (| adj B|)/(|C|) is equal to:
If the matrices $\displaystyle \mathrm{A}=\left[\begin{array}{ccc}1 & 1 & 2 \\ 1 & 3 & 4 \\ 1 & -1 & 3\end{array}\right], \mathrm{B}=\operatorname{adj} \mathrm{A}$
and $\displaystyle C=3 A$, then $\displaystyle \frac{|\operatorname{adj} B|}{|C|}$ is equal to :
Official answer
(2)
$\displaystyle 8$
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JEE Main 2020 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.