Mathematics · 2025
JEE Main · 22 January 2025, Shift 2 · Q5
For a 3 × 3 matrix M, let trace (M) denote the sum of all the diagonal elements of M. Let A be a 3 × 3 matrix such that | A |=1/2 and trace ( A )=3.…
For a $\displaystyle 3 \times 3$ matrix M, let trace (M) denote the sum of all the diagonal elements of M. Let A be a $\displaystyle 3 \times 3$ matrix such that $\displaystyle |\mathrm{A}|=\frac{1}{2}$ and trace $\displaystyle (\mathrm{A})=3$. If $\displaystyle \mathrm{B}=\operatorname{adj}(\operatorname{adj}(2 \mathrm{~A}))$, then the value of $\displaystyle |\mathrm{B}|+$ trace (B) equals :
Official answer
From NTA’s final answer key for this paper.
(4)
$\displaystyle 280$
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JEE Main 2025 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.