CBSE 2025 · Region 5 · Set 1 · Q6 · 1 mark
If $\displaystyle \mathrm{A}=\left[\mathrm{a}_{\mathrm{ij}}\right]$ is a $\displaystyle 3 \times 3$ diagonal matrix such that $\displaystyle \mathrm{a}_{11}=1, \mathrm{a}_{22}=5$ and $\displaystyle \mathrm{a}_{33}=-2$, then $\displaystyle |\mathrm{A}|$ is :
Official answer
From CBSE’s own marking scheme for this paper.
(B)
$\displaystyle -10$
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CBSE Class 12 Mathematics past-paper question from the 2025board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.