CBSE 2024 · Region 4 · Set 2 · Q4 · 1 mark
If $\displaystyle \mathrm{A}=\left[\mathrm{a}_{\mathrm{ij}}\right]=\left[\begin{array}{ccc}2 & -1 & 5 \\ 1 & 3 & 2 \\ 5 & 0 & 4\end{array}\right]$ and $\displaystyle \mathrm{c}_{\mathrm{ij}}$ is the cofactor of element $\displaystyle \mathrm{a}_{\mathrm{ij}}$, then the value of $\displaystyle \mathrm{a}_{21} \cdot \mathrm{c}_{11}+\mathrm{a}_{22} \cdot \mathrm{c}_{12}+\mathrm{a}_{23} \cdot \mathrm{c}_{13}$ is :
Official answer
From CBSE’s own marking scheme for this paper.
(B)
$\displaystyle 0$
DeterminantsMinors and CofactorsApplymcqmedium
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CBSE Class 12 Mathematics past-paper question from the 2024board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.