CBSE 2024 · Region 1 · Set 2 · Q6 · 1 mark
If $\displaystyle \mathrm{a}_{\mathrm{ij}}$ and $\displaystyle \mathrm{A}_{\mathrm{ij}}$ represent the (ij)th element and its cofactor of $\displaystyle \left[\begin{array}{rrr}2 & -3 & 5 \\ 6 & 0 & 4 \\ 1 & 5 & -7\end{array}\right]$ respectively, then the value of $\displaystyle \mathrm{a}_{11} \mathrm{A}_{21}+\mathrm{a}_{12} \mathrm{A}_{22}+\mathrm{a}_{13} \mathrm{A}_{23}$ is :
Official answer
From CBSE’s own marking scheme for this paper.
(A)
$\displaystyle 0$
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.