CBSE 2024 · Region 3 · Set 1 · Q3 · 1 mark
Let $\displaystyle \mathrm{A}=\left[\begin{array}{ll}\mathrm{a} & \mathrm{b} \\ \mathrm{c} & \mathrm{d}\end{array}\right]$ be a square matrix such that adj $\displaystyle \mathrm{A}=\mathrm{A}$. Then, $\displaystyle (\mathrm{a}+\mathrm{b}+\mathrm{c}+\mathrm{d})$ is equal to :
Official answer
From CBSE’s own marking scheme for this paper.
(A)
$\displaystyle 2$ a
DeterminantsAdjoint and Inverse of a MatrixApplymcqmedium
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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.