CBSE 2026 · Region 3 · Set 1 · Q6 · 1 mark
If $\displaystyle \mathrm{B}(\operatorname{adj} \mathrm{B})=\left[\begin{array}{ccc}\frac{1}{3} & 0 & 0 \\ 0 & \frac{1}{3} & 0 \\ 0 & 0 & \frac{1}{3}\end{array}\right]$, then the value of $\displaystyle \operatorname{det}\left(\mathrm{B}^{-1}\right)=$
Official answer
From CBSE’s own marking scheme for this paper.
(C)
$\displaystyle 3$
DeterminantsAdjoint and Inverse of a MatrixApplymcqmedium
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CBSE Class 12 Mathematics past-paper question from the 2026board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.