CBSE 2026 · Region 2 · Set 1 · Q6 · 1 mark
If $\displaystyle \left|\begin{array}{ccc}-1 & -2 & 5 \\ -2 & \mathrm{a} & -1 \\ 0 & 4 & 2 \mathrm{a}\end{array}\right|=-86$, then the sum of all possible values of a is
Official answer
From CBSE’s own marking scheme for this paper.
(C)
$\displaystyle -4$
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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.