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Mathematics · 2026 · 1 mark
CBSE 2026 · Region 2 · Set 1 · Q3
If A = [1, a, b; -1, 2, c; 0, 5, 3] is a symmetric matrix, then the value of 3 a + b + c is
If $\displaystyle \mathrm{A}=\left[\begin{array}{ccc}1 & \mathrm{a} & \mathrm{b} \\ -1 & 2 & \mathrm{c} \\ 0 & 5 & 3\end{array}\right]$ is a symmetric matrix, then the value of $\displaystyle 3 \mathrm{a}+\mathrm{b}+\mathrm{c}$ is
Official answer
(A)
$\displaystyle 2$
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CBSE Class 12 Mathematics past-paper question from the 2026 board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.