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Mathematics · 2025 · 1 mark
CBSE 2025 · Region 2 · Set 1 · Q4
If A = [1, 12, 4 y; 6 x, 5, 2 x; 8 x, 4, 6] is a symmetric matrix, then (2 x+ y ) is
If $\displaystyle \mathrm{A}=\left[\begin{array}{ccc}1 & 12 & 4 \mathrm{y} \\ 6 x & 5 & 2 x \\ 8 x & 4 & 6\end{array}\right]$ is a symmetric matrix, then $\displaystyle (2 x+\mathrm{y})$ is
Official answer
(D)
$\displaystyle 8$
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CBSE Class 12 Mathematics past-paper question from the 2025 board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.