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Mathematics · 2026 · 1 mark
CBSE 2026 · Region 2 · Set 2 · Q15
If A = [1/2 cos x, - sin x; sin x, 1/2 cos x] and A + A^′= I, then value of x ∈[(-π)/2, (π)/2] is
If $\displaystyle \mathrm{A}=\left[\begin{array}{cc}\frac{1}{2} \cos x & -\sin x \\ \sin x & \frac{1}{2} \cos x\end{array}\right]$ and $\displaystyle \mathrm{A}+\mathrm{A}^{\prime}=\mathrm{I}$, then value of $\displaystyle x \in\left[\frac{-\pi}{2}, \frac{\pi}{2}\right]$ is
Official answer
(C)
$\displaystyle 0$
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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.