CBSE 2026 · Region 1 · Set 1 · Q5 · 1 mark
One of the values of $\displaystyle x$ for which $\displaystyle \left|\begin{array}{cc}\cos x & \sin x \\ -\cos x & \sin x\end{array}\right|=1$ is
Official answer
From CBSE’s own marking scheme for this paper.
(B)
$\displaystyle \frac{\pi}{4}$
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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.