Mathematics · 2021
JEE Main · 25 July 2021, Shift 2 · Q61
The number of distinct real roots of |sin x, cos x, cos x; cos x, sin x, cos x; cos x, cos x, sin x| =0 in the interval -(π)/4 ≤ x ≤ (π)/4 is:
The number of distinct real roots of $\displaystyle \left|\begin{array}{ccc}\sin x & \cos x & \cos x \\ \cos x & \sin x & \cos x \\ \cos x & \cos x & \sin x\end{array}\right|=0$ in the interval $\displaystyle -\frac{\pi}{4} \leqslant x \leqslant \frac{\pi}{4}$ is:
Official answer
(1)
$\displaystyle 1$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.