Mathematics · 2021
JEE Main · 18 March 2021, Shift 1 · Q79
The solutions of the equation |1+ sin^2 x, sin^2 x, sin^2 x; cos^2 x, 1+ cos^2 x, cos^2 x; 4 sin 2 x, 4 sin 2 x, 1+4 sin 2 x| =0,(0<x<π), are:
The solutions of the equation
$$\left|\begin{array}{rrr}
1+\sin ^2 x & \sin ^2 x & \sin ^2 x \\
\cos ^2 x & 1+\cos ^2 x & \cos ^2 x \\
4 \sin 2 x & 4 \sin 2 x & 1+4 \sin 2 x
\end{array}\right|=0,(0<x<\pi), \text { are : }
$$
Official answer
(3)
$\displaystyle \frac{7 \pi}{12}, \frac{11 \pi}{12}$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.