# The number of distinct real roots of the equaiton, cos x sin x sin x sin x cos x sin x sinx sinx cosx = 0 in the interval , 4 4 é ù p p -ê ú ë û is :

Question:

The number of distinct real roots of the equaiton, $\left|\begin{array}{lll}\cos x & \sin x & \sin x \\ \sin x & \cos x & \sin x \\ \sin x & \sin x & \cos x\end{array}\right|=0$ in the interval $\left[-\frac{\pi}{4}, \frac{\pi}{4}\right]$ is :

1. 1

2. 4

3. 2

4. 3

Correct Option: 3

JEE Main Previous Year 1 Question of JEE Main from Mathematics Matrices and Determinants chapter.
JEE Main Previous Year Online April 9, 2016

Solution:

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