JEE Mains · Maths · STD 12 - 3 and 4 . metrices and determinant
The number of distinct real roots of the equaiton, \(\left|\begin{array}{*{20}{c}}
{\cos \,\,x}&{\sin \,\,x}&{\sin \,\,x}\\
{\sin \,\,x}&{\cos \,\,x}&{\sin \,\,x}\\
{\sin \,\,x}&{\sin \,\,x}&{\cos \,\,x}
\end{array}\right|\,\, = \,\,0\) in the interval \(\left[ { - \frac{\pi }{4},\frac{\pi }{4}} \right]\) is
- A \(1\)
- B \(4\)
- C \(2\)
- D \(3\)
Answer & Solution
Correct Answer
(C) \(2\)
Step-by-step Solution
Detailed explanation
\(\begin{array}{*{20}{c}} {\cos x}&{\sin x}&{\sin x}\\ {\sin x}&{\cos x}&{\sin x}\\ {\sin x}&{\sin x}&{\cos x} \end{array} = 0\) \({R_1} \to {R_1} - {R_2}\) \({R_2} \to {R_2} - {R_3}\)…
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