WBJEE · Maths · Trigonometric Equations
The number of real solutions of the equation \((\sin x-x)\left(\cos x-x^{2}\right)=0\) is
- A 1
- B 2
- C 3
- D 4
Answer & Solution
Correct Answer
(C) 3
Step-by-step Solution
Detailed explanation
Given, \((\sin x-x)\left(\cos x-x^{2}\right)=0\) \(\Rightarrow \quad \sin x=x\) or \(\cos x=x^{2}\) Now, if \(\sin x=x,\) then only one solution ie \(x=0\) is possible. Also, if \(\cos x=x^{2}\), then two solutions are possible. Hence, there are total 3 solutions.
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