MCQ
The number of points in $(-\infty, \infty)$, for which $x^2-x \sin x-\cos x=0$, is
- A$6$
- B$4$
- ✓$2$
- D$0$
✓
Answer
Correct option: C.
$2$
c
$x^2=x \sin x+\cos x $
$x^2=x \sin x+\cos x $
$f(x)=x^2 $
$g(x)=x \sin x+\cos x $
$g^{\prime}(x)=\sin x+x \cos x-\sin x $
$g^{\prime}(x)=x \cos x$
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