Q)
The function $ f(x)=-\Large\frac{x}{2}\normalsize+ \sin x $ is always increasing in \[(a)\;\bigg(-\frac{\pi}{2},\frac{\pi}{2}\bigg)\qquad(b)\;\bigg(0,\frac{\pi}{4}\bigg)\qquad(c)\;\bigg(\frac{\pi}{4},\frac{\pi}{2}\bigg)\qquad(d)\;\bigg(-\frac{\pi}{3},\frac{\pi}{3}\bigg)\qquad\]
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