Question:medium
The function $f(x) = \sin x(1 + \cos x)$, $0 \le x \le \dfrac{\pi}{2}$, has a maximum value when $x$ equals
The function $f(x) = \sin x(1 + \cos x)$, $0 \le x \le \dfrac{\pi}{2}$, has a maximum value when $x$ equals
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Use $\cos 2x = 2\cos^2 x - 1$ to convert $f'(x)$ into a quadratic in $\cos x$, then solve by factoring.
Updated On: Apr 8, 2026
- $\dfrac{\pi}{6}$
- $\dfrac{\pi}{4}$
- $\dfrac{\pi}{3}$
- $\dfrac{\pi}{2}$
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The Correct Option is C
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