Question:medium
The value of $a$ for which $f(x) = a\sin x + \dfrac{1}{3}\sin 3x$ has an extremum at $x = \dfrac{\pi}{3}$ is
The value of $a$ for which $f(x) = a\sin x + \dfrac{1}{3}\sin 3x$ has an extremum at $x = \dfrac{\pi}{3}$ is
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For extremum: set $f'(x) = 0$ at the given point and solve for the unknown parameter.
Updated On: Apr 8, 2026
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The Correct Option is C
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