The values of $\theta $ satisfying $\sin 7\theta = \sin 4\theta - \sin \theta $ and $0 < \theta < \frac{\pi }{2}$ are

  • A

    $\frac{\pi }{9},\frac{\pi }{4}$

  • B

    $\frac{\pi }{3},\frac{\pi }{9}$

  • C

    $\frac{\pi }{6},\frac{\pi }{9}$

  • D

    $\frac{\pi }{3},\frac{\pi }{4}$

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