If $\cos 2\theta = (\sqrt 2 + 1)\,\,\left( {\cos \theta - \frac{1}{{\sqrt 2 }}} \right)$, then the value of $\theta $ is

  • A

    $2n\pi + \frac{\pi }{4}$

  • B

    $2n\pi \pm \frac{\pi }{4}$

  • C

    $2n\pi - \frac{\pi }{4}$

  • D

    None of these

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