If $\cos 3\theta = \alpha \cos \theta + \beta {\cos ^3}\theta ,$ then $(\alpha ,\beta ) = $

  • A

    $(3,\,4)$

  • B

    $(4,\,3)$

  • C

    $( - 3,\,4)$

  • D

    $(3,\, - 4)$

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