For any $\theta \, \in \,\left( {\frac{\pi }{4},\frac{\pi }{2}} \right)$, the expression $3\,{\left( {\sin \,\theta  - \cos \,\theta } \right)^4} + 6{\left( {\sin \,\theta  + \cos \,\theta } \right)^2} + 4\,{\sin ^6}\,\theta $ equals

  • [JEE MAIN 2019]
  • A

    $13 - 4\,{\cos ^2}\,\theta \, + 6\,{\sin ^2}\,\theta \,{\cos ^2}\,\theta $

  • B

    $13 - 4\,{\cos ^6}\,\theta \,$

  • C

    $13 - 4\,{\cos ^2}\,\theta \, + 6\,\,{\cos ^4}\,\theta $

  • D

    $13 - 4\,{\cos ^4}\,\theta \, + 2\,{\sin ^2}\,\theta \,{\cos ^2}\,\theta $

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