Two vectors $\vec A$ and $\vec B$ have equal magnitudes. The magnitude of $(\vec A + \vec B)$ is $‘n’$ times the magnitude of $(\vec A - \vec B)$. The angle between $ \vec A$ and $\vec B$ is

  • [JEE MAIN 2019]
  • [JEE MAIN 2021]
  • A

    ${\cos ^{ - 1}}\left[ {\frac{{{n^2} - 1}}{{{n^2} + 1}}} \right]$

  • B

    ${\cos ^{ - 1}}\left[ {\frac{{n - 1}}{{n + 1}}} \right]$

  • C

    ${\sin ^{ - 1}}\left[ {\frac{{{n^2} - 1}}{{{n^2} + 1}}} \right]$

  • D

    ${\sin ^{ - 1}}\left[ {\frac{{n - 1}}{{n + 1}}} \right]$

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  • [JEE MAIN 2019]

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  • [AIPMT 1991]

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