The area of the triangle formed by the tangents from the points $(h, k)$ to the circle ${x^2} + {y^2} = {a^2}$ and the line joining their points of contact is

  • A

    $a{\rm{ }}\frac{{{{({h^2} + {k^2} - {a^2})}^{3/2}}}}{{{h^2} + {k^2}}}$

  • B

    $a{\rm{ }}\frac{{{{({h^2} + {k^2} - {a^2})}^{1/2}}}}{{{h^2} + {k^2}}}$

  • C

    $\frac{{{{({h^2} + {k^2} - {a^2})}^{3/2}}}}{{{h^2} + {k^2}}}$

  • D

    $\frac{{{{({h^2} + {k^2} - {a^2})}^{1/2}}}}{{{h^2} + {k^2}}}$

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