${{\sqrt {6 + 2\sqrt 3 + 2\sqrt 2 + 2\sqrt 6 } - 1} \over {\sqrt {5 + 2\sqrt 6 } }}$
$1$
$-1$
$0$
None of these
${4 \over {1 + \sqrt 2 - \sqrt 3 }} = $
If $a = \sqrt {(21)} - \sqrt {(20)} $ and $b = \sqrt {(18)} - \sqrt {(17),} $ then
The value of the fifth root of $10^{10^{10}}$ is
The rationalising factor of $2\sqrt 3 - \sqrt 7 $ is
The value of $\sqrt {[12\sqrt 5 + 2\sqrt {(55)} ]} $ is