${{{{[4 + \sqrt {(15)} ]}^{3/2}} + {{[4 - \sqrt {(15)} ]}^{3/2}}} \over {{{[6 + \sqrt {(35)} ]}^{3/2}} - {{[6 - \sqrt {(35)} ]}^{3/2}}}} = $
$1$
$7/13$
$13/7$
None of these
The equation $\sqrt {(x + 1)} - \sqrt {(x - 1)} = \sqrt {(4x - 1)} $, $x \in R$ has
Solution of the equation ${4.9^{x - 1}} = 3\sqrt {({2^{2x + 1}})} $ has the solution
${4 \over {1 + \sqrt 2 - \sqrt 3 }} = $
$\sqrt {(3 + \sqrt 5 )} $ is equal to
If ${a^x} = bc,{b^y} = ca,\,{c^z} = ab,$ then $xyz$=