Đáp án:
$\begin{array}{l}
O = {\left( {\sqrt {14} - 3\sqrt 2 } \right)^2} + 6\sqrt {28} \\
= 14 - 2.\sqrt {14} .3\sqrt 2 + {\left( {3\sqrt 2 } \right)^2} + 6.\sqrt {4.7} \\
= 14 - 6.\sqrt 7 .\sqrt 2 .\sqrt 2 + 18 + 6.2\sqrt 7 \\
= 14 + 18 - 6.2\sqrt 7 + 6.2\sqrt 7 \\
= 32\\
Q = {\left( {2\sqrt 3 - 3\sqrt 2 } \right)^2} + 2\sqrt 6 + 3\sqrt {24} \\
= {\left( {2\sqrt 3 } \right)^2} - 2.2\sqrt 3 .3\sqrt 2 + {\left( {3\sqrt 2 } \right)^2} + 2\sqrt 6 + 3.\sqrt {4.6} \\
= 12 - 12\sqrt 6 + 18 + 2\sqrt 6 + 3.2\sqrt 6 \\
= 30 - 12\sqrt 6 + 2\sqrt 6 + 6\sqrt 6 \\
= 30 - 4\sqrt 6 \\
S = \sqrt {{{\left( {\sqrt 3 - 2} \right)}^2}} + \sqrt {{{\left( {\sqrt 3 - 1} \right)}^2}} \\
= \left| {\sqrt 3 - 2} \right| + \left| {\sqrt 3 - 1} \right|\\
= 2 - \sqrt 3 + \sqrt 3 - 1\\
= 1\\
U = \left( {\sqrt {19} - 3} \right)\left( {\sqrt {19} + 3} \right)\\
= {\left( {\sqrt {19} } \right)^2} - {3^2}\\
= 19 - 9\\
= 10\\
{\rm{W}} = \frac{{\sqrt 7 + \sqrt 5 }}{{\sqrt 7 - \sqrt 5 }} + \frac{{\sqrt 7 - \sqrt 5 }}{{\sqrt 7 + \sqrt 5 }}\\
= \frac{{{{\left( {\sqrt 7 + \sqrt 5 } \right)}^2} + {{\left( {\sqrt 7 - \sqrt 5 } \right)}^2}}}{{\left( {\sqrt 7 + \sqrt 5 } \right).\left( {\sqrt 7 - \sqrt 5 } \right)}}\\
= \frac{{7 + 2.\sqrt 7 .\sqrt 5 + 5 + 7 - 2\sqrt 7 .\sqrt 5 + 5}}{{7 - 5}}\\
= \frac{{7 + 7 + 5 + 5}}{2}\\
= \frac{{24}}{2} = 12
\end{array}$
