\[\sqrt{31} - \sqrt{3}\ \ и\ \ \ \sqrt{29} - \sqrt{5}\ \]
\[\left( \sqrt{31} - \sqrt{3} \right)^{2} = 31 - 2\sqrt{93} + 3 =\]
\[= 34 - 2\sqrt{93}\]
\[\left( \sqrt{29} - \sqrt{5} \right)^{2} =\]
\[= 29 - 2\sqrt{145} + 5 =\]
\[= 34 - 2\sqrt{145}\]
\[34 - 2\sqrt{93} > 34 - 2\sqrt{145}\]
\[\sqrt{31} - \sqrt{3} > \sqrt{29} - \sqrt{5}.\]