2. Сравните \(7\sqrt{\frac17}\) и \(\frac12\sqrt{20}\).

\(7\sqrt{\frac17}=\frac7{\sqrt7}=\sqrt7\).

\(\frac12\sqrt{20}=\frac12\cdot2\sqrt5=\sqrt5\).

Так как \(\sqrt7>\sqrt5\), то \(7\sqrt{\frac17}>\frac12\sqrt{20}\).

Ответ: \(7\sqrt{\frac17}>\frac12\sqrt{20}\).