Ответ:

  1. \(\sqrt{2}=2^{\frac{1}{2}}\).
  2. \(\dfrac{\sqrt{3}}{3}=\dfrac{3^{\frac{1}{2}}}{3^1}=3^{-\frac{1}{2}}\).
  3. \(\dfrac{1}{2\sqrt{2}}=\dfrac{1}{2\cdot2^{\frac{1}{2}}}=2^{-\frac{3}{2}}\).
  4. \(\sqrt[3]{25}=25^{\frac{1}{3}}\).
  5. \(\sqrt[4]{27}=27^{\frac{1}{4}}\).
  6. \(\sqrt[3]{\left(\dfrac{1}{5}\right)^2}=\left(\dfrac{1}{5}\right)^{\frac{2}{3}}=5^{-\frac{2}{3}}\).

Ответ: 1) \(2^{\frac12}\); 2) \(3^{-\frac12}\); 3) \(2^{-\frac32}\); 4) \(25^{\frac13}\); 5) \(27^{\frac14}\); 6) \(5^{-\frac23}\).