57. Вычислите: 1) \(64^{\frac{2}{3}}\); 2) \(27^{\frac{1}{3}}\); 3) \(8^{\frac{2}{3}}\); 4) \(81^{\frac{3}{4}}\); 5) \(16^{-0,75}\); 6) \(9^{-1,5}\).

1. \(64^{\frac{2}{3}}=(\sqrt[3]{64})^2=4^2=16\).
2. \(27^{\frac{1}{3}}=\sqrt[3]{27}=3\).
3. \(8^{\frac{2}{3}}=(\sqrt[3]{8})^2=2^2=4\).
4. \(81^{\frac{3}{4}}=(\sqrt[4]{81})^3=3^3=27\).
5. \(16^{-0,75}=16^{-\frac{3}{4}}=\frac{1}{(\sqrt[4]{16})^3}=\frac{1}{8}\).
6. \(9^{-1,5}=9^{-\frac{3}{2}}=\frac{1}{(\sqrt{9})^3}=\frac{1}{27}\).

Ответ: 1) 16; 2) 3; 3) 4; 4) 27; 5) \(\frac18\); 6) \(\frac1{27}\).