Ответ:

  1. \(64^{1/2}=\sqrt{64}=8\).
  2. \(27^{1/3}=\sqrt[3]{27}=3\).
  3. \(8^{2/3}=(\sqrt[3]{8})^2=2^2=4\).
  4. \(81^{3/4}=(\sqrt[4]{81})^3=3^3=27\).
  5. \((8^{1/12})^{-4}=8^{-1/3}=\dfrac{1}{\sqrt[3]{8}}=\dfrac12\).