Ответ:

  1. \(\sqrt[3]{8x^6}=2x^2\).
  2. \(\sqrt{\frac{1}{4}x^2y^4}=\frac{|x|y^2}{2}\).
  3. \(\sqrt[3]{\frac{1}{27}a^3b^9}=\frac{ab^3}{3}\).
  4. \(\sqrt[4]{a^4b^8c^{12}}=|a|b^2|c|^3\).