Ответ:

  1. \(\sqrt{2}\cdot\sqrt{8}=\sqrt{16}=4\).
  2. \(\sqrt{1000}=\sqrt{100\cdot10}=10\sqrt{10}\).
  3. \(\sqrt{5}\cdot\sqrt{5}=5\).
  4. \(\sqrt{0{,}36}=0{,}6\), так как \(0{,}6^2=0{,}36\).
  5. \((4\sqrt{7})^2=4^2\cdot(\sqrt{7})^2=16\cdot7=112\).
  6. \(\sqrt{360}=\sqrt{36\cdot10}=6\sqrt{10}\).
  7. \(\sqrt{25-9}=\sqrt{16}=4\).
  8. \(\sqrt{25\cdot9}=\sqrt{225}=15\).