Ответ:

  1. \(\sqrt{36b}-\sqrt{16b}+2\sqrt b=6\sqrt b-4\sqrt b+2\sqrt b=4\sqrt b\).
  2. \(4\sqrt2+\sqrt{50}-\sqrt{18}=4\sqrt2+5\sqrt2-3\sqrt2=6\sqrt2\).
  3. \(\sqrt3(2\sqrt3+\sqrt{12})=\sqrt3(2\sqrt3+2\sqrt3)=12\).
  4. \((\sqrt5-2)^2=5-4\sqrt5+4=9-4\sqrt5\).
  5. \((\sqrt3-\sqrt2)(\sqrt3+\sqrt2)=3-2=1\), по формуле разности квадратов.
  6. \(\frac15\sqrt{300}-4\sqrt{\frac3{16}}-\sqrt{45}=2\sqrt3-\sqrt3-3\sqrt5=\sqrt3-3\sqrt5\).
  7. \((3\sqrt2-1)(\sqrt8+2)=(3\sqrt2-1)(2\sqrt2+2)=12+6\sqrt2-2\sqrt2-2=10+4\sqrt2\).
  8. \((\sqrt5+2)^2-(3-\sqrt5)^2=(9+4\sqrt5)-(14-6\sqrt5)=10\sqrt5-5\).