\[1)\ 3\sqrt{\frac{5}{9}} - \frac{1}{2}\sqrt{20} + 3\sqrt{180} - 4\sqrt{\frac{125}{4}} =\]
\[= 3 \bullet \frac{\sqrt{5}}{3} - \frac{1}{2}\sqrt{4 \bullet 5} + 3\sqrt{36 \bullet 5} - 4 \bullet \frac{\sqrt{25 \bullet 5}}{2} =\]
\[= \sqrt{5} - \frac{1}{2} \bullet 2\sqrt{5} + 3 \bullet 6\sqrt{5} - 2 \bullet 5\sqrt{5} =\]
\[= \sqrt{5} - \sqrt{5} + 18\sqrt{5} - 10\sqrt{5} =\]
\[= 8\sqrt{5}.\]
\[2)\ \frac{1}{\sqrt{6} - \sqrt{5}} - \frac{3}{\sqrt{5} + \sqrt{2}} - \frac{4}{\sqrt{6} - \sqrt{2}} =\]