\(\left(\frac{2}{\sqrt{3}+1}+\frac{3}{\sqrt{3}-2}+\frac{15}{3-\sqrt{3}}\right).\frac{1}{\sqrt{3}+5}\)
= \(\left[\frac{2\left(\sqrt{3}+1\right)}{2}+\frac{2\left(\sqrt{3}+2\right)}{1}+\frac{15\left(3+\sqrt{3}\right)}{6}\right].\frac{1}{\sqrt{3}+5}\)
= \(\left[\frac{2\left(\sqrt{3}+1\right)-6\left(\sqrt{3}+2\right)+15\left(\sqrt{3}+3\right)}{2}\right].\frac{1}{\sqrt{3}+5}\)
= \(\left[\frac{2\sqrt{3}+2-6\sqrt{3}-12+5\sqrt{3}+15}{2}\right]\).\(\frac{1}{\sqrt{3}+5}\)
= \(\frac{\sqrt{3}+5}{2}.\frac{1}{\sqrt{3}+5}\)
= \(\frac{1}{2}\)