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Решите задачу:

$\frac{1}{1- \sqrt{5}}- \frac{2}{5+ \sqrt{5}}= \frac{ 5+\sqrt{5}-2(1- \sqrt{5}) }{(1-\sqrt{5})(5+\sqrt{5})}=\frac{ 3+3\sqrt{5}}{(1-\sqrt{5})(5+\sqrt{5})}=\frac{ 3(1+\sqrt{5})}{(1-\sqrt{5})*\sqrt{5}*(\sqrt{5}+1)}=$ $\frac{ 3}{\sqrt{5}-5}=\frac{ 3(\sqrt{5}+5)}{(\sqrt{5}-5)(\sqrt{5}+5)}=\frac{ 3\sqrt{5}+15}{5-25}=-\frac{ 3\sqrt{5}+15}{20}$