a) [tex]\frac{\sqrt{6+2\sqrt{5}}}{1+\sqrt{5}}=\frac{|\sqrt{5}+1|}{1+\sqrt{5}}=\frac{1+\sqrt{5}}{1+\sqrt{5}}=1[/tex]
c) [tex]\frac{\sqrt{3-\sqrt{5}}}{\sqrt{2}}=\frac{\sqrt{6-2\sqrt{5}}}{2}=\frac{|\sqrt{5}-1|}{2}=\frac{\sqrt{5}-1}{2}[/tex]
b) [tex]\frac{\sqrt{9-6\sqrt{2}}-\sqrt{6}}{\sqrt{3}}=\frac{\sqrt{27-18\sqrt{2}}-\sqrt{18}}{3}=\frac{\sqrt{(\sqrt{18}-3)^2}-\sqrt{18}}{3}[/tex]
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