1) Rút gọn a) \sqrt{6+2\sqrt{5}-\sqrt{13+\sqrt{48}}}
b) \sqrt{4-\sqrt{15}}\ast (4+\sqrt{15})\ast (\sqrt{10}-\sqrt{6})
c)D=1+\frac{\sqrt{3}}{2}/
1+\sqrt{1+\frac{\sqrt{3}}{2}}+1+\frac{\sqrt{3}}{2}/1-\sqrt{1+\frac{\sqrt{3}}{2}}
2) Giải phương trình
\sqrt{\sqrt{5}-\sqrt{3}\ast...