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1: \(\left(\sqrt{5}+\sqrt{3}\right)\cdot\sqrt{8-2\sqrt{15}}\)

\(=\left(\sqrt{5}+\sqrt{3}\right)\cdot\sqrt{5-2\cdot\sqrt{5}\cdot\sqrt{3}+3}\)

\(=\left(\sqrt{5}+\sqrt[]{3}\right)\cdot\sqrt{\left(\sqrt{5}-\sqrt{3}\right)^2}\)

\(=\left(\sqrt{5}+\sqrt{3}\right)\left(\sqrt{5}-\sqrt{3}\right)\)

=5-3=2

2: \(\left(\sqrt{10}+\sqrt[]{6}\right)\cdot\sqrt{8-2\sqrt{15}}\)

\(=\left(\sqrt{5}+\sqrt{3}\right)\cdot\sqrt{2}\cdot\sqrt{\left(\sqrt{5}-\sqrt{3}\right)^2}\)

\(=\sqrt{2}\left(\sqrt{5}+\sqrt{3}\right)\left(\sqrt{5}-\sqrt{3}\right)\)

\(=\sqrt{2}\left(5-3\right)=2\sqrt{2}\)

3: \(\left(5+2\sqrt{3}\right)\cdot\sqrt{37-20\sqrt{3}}\)

\(=\left(5+2\sqrt{3}\right)\cdot\sqrt{25-2\cdot5\cdot2\sqrt{3}+12}\)

\(=\left(5+2\sqrt{3}\right)\sqrt{\left(5-2\sqrt{3}\right)^2}\)

\(=\left(5+2\sqrt{3}\right)\left(5-2\sqrt{3}\right)=25-12=13\)

4: \(\left(2+\sqrt{3}\right)\cdot\sqrt{7-4\sqrt{3}}\)

\(=\left(2+\sqrt{3}\right)\cdot\sqrt{\left(2-\sqrt{3}\right)^2}\)

\(=\left(2+\sqrt{3}\right)\left(2-\sqrt{3}\right)=4-3=1\)

5: \(\sqrt{2-\sqrt{3}}\left(\sqrt{6}+\sqrt{2}\right)\)

\(=\sqrt{4-2\sqrt{3}}\left(\sqrt{3}+1\right)\)

\(=\left(\sqrt{3}+1\right)\cdot\sqrt{\left(\sqrt{3}-1\right)^2}\)

\(=\left(\sqrt{3}+1\right)\left(\sqrt{3}-1\right)=3-1=2\)

6: \(\left(\sqrt{10}-\sqrt{14}\right)\cdot\sqrt{6+\sqrt{35}}\)

\(=\left(\sqrt{5}-\sqrt{7}\right)\cdot\sqrt{12+2\sqrt{35}}\)

\(=\left(\sqrt{5}-\sqrt{7}\right)\cdot\left(\sqrt{5}+\sqrt{7}\right)\)

=5-7=-2

7: \(\left(\sqrt{6}+\sqrt{10}\right)\cdot\sqrt{4-\sqrt{15}}\)

\(=\left(\sqrt{5}+\sqrt{3}\right)\sqrt{8-2\sqrt{15}}\)

\(=\left(\sqrt{5}+\sqrt{3}\right)\cdot\sqrt{\left(\sqrt{5}-\sqrt{3}\right)^2}\)

\(=\left(\sqrt{5}+\sqrt{3}\right)\left(\sqrt{5}-\sqrt{3}\right)=5-3=2\)

8: \(\sqrt{2+\sqrt{9+4\sqrt{2}}}\)

\(=\sqrt{2+\sqrt{8+2\cdot2\sqrt{2}\cdot1+1}}\)

\(=\sqrt{2+\sqrt{\left(2\sqrt{2}+1\right)^2}}=\sqrt{2+2\sqrt{2}+1}\)

\(=\sqrt{\left(\sqrt{2}+1\right)^2}=\sqrt{2}+1\)

9: \(\sqrt{5-\sqrt{13+\sqrt{48}}}\)

\(=\sqrt{5-\sqrt{12+2\cdot2\sqrt{3}\cdot1+1}}\)

\(=\sqrt{5-\sqrt{\left(2\sqrt{3}+1\right)^2}}=\sqrt{4-2\sqrt{3}}\)

\(=\sqrt{\left(\sqrt{3}-1\right)^2}=\sqrt{3}-1\)

10: \(\sqrt{8+2\sqrt{6-\sqrt{20}}}\)

\(=\sqrt{8+2\sqrt{5-2\sqrt{5}+1}}\)

\(=\sqrt{8+2\sqrt{\left(\sqrt{5}-1\right)^2}}\)

\(=\sqrt{8+2\left(\sqrt{5}-1\right)}=\sqrt{6+2\sqrt{5}}\)

\(=\sqrt{5+2\cdot\sqrt{5}\cdot1+1}=\sqrt{\left(\sqrt{5}+1\right)^2}=\sqrt{5}+1\)

11: \(\sqrt{\sqrt{5}-\sqrt{6-2\sqrt{5}}}\)

\(=\sqrt{\sqrt{5}-\sqrt{\left(\sqrt{5}-1\right)^2}}\)

\(=\sqrt{\sqrt{5}-\left(\sqrt{5}-1\right)}=\sqrt{\sqrt{5}-\sqrt{5}+1}\)

\(=\sqrt{1}=1\)

12: \(\sqrt{3-\sqrt{29-12\sqrt{5}}}\)

\(=\sqrt{3-\sqrt{20-2\cdot2\sqrt{5}\cdot3+9}}\)

\(=\sqrt{3-\sqrt{\left(2\sqrt{5}-3\right)^2}}\)

\(=\sqrt{3-\left(2\sqrt{5}-3\right)}=\sqrt{3-2\sqrt{5}+3}\)

\(=\sqrt{5-2\cdot\sqrt{5}\cdot1+1}=\sqrt{\left(\sqrt{5}-1\right)^2}=\sqrt{5}-1\)

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