`a)`\(\sqrt{7-4\sqrt{3}}+\sqrt{7+4\sqrt{3}}\)
\(=\sqrt{\left(\sqrt{3}-2\right)^2}+\sqrt{\left(\sqrt{3}+2\right)^2}\)
\(=\left|\sqrt{3}-2\right|+\left|\sqrt{3}+2\right|\)
\(=2-\sqrt{3}+\sqrt{3}+2\)
\(=4\)
`b)`\(2\sqrt{6-2\sqrt{5}}+3\sqrt{6+2\sqrt{5}}\)
\(=2\sqrt{\left(\sqrt{5}-1\right)^2}+3\sqrt{\left(\sqrt{5}+1\right)^2}\)
\(=2\left|\sqrt{5}-1\right|+3\left|\sqrt{5}+1\right|\)
\(=2\sqrt{5}-2+3\sqrt{5}+3\)
\(=5\sqrt{5}+1\)
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