Question

Answer 1

1) \(=2\sqrt{6}+3+2-2\sqrt{6}-\dfrac{\sqrt{5}\left(\sqrt{5}-1\right)}{\sqrt{5}-1}+\sqrt{5}\)

\(=5-\sqrt{5}+\sqrt{5}=5\)

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

 

Answer 2

4: Ta có: \(\dfrac{4}{3+\sqrt{5}}-\dfrac{15}{\sqrt{5}}+10\sqrt{\dfrac{1}{5}}+\sqrt{20}\)

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

=3