Question

Answer 1

2: Ta có: \(3\sqrt{\dfrac{2}{9}}-6\sqrt{\dfrac{3}{4}}+\sqrt{27}-\sqrt{2}\)

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

=0

3: Ta có: \(\left(\sqrt{28}+\sqrt{7}-2\sqrt{3}\right)\cdot\sqrt{7}+\sqrt{84}\)

\(=21-2\sqrt{21}+2\sqrt{21}\)

=21

Answer 2

4:Ta có: \(\left(\sqrt{6}+\sqrt{5}\right)^2-\sqrt{120}\)

\(=11+2\sqrt{30}-2\sqrt{30}\)

=11