Question

Rút gọn:

\(B=2\sqrt{18}-4\sqrt{32}+\sqrt{72}+3\sqrt{8}\)

\(C=\dfrac{\sqrt{8-2\sqrt{15}}-\sqrt{5}}{\dfrac{1}{\sqrt{3}-2}-\dfrac{1}{\sqrt{3}+2}}\)

Answer 1

B=\(2\sqrt{18}-4\sqrt{32}+\sqrt{72}+3\sqrt{8}\)

\(=6\sqrt{2}-16\sqrt{2}+6\sqrt{2}+6\sqrt{2}\)

\(=2\sqrt{2}\)

Answer 2

\(B=2\sqrt{18}-4\sqrt{32}+\sqrt{72}+3\sqrt{8}\)

\(=6\sqrt{2}-16\sqrt{2}+6\sqrt{2}+6\sqrt{2}\)

\(=\sqrt{2}\left(6-16+6+6\right)\)

\(=2\sqrt{2}\)