1, You should not show off your expensive belongings. 

2, Did you have to get travel insurance when applying for a visa to Europe?

3, You mustn't smoke here.

4, We have to cut the grass in the garden twice a month.

Bài 1: Tìm x;

a)\(\sqrt{x+5}+\sqrt{9x+45}+\sqrt{9+45}=10\)

b)\(\sqrt{x^2-4x+4}=\sqrt{3+2\sqrt{2}}\)

\(\dfrac{\sqrt{2}}{1+\sqrt{2}-\sqrt{3}}\)

Trục căn thức ở mẫu:

Bài 2:Rút gọn:

a)\(\sqrt{200}-\sqrt{32}+\sqrt{72}\)

b)\(\sqrt{175}-\sqrt{112}+\sqrt{63}\)

c)\(4\sqrt{2}-3\sqrt{125}+5\sqrt{45}-15\sqrt{\dfrac{1}{5}}\)

Bài 1 : So sánh

a) \(\sqrt{144-36}\) và \(\sqrt{144}-\sqrt{36}\)

b)\(\sqrt{11-4\sqrt{7}}\) và \(\sqrt{7}-2\)

c)\(\sqrt{3+\sqrt{5}}\) + \(\sqrt{3-\sqrt{5}}\) và  \(2+\sqrt{3}\)

d)\(\sqrt{15}\) - \(\sqrt{6}\) và \(\sqrt{14}-\sqrt{5}\)