1. tính giá trị biểu thức :

a) \(\sqrt{\dfrac{2}{3}}+2\sqrt{\dfrac{3}{2}}-\sqrt{6}\)

b) \(3\sqrt{\dfrac{2}{5}}+\sqrt{\dfrac{5}{2}}-2\sqrt{10}\)

c) \(-\sqrt{\dfrac{3}{5}}+3\sqrt{\dfrac{5}{3}}-4\sqrt{15}\)

d) \(\dfrac{2}{\sqrt{6}-2}+\dfrac{2}{\sqrt{6}+2}+\dfrac{5}{\sqrt{6}}\)

I. viết lạ câu :

1. Lan said " I have to go to the school library now " . Lan ................................................................

2. Getting to school by bus is not convenient . It ..............................................................

3. Nobody told me Mary was ill. I.................................................................

4. I was listening to music when you called me yesterday . What .....................................................

5 . "Do you enjoy your English class,Nam ? '' . The teacher said ..............................................

6 . You will be given new information before you live . We ..................................................

7 . "The shop is closing in half an hour ''. The shopkeeper said ........................................................

8. Traveling around the world is interresting . It is ...........................................................

9 . The sun is much hotter than the moon . The moon is not ....................................................

10 . I want you to help me with the housework . Can .........................................................

11 . Could I smoke in here ? Do .....................................................

12. She was so tired that she could not walk any further . She was too ...............................................................

II. hoàn thanh câu dùng từ gợi ý

a) He/ hurry / bus stop / order / not / late / school .

b) I/ pick/ you / 8 pm / tonight ?

c) I / want / you/ help / fix / computter.

d) It / not difficult / keep / people / litter .

giải các phương trình :

a) \(\left(\sqrt{x}-7\right)\left(\sqrt{x-8}\right)=x+11\)

b) \(\left(\sqrt{x}+3\right)\left(\sqrt{x}-5\right)=x-17\)

c) \(1-\dfrac{2\sqrt{x}-5}{6}=\dfrac{3-\sqrt{x}}{4}\)

d) \(\left(\sqrt{x}+3\right)^2-x+3=0\)