Rút gọn:

a, A = \(\sqrt{\left(1-x\right)^2}-1\) với x < 1

b, B = \(\frac{3-\sqrt{x}}{x-9}\) với x ≥ 0 và x ≠ 9

c, C = \(\frac{x-5\sqrt{x}+6}{\sqrt{x}-3}\) với x ≥ 0 và x ≠ 9

d, D = 5 - 3x - \(\sqrt{25-10x+x^2}\) với x < 5

e, E = \(\sqrt{3a}.\sqrt{27a}\) với a ≥ 0

f, F = \(\frac{1}{a-1}\sqrt{9\left(a-1\right)^2}\) với a > 1

Give the correct word formation

1. We like their ........... (friendly)

2. The ......... between Vietnam and China is good (friend)

3. They seem to be .......... . We dislike them (friend)

4. There will be a .......... in this street (meet)

5. We saw .......... girls there (beauty)

6. Can you give me some .......... the next flights to Florida ? (inform)

Rewrite sentences using " I wish ......... "

1. I don't know many English words

2. My friend can not stay with me longer

3. I don't have time to go around the city

4. We don't have a computer therefore we can not get access to the internet

5. I can not go to the car show at the city show ground

Ex1: Find the mistake and correct it

1. Martha feeds the baby when I arrived at her house

2. He told: " I'm tired "

3. Simon plays the piano well, can't he ?

4. He would like going to Madrid when he finishes university

5. I'll leave the office when I will finish

6. She hasn't met him for last year

7. You mustn't make the beds. I've just made them

8. By the time the police arrived the burglars escaped

9. Both of them is from London

Ex2: Rewrite the sentences using the words given in bold type

1. It isn't necessary for you to take a jacket

Need ............

2. Shall I help you with your luggage ?

Would ..........

3. I advise you to see a dentist

Ought ...........

4. It's just possible that he'll phone tonight

May ..........

5. You are not allowed to talk during the exam

Mustn't ............

6. They don't have to go to the meeting this evening

Needn't .............

Cho (O; R) và một điểm A sao cho OA = 2R. Vẽ các tiếp tuyến AB, AC (B, C là các tiếp điểm). Đường thẳng OA cắt BC tại H, cắt cung nhỏ và cung lớn BC lần lượt tại M và N

a, CMR: OA vuông góc với BC và r2 = OA . HM

b, Vẽ cát tuyến bất kì ADE. Gọi K là trung điểm của DE. Chứng tỏ năm điểm A, B, O, K, C cùng thuộc một đường tròn.