phân tích:    x²-4x+9=x²-4x+4+5=(x-2)²+5>=5

=>1/(x-2)²+5 >=1/5

=>min A=1/5

<=>x=2

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SP : điểm do hs tick với nhau

4. Complete the second sentence so that it has similar meaning to the first:

1. Driving too fast is dangerous.

=> It’s......is dangerous to drive too fast..........................................................................................................................................

2. He isn’t strong. He can’t lift such a heavy box.

=> He is too......weak to lift a heavy box.................................................................................................................................

3. They plan to invite her for dinner tonight.

=> They are ...going to invite her for dinner tonight....................................................................................................................................

4. She can’t speak. She can’t hear.

=> She can neither ....speak not hear........................................................................................................................

5. The children liked to swim in the rain.

=> The children enjoyed....swimming in the rain................................................................................................................

6. How carefully he drives!

=> What ... a carefully driver !.........................................................................................................................................

7. We must cover electrical sockets because children fay to put anything into them.

=> Electrical sockets .....( không biết làm )....................................................................................................................

8. Nobody helps her with the housework.

=> She does .....does housework with herself................................................................................................................................

9. He missed the first bus. He got up late.

=> Because ......got up late so he missed the first bus.................................................................................................................................

10. He is very lazy, so he can’t get good marks.

=> He isn’t...hard - working so he can't get good marks................................................................................................. 

e mới học lớp 6 thôi , không làm nổi 

Còn bài 2 và 4 mình không làm được có làm cũng chỉ đc một ít 

3. Write a description of Hoa's living room. Use the sets of words and phrases provided:

1. This / Hoa’s / living room.

=> …This is Hoa's living room ……………………………………………………………………………………………………………………………………

2. There / rug / front of / fireplace.

=> …There is  a rug in front of the fireplace……………………………………………………………………………………………………………………………………

3. A dog / lying / rug.

=> …A dog is lying on the rug ……………………………………………………………………………………………………………………………………

4. On the fireplace / there / mirror.

=> ……On the fireplace , there is a mirrow …………………………………………………………………………………………………………………………………

5. There / some pictures / wall / near / mirror.

=> ……There are some pictures on the wall near the mirror…………………………………………………………………………………………………………………………………

6. The TV set / be / shelf / next / lamp.

=> …The TV set is on the shelf next to the lamp ……………………………………………………………………………………………………………………………………

7. There / be / another lamp / near / sofa.

=> …There is another lamp near the sofa ……………………………………………………………………………………………………………………………………

8. Near / lamp / be / the telephone.

=> ……Near the lamp , there is the telephone…………………………………………………………………………………………………………………………………

9. There / plant / behind / sofa / front / window.

=> …There are plants behind the sofa in front of the window ……………………………………………………………………………………………………………………………………

10. The stereo / be / between / sofa / television.

=> …The stereo is between the sofa and television……………………………………………………………………………………………………………