hãy vẽ đồ thị của các hàm số y=2x^2 ,y=-2x^2 .dựa vào đồ thị để trả lời các câu hỏi sau : a, nếu a>0 thì hàm số y=ax^2 đồng biến khi nào ? nghịch biến nào? Với giá trị nào của thì hàm số đạt gtnn ? có giá trị nào của x để hàm số đạt giá trị lớn nhất không ?

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A. LEXICO-GRAMMAR 1. Choose the best answer to complete the following sentences 1. A: “Those girls are very good at dancing!” - B: “ ___________” A. So do I! B. I know, they are C. Yes, they do! D. They were fine, thanks 2. I occasionally miss the bus so I have to take a taxi instead. A. never B. always C. sometimes D. rarely 3. There isn’t __________ for dinner, so I have to go to the market. A. any left B. some left C. any leaning D. some leaving 4. Public ___________ in this city is quite good, and it’s not expensive. A. journey B.travel C. vehicle D. transport 5. Bicycles ___________ in the driveway. A. must not leave B. must not be leaving C. must not be left D. must not have left 6. The film was so __________. However, my father saw it from beginning to end. A. interesting B. exciting C. boring D. fascinating 7. If the weather _____________ good, I _____________ camping with classmates. A. is / go B. is / will go C. will be / go D. will be / will go 8. Find the word which has a different sound in the part underlined. A. birthday B. mouthful C. breathe D. worth 9. Rob eats a lot of fast food and he __________ on a lot of weight. A. takes B. spends C. puts D. brings 10.You are not allowed to smoke in this hall. A. forbidden B. asked C. let D. made 11. “They listen to the music with great interest” means_____________ A. They enjoy the music. B. They hate the music. C. They dislike the music . D. They never listen to that music. 12. If people turn off all electric appliances in one hour all over the world, they can save lots of ______. A. electric B. electrical C. electrician D. electricity 13. These three Rs __________ reduce, reuse and recycle. A. stand up B. stand for C. ask for D. means 14. He _________ English in this school since he _____________ here. A. has taught/moved B. taught/moved C. taught/ has moved D. has taught/has moved 15. Find the word whose main stress pattern is different from others. A. beautiful B. interesting C. environment D. difference

2. Read the passage and choose the best answer to the following questions. Bangkok, the capital of Thailand, is a city of contrasts. It is an exciting, crowded, modern city and, at the same time, a city that is full of history. The streets of Bangkok are usually noisy and have too many people. Some people are selling food; others are selling clothing, cassette tapes, flowers, or souvenirs. Visitors love the river markets, the beautiful temples and architecture, and the nightlife. Most of the year, Bangkok is hotter than any other capital city in Asia, but from December to February, the weather is not as warm and so it is much more comfortable. Actually, it’s an interesting city to visit at any time of the year. The shopping is excellent, and the prices are not as high as in many other large cities in Southeast Asia. There is always so much to do in Bangkok at anytime of the day or night – from watching Thai dancing or boxing to taking a boat trip on the river or trying some of the delicious and spicy food. And if you get tired of the city and want a quiet place, there are beautiful beaches only two hours away by bus. 1. Which phrases can you use to describe the streets of Bangkok? A. a city of contrasts B. noisy and crowded C. full of history D. excited and modern 2. What does NOT interest visitors in Bangkok? A. the shopping B. sightseeing C. the weather D. the nightlife 3. “so much to do in Bangkok” means ____. A. easy to find a job in Bangkok B. much free time C. lot of entertainment D. lot of souvenirs 4. What visitors cannot see or watch at any time of the day? A. Thai dancing B. Thai boxing C. river markets D. nightlife 5. Where is the nearest beach from Bangkok? A. only two hours B. only two hours away C. only two hours from Bangkok D. only two hours away by bus