Cho hai đường tròn (O) và (O') cắt nhau tại hai điểm A và B. Trên đường thẳng AB lấy điểm M ( A nằm giữa M và B). Vẽ đường thẳng MO cắt đường tròn (O) tại C và D. Vẽ đường thẳng MO’ cắt đường tròn (O’) tại E và F. Chứng minh rằng: MC.MD = ME.MF

Bộ phận quan trọng nhất của cung phản xạ là bộ phận nào ?

Viết chương trình tính a mũ n biết a và n là các số nguyên được nhập từ bàn phím

Choose the best answer among A,B,C or D. (15 points) 1. My mother used to ………. research in this library when she was a student. A. make B. do C. making D. doing 2. Let’s go to the beach this weekend, ………… ? A shall we B. do we C. don’t we D. will we 3. I wish he ……….. that. A. doesn’t say B. didn’t say C. hasn’t said D. hadn’t said 4. My father has gone away. He’ll be back ……… a week. A. for B. at C. until D. in 5. Don’t do this all at once; Do it little .................... little. A. by B. to C. from D. with 6. They are both good ............. because they type carefully. A. typewriters B. typists C. typers D. typemen 7. We didn’t ...............to the station in time to catch the train. A. get B. reach C. arrive D. approach 8. I don’t think that purple shirt .............. with your yellow skirt. A. suits B. fits C. goes D. wears 9. We had to stop for gasoline at a filling ............... . A. garage B. service C. station D. pump 10. ................ you study harder, you won’t pass the examination. A. If B. Although C. Despite D. Unless 11. He ordered them …….. it again. A. don’t do B. not do C. not to do D. didn’t do 12. Quite soon, the world is going to ...................... energy resources. A. run out of B. get into C. keep up with D. come up again 13. We decided not to go camping because of the ………rain. A. great B. strong C. heavy D. extra 14. Mary works at a supermarket. She ………. $ 5 an hour. A. pays B. brings C. takes D. earns 15. The students have got ……….. news about their exams. A. many B. some C. few D. a few

tính diện tích xung quanh và diện tích toàn phần của hình lập phương có cạnh 4,5 cm

Exercise 1. Put the verbs in brackets into the correct form. 1. If the earth suddenly (stop) ………..spinning we all (fly)…………off it. 2. If you (smoke)……….. in a non-smoking compartment, the other passengers ………..(object) 3. (your parents/not/be) ………………………proud if they saw you now? 4. I’m broke, but I (have)…………….plenty of money now if 1 (not/spend) so much yesterday. 5. If we (work)…………all right,we(finish)………… in time; butwe have no intention of doing it 6. If we (have)………. a submarine now, we (use)………it toInvestigate the seabed.. 7.Were he ten years younger, he (take)….part in the Voyage around theworld. .8- Should you come late, they (not let)……………you in Exercise 2. Choose the best option to complete the sentences. 1. If I a lot of money now, I………a new car. a. have / will buy b. have / would buy c. had/ will buy d. had/ would buy. 2. If I you, I do that. a. am/ will b. were/ would c. were/ will d. had been/ would 3. If I were offered the job, I think I……… it. a. take b. will take c. would take d. would have taken 4. I would be very surprised if he………….. a. refuses b. refused c. had refused d. would refuse 5.. Many people would be out of work if that factory…………..down a. closes b. had closed c. closed d. would dose 6.If she sold her car, she…….. muchmoney. a. gets b. would get c. will get d. would have got 7. They would be disappointed if we …… . a. hadn’t come b. wouldn’t come c. don’t come d. didn’t come 8.Would John be angry if I ………his bicycle without asking? a. take b. took c. had taken d. would take 9.She terrible upset if I lost this ring. a. will be b. would be c. were d. had been 10. if someone in here with a gun, I would be very frightened. a. would walk b. walks c. had walked d. walked

Giải hệ phương trình sau bằng phương pháp thế: {5(x+2y)=3x-1 {2x+4=3(x-5y)-12

Cho tam giác ABC vuông ở A, phân giác BD. Kẻ DE vuông góc BC (E thuộc BC). Trên tia đối của tia AB lấy điểm F sao cho AF = CE. Chứng minh rằng: 1. Cho BC= 15cm, AB= 9cm. Tính độ dài cạnh AC. 2. BD là đường trung trực của AE 3. AD < DC. 4. Gọi M là trung điểm FC. Chứng minh: B, D, M thẳng hàng

Phân tích đa thức thành nhân tử x^2+x+1

Vẽ 5 con đậu mầm chồng lên nhau nha '-' Full line full màu