1.Cho A= x/x−4 + 1/ √x - 2 + 1/ √x + 2. Với x ≥ 0, x ≠ 4 a. Rút gọn A b. Tìm x để A > 1 2.Cho (P) y= 2x^2 và d : y= mx + n a. Tìm mn biết d qua A( 1,2 ) và d song song y = 4x + 1 b. Vẽ (P) c. Tìm giao điểm (P) và d 3. Cho tam giác ABC có 3 góc nhọn. 2 đường cao tam giác ABC là AD và BE cắt tại H. a. C/M CDHE nội tiếp đường tròn b. C/M HA. HD = HB.HE c. Gọi I là tâm đường tròn ngoại tiếp CDHE. Chứng minh IE là tiếp tuyến của đường tròn đường kính AB

gen cây cao kết hợp với gen cây thấp tìm p và vẽ sơ đồ lai (biết gen cây cao trội hoàn toàn gen cây thấp

Vật chất và ý thức cái nào có trước cái nào có sao cái nào quyết định cho ví dụ

Giúp mình lun nè cb ik học òi :<

V. Choose the correct answer to complete each of the following sentences. THERE CAN BE MORE THAN ONE CORRECT ANSWER TO SOME QUESTIONS. Write your answers in the space provided. (70 points) 1. When I finish my writing this composition, I’m going to ___________ and go to bed. A. make time B. hit the hay C. hit the big time D. call it a day 2. Marry usually buys her clothes ___________. It’s cheaper than going to a dressmaker. A. in public B. on the shelf C. off the peg D. on the house 3. You are at ___________ to do what you like. A. freedom B. odds C. disposal D. liberty 4. David has not seen Linda for fifteen years and has ___________ of her address. A. no idea B. nothing C. no thought D. no mind 5. I have three brothers, ___________ of whom were there. A. none B. neither C. no one D. either 6. - “Why don’t we listen to some news programmes.” - “___________” A. I don’t care for them either. B. Because they’re usually so boring C. Because I like pop music and I like presenter D. Yes, whenever I’m in my father’s car! 7. If you want to ___________ success in life, you have to work hard. A. achieve B. receive C. award D. earn 8. ___________ he was lazy, he failed the exam. A. Now that B. so C. consequently D. Thus 9. - A: “Will the Browns be invited?” - B: “ I___________” A. expect so not B. so expect C. expect so D. don’t expect 10. Anyone ordering a new MP3 player ___________ the end of the month will receive a free extra set of headphone. A. at B. in C. upon D. before 11. My job is so ___________ that I don’t think I’ll be able to take a summer break. A. persisting B. hard C. demanding D. tough 12. We ___________ the beginning of the film if we had gone to the cinema 15 mimutes earlier. A. would have never missed B. would never miss C. would never have missed D. never missed 13. He regrets___________ that car. A. not buying B. not to buy C.having not bought D. not having bought 14. Paula would like to___________by the time he is 45. A. travel B. to travel C. be going to travel D. have traveled 15. It is ___________ knowledge that newspapers report news. A. plain B. common C. easy D. simple 16. ___________ ,the balcony chairs will be ruined in this weather. A. Leaving uncovered B. Having lelf uncovered C. lelf uncovered D. Been lelf uncovered 17. ___________ fire, please break the glass and ring the bell. A. In case of B. During C. Because of D. With a view to 18. The strike was ___________ owing to a last-minute agreement with the management. A. called off B. broken up C. set back D. put down 19. I’m amazed that this game ever___________ - it’s so silly! A. took in B. caught on C. took up D. caught by 20. The match will be screened on ITV with ___________ commentary by Sandy Curley. A. lively B. live C. alive D. living 21. It was ___________that even Smith’s fans couldn’t believe it. A. such a surprising victory B. so surprising a victory C. too surprising D. surprising 22. The first time I noticed something wrong was___________ I got home. A. when B. whether C. since D. until 23. ___________, he cannot make ends meet. A. Hard though he works B. Although he works hard C. He works hardly D. Hard as he work 24. Everyone hoped that he would ________ after the operation. A. pull through B. pull over C. get better D. pull out 25. ___________ new hostel for ___________ poor is being built in___________town centre. A. The/the/a B. A/Ø/ theC. The/ a /a D. A/ the/ the 26. I saw him hiding something in a ___________ bag. A. small plastic black B. black small plastic C. small black plastic D. plastic small black 27. The table___________when it was being moved to another room. A. was broken B. broke C. got breaking D. got broken 28. “Did you meet Ann here at the university? “No, We ___________ when I started college. A. have already met B. had already met C. had already been meeting D. have already been meeting 29. Of all the three sisters, Lan is ___________. A. the best and most qualified B. the most qualified and best C. the most qualified and the best D. the best and the most qualified 30. He offered to ___________ her a favour as the suitcase was too heavy for her to carry. A. show B. lend C. help D. do 31. Smoke from factories can cause air___________. A. pollute B. pollution C. polluting D. pollutant 32. Writers and novelists are___________people. A. imaginary B. imaginative C. imaginable D. imagined 33. At the party last night, I met a lot of ___________ people. A. interested B. interest C.interesting D. interestingly 34. I was the first person ___________ the accident. A. to witness B. had witnessed C. to have witnessed D. to be witnessed 35. By the time Peter came back, ___________ for Singapore. A. I left B. I have left C. I had left D. he will have left

Một ôtô đang chạy với vận tốc là 10m/s thì hãm phanh chuyển động chậm dần đều và khi đi thêm 84m thì vận tốc còn 4m/s a) Tính gia tốc của xe và thời gian xe đi trên đoạn đường 84m b) Tính thời gian từ lúc hãm phanh đến lúc xe đi được 75m c) Tính thời gian và quãng đường mà ôtô đi được tính từ lúc hãm phanh đến lúc dừng?

1 We have learned English for 10 years --> 2 It has been a long time since we last met . --> 3 Ms Ann has not taken part in any voluntary programs for 4 years --> 4 I have not met my family since last Christmas --> 5 How long have you lived here ? --> 6 The volunteers have provided free food and fresh water to homeless people since yesterday --> 7 The doctor has quitted his job in the local hospital and moved to the central hospital for 2 days --> 8 The children have not had a long vacation since last year --> 9 They have not visited their parents for 3 months --> 10 It has been 2 years since we broke up --> anh chị làm hộ em với em cần gấp vào sáng nay

Giải pt: a, 5(sinx-cosx)^2=cos4x+2 b, 2sin^2cos^2x-sin2x+1/2=0

Cho (P) y= x², lấy A(a; a²); B(b, b²); C (c; c²) thỏa mãn a²- b= b²- c= c²- a Tính T= (a+b+1)(p+ c+1)(a+c+1)

Tìm số tự nhiên a lớn nhất biết 612 chia hết cho a và 120 chia hết cho a