a)Tìm GTNN của 1)D=|x-1|+|x-2|+|x-3|+|x-4| 2)E=|x+1|+|x+2|

Giúp mình bài này với Đề bài là tìm x nha

tách riêng từng kim loại nguyên chất ra khỏi hh mgco3,k2co3,baco3

cho : `x;y≥0` `x+y=1` tìm `maxA=(x)/(y+1)+(y)/(x+1)`

Cho 19,2 gam hỗn hợp X gồm Fe và Ag tác dụng với dung dịch H2SO4 loãng dư thì thu được 3,36 lít khí H2 (đktc) a) Tính phần trăm khối lượng mỗi kim loại trong hỗn hợp X b) Nếu cho 19,2 gam hỗn hợp trên tác dụng với dung dịch H2SO4 đặc, nguội dư thì thu được V lít khí SO2 (đktc) và dung dịch chứa m gam muối. Tìm giá trị V và m

làm phần nào cũng được, giúp mình với sáng mai mình học rồi Choose the one word or phrase -a, b, c, or d- that best completes the sentences. 16. If the technology _______ available, we would be able to expand the business. a. would become b. were become c. had become d. Became 17. If the North Sea _______ in winter, you could walk from London to Oslo. a. happened to freeze b. froze c. should freeze d. should happen to freeze 18. It would have been a much more serious accident _____ fast at the time. a. was she driving b. had she been driving c. she had driven d. if she drove 19. If you _______ to my advice in the first place, you wouldn't be in this mess now. a. listen b. will listen c. had listened d. listened 20. I'll give you a lift if it _______. a. is raining b. rained c. will rain d. had rained 21. If I _______ a more reliable car, I ' _______to Spain rather than fly. a. would have - would drive b. had - had driven c. had - would drive d. would have had - would drive 22. I _______ you sooner had someone told me you were in the hospital. a. would have visited b. had visited c. visited d. visit 23. They couldn't decide _______ it was worth re-sitting the exam. a. if b. whether c. if or not d. whether not 24. _______ how difficult the job was, I mightn't have taken it. a. If I know b. If I would know c. Did I know d. Had I known 25. ____ in my seventies and rather unfit, I might consider taking up squash. a. Were I not b. Was I not c. Weren't I d. If I am not C. Identify the one underlined word or phrase -A, B, C or D-that must be changed for the sentence to be correct. 26. Some scientists believe that the earth have resources enough A B to support its population. C D 27. The population of the world has been increased faster and faster. A B C D 28. Ninety-seven percent of the world' water is saltwater is found in A B C the oceans of the Earth. D 29. Hadn't he resigned, we would have been forced to sack him. A B C D 30. John lived in New York since 1960 to 1975, but he is now living in Detroit. A B C D

41) The man about ____ I was telling you is standing over there. A. who B. that C. whom D. All are correct 42) The woman ____ Ann must take care of is very poor and old. A. whom B. that C. who D. All are correct 43) This is the man to ____ I gave some money this morning. A. who B. whom C. that D. All are correct 44) This is the result of our work ____ I’m pleased with. A. that B. whose C. which D. A & C are correct 45) The problem in ____ we are very interested has been discussed in class. A. that B. whom C. which D. A & C are correct 46) The boy ____ you made fun of yesterday is my cousin. A. who B. whom C. that D. All are correct 47)Ann, ____ lives next door, is very friendly. A. who B. whom C. that D. All are correct 48) We went to Sandra’s party, ____ we enjoyed very much. A. which B. whom C. that D. who 49) John, ____ I have known for a very long time, is one of my closest friends. A. whose B. whom C. that D. B & C are correct 50) Sheila, ____ job involves a lot of travelling, is away from home a lot. A. whose B. whom C. that D. which 51) This new stadium, ____ can hold 90,000 people, will be opened next month. A. that B. whose C. which D. A & B are correct 52) My brother, ____ lives in Houston, is a doctor A. who B. whom C.that D. A & B are correct 53) My office, ____ is on the second floor, is small. A. whose B. which C. who. .D. A & B are correct 54) She told me her address ____ I wrote down on a piece of paper. A. which B. that C. whose D. A & B are correct 55) The sun, ____ is one of millions of stars in the universe, provides us with heat and light. A. which B. that C. who D. A & B are correct 56) Tom made a number of suggestions, most of ____ were very helpful. A. them B. which C. that D. B & C are correct 57) Mary has three brothers, all of ____ are married. 60) The meeting ………I went was interesting. A. to which B. which C. that D. B & C are correct 58) We were given a lot of information, most of ____ was useless. A. which B. it C. that D. All are correct 59) There were a lot of people at the party, only a few of ____ I had met before. A. them B. whom C. who D. B & C are correct 60) I sent her two letters, neither of ____ she has received. A. that B. these C. which D. whom

Tìm x để $\frac{2\sqrt x}{x - \sqrt x +1}$ nhận giá trị nguyên

1 What is the typical diet of people in your country? 2 How are the eating habits now in your country different from eating habits in the past? 3 What's the difference between restaurant food and home-cooked food? 4 Why do you think people eat junk food when they know it's bad for them?

1) Cmr biểu thức sau ko phụ thuộc vào biến (2x-9).(2x+1)-(4x-3).(x+2)+5(x+3)