Bài 1: Biến đổi biểu thức sau : A= ( x+5y ) ² - ( 2x - 7y ) ² Bài 2: Rút gọn biểu thức : a) ( x + y ) ² + ( x - y ) ² b) 2 ( x + y ) ( x - y ) + ( x + y ) ² + ( x - y ) ² Bài 3: Tính nhanh : a) 34 ² + 66 ² + 68 . 66 b) 74 ² + 24 ² - 48. 74 Bài 4: Tính giá trị của biểu thức: a) x ² + 4x + 4 tại x = 98 b) x ³ + 3x ² + 3x +1 tai x = 99 MN giúp e vs ak. E cảm ơn trc ạ.

Hai đơn vị A và B sản xuất 3600 chai nước sát khuẩn trong hai ngày. Nếu làm riêng thì đội A làm xong trước đội B 3 ngay. Hỏi nếu làm riêng thì mỗi đội làm xong trong bao lâu? Giúp mình với mai mình thi tuyển sinh rồi

Giải mình câu này chi tiết nhất có thể

Cho phương trình x^2 - 2(m - 1) - 4m - 4 = 0 a) Chứng minh rằng phương trình luôn có hai nghiệm phân biệt x1, x2 với mọi giá trị của m. b) Tìm m để |x1 - x2| đạt giá trị nhỏ nhất. Mn làm câu b thôi nha. Mình cảm ơn !

A. Choose the right word or phrase best completes the sentence: 1. Three weeks _______not enough holiday. ​A. are​​B. were​​C. was​​​D. been 2. Each of you ____ a share in the work. ​A. having ​B. has ​​​C. to have​​ D. have 3. A number of students ____ volunteered to the job. ​A. have ​​B. has ​​​C. to have ​​D. having 4. Linguistics ____ out the ways in which languages work. ​A. find ​​B. finding ​​C. to find ​​D. finds 5. The Philippines ____ of more than 7,000 islands. ​A. consist ​B. consisting ​​C. consisted ​​D. consists 6. The United Nations ____ its head quarters in NewYork city. ​A. have ​​B. having ​​C. has​​ ​D. to have 7. One of my neighbours ____ curious about other people’s private life. ​A. being ​​B. were ​​C. is ​​​D. been 8. Tom doesn’t agree but the rest of us ____. ​A. does ​​B. done ​​C. do ​​​D. doing 9. There ____ a few flowers in this garden last summer. ​A. being ​​B. were ​​C. are ​​​D. is 10. A large number of reporters ____ at the meeting yesterday. ​A. being ​​B. were ​​C. are ​​​D. is 11. Much progress ____ been made in recent years. ​A. have ​​B. has ​​​C. having ​​D. to have 12. Collecting old coins and paper notes ____ one of my hobbies. ​A. being ​​B. were ​​C. are ​​​D. is 13. The number of pupils getting poor marks since the beginning of the semester ____ appalling. ​A. to be ​​B. have been ​​C. are​​ ​D. is 14. Five thousand pounds ____ stolen in the robbery last night. ​A. being ​​B. were ​​C. are ​​​D. was 15. Mr. Thomson with his wife and his three children ____ abroad. ​A. to be ​​B. have been ​​C. are ​​​D. is 16. One of the girls who ____ working in this department ____ my niece. ​A. is/being ​B. are/is ​​C. is/are ​​D. was/were 17. The English ____ to drink tea. ​A. likes ​​B. to like ​​C. like ​​D. has liked 18. Everybody ____ trying to do their best at present. ​A. to be ​​B. have been ​​C. are ​​​D. is 19. Jim as well as I ____ always busy doing English homework. ​A. am ​​B. has been ​​C. are​​ ​D. is 20. Neither Daisy nor I ____ glad to do that. ​A. am ​​B. has been ​​C. are ​​​D. is 21. That you take a computer course ____ very necessary. ​A. am ​​B. have been ​​C. are ​​​D. is 22. The police ____ come to the site of the accident. ​A. have ​​B. has ​​​C. having ​​D. to have 23. The pilot along with his passengers ____ rescued last night. ​A. am ​​B. have been​ ​C. was ​​D. is 24. What we need most ____ books. ​A. is ​​B. were ​​C. are ​​​D. to be 25. My brother together with his friends often ____ in the park. ​A. jogs ​​B. jogging ​​C. jog ​​​D. to jog 26. Neither he nor they ____ here yesterday. ​A. are ​​B. were ​​C. is ​​​D. be 27. Either John or his children ____ breakfast each morning. ​A. make ​​B. makes ​​C. making ​​D. to make 28. I don’t like the hot weather. Thirty degrees ____ too warm for me. ​A. was ​​B. are ​​​C. being ​​D. is 29. Not only a dog but also two cats ____ at home in his garage. ​A. was ​​B. are ​​​C. been ​​D. is 30. Both a poem and a short story ____ been written by the young author. ​A. has ​​B. to have ​​C. have ​​D. having Làm + giải thích giúp mik Vẫn còn sớm đừng ngủ vội giúp mik nhé (• ε •)(• ε •)(• ε •)

giúp e vs ạ thanks nhiều ạ giải chi tiết nha

Cho đoạn thẳng AB dài 12 cm, lấy điểm C nằm giữa A và B sao cho BC = 6 cm. a) Tính độ dài đoạn thẳng AC b) Điểm C có là trung điểm của đoạn thẳng AB không? Vì sao? c) Lấy điểm M nằm giữa A và B ( điểm M khác điểm C ). Gọi E và F lần lượt là trung điểm của AM và BM. Tính độ dài đoạn thẳng EF

40. Mother: Your face is dirty. Child: All right, I _______ ( wash) it. 41. I’ve hired a type writer and I ________ (learn) to type. 42. I________ (work) for Mr. Pitt next week as his own secretary will be away. 43. Do you think that you ______________(pass) your exams in June. 44. At this time tomorrow we ______ (fly) over the Atlantic. 45. By the time I go to bed tonight, I____________( finish) my work for the day. 46. A: I don’t feel well enough to go to the station to meet him. B: I ____________(meet) him for you. But how _________(recognize) him? A: He’s small and fair, and he ________ (wear) a black and white school cap. 47. He ____________ (live) in this city for exactly two years by next Monday. 48. I’m turning this cupboard into a darkroom. I_______ (develop) my own films. 49. “ If you don’t pay the ransom, we’ll kill your boy” the kidnappers told us. à The kidnappers threatened _________________________________________. 50. She promised to come round and see me everyday. à She said, “ I will _________________________________________________.” Các bạn giúp mik làm với Làm xong mik cần lời giải thích từ các bạn 😭😭😭

Khoanh tròn đáp án đúng và giải thik ạ

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