Cho tam giác ABC vuông tại A , đường cao AH . Chứng minh rằng 1/AH^2=1/AB^2+1/AC^2

Nêu các cách CM 3 điểm thẳng hàng và giúp mình làm bài dưới nhé 💞💞💞

Một con lắc lò xo dao động điều hòa với chu kì T và biên độ 5cm biết một chu kì khoảng thời gian để vật nhỏ của con lắc có độ lớn gia tốc không vượt quá 100 cm/s^2 là T/3 lấy pi^2=10 . Tần số dao động của vật là?

Effect tấm này cho mik '-' hoặc vẽ lại nó Y/C: - phải có layer - có chứ kí đàng hoàng - xấu = báo cáo -Dành cho dân gacha

Vì sao cây họ đậu cố định được đạm ? MN ơi giúp ppé vs ọ

III. Thể truyền khiến 1. I had my nephew paint the gate last week. 2. She will have Peter wash her car tomorrow. 3. They have her tell the story again. 4. John gets his sister to clean his shirt. 5. Anne had had a friend type her composition. 6. Rick will have a barber cut his hair. 7. I will get the dressmaker to make a new dress. 8. He had a mechanic repair his car. 9. She often gets the technician to maintain the heater. 10. They had the police arrest the shoplifter. 11. Are you going to have the shoemaker repair your shoes? 12. I must have the dentist check my teeth. 13. She will have a veterinary surgeon examine her dog. 14. We had a man take this photograph when we were on holiday last summer. 15. The Greens had a carpet cleaner clean their carpet. IV. Động từ khuyết thiếu 1. You can't wash this dress. →................................................................................................................. 2. You should open the wine about 3 hours before you use it. →................................................................................................................. 3. Members may keep books for 3 weeks. →................................................................................................................. 4. Passengers shouldn't throw away their tickets as inspectors (thanh tra) may check them during the journey. →................................................................................................................. 5. We shall have to tow (lai dắt) the car to the garage. →................................................................................................................. 6. Visitors must leave umbrellas (dù, ô) and sticks (gậy) in the cloakroom (phòng treo áo khoác). →................................................................................................................. 7. You should have taken those books back to the library. →................................................................................................................. 8. We cannot exchange articles (món hàng) which customers have bought during the sale. →................................................................................................................. 9. You mustn't move this man. He is too ill. V. Tổng hợp 1. People believe that 13 is an unlucky number. 2. They know that English is an international language. 3. I have heard her sing this song several times.. 4. People saw him steal your car. 5. They say that John is the brightest student in class. 6. Open your book. / let your book be opened 7. She advised me to sell that house. 8. It is dangerous for us to take the short cut.. 9. They think that he has died a natural death. … 10. He won’t let you do that silly thing again. 11. He orders us to clean the floor. 12. You must see it to believe it. 13. People believe that the earth stood still. 14. People don’t make the children work hard 15. Don’t do that silly thing again. 16. They begged us to help him 17. They will have to pull down that building. 18. They are going to hold next year’s meeting in New York. 19. He likes people to call him “Sir”. 20. My cousin will meet you at the station. 21. I found the book boring. 22. Peter advised me not to sell this flat. 23. She decided to paint her house blue. 24. My classmates used to call me John. 25. Mr.Brown will appoint Tom the director tomorrow. 26. You should pay more attention to you study. 27. He heard the bell ring. 28. I couldn’t catch any fish. 29. Did they build that house in 1972? 30. I like you to take photograph. 31. How did you break your leg? 32. She needs English for her work. 33. You must keep dogs outside shops. 34. Tom borrowed her book and lost it. 35. She used to make cloth puppets. 36. He saw you shopping. 37. Lan left her bag in the classroom. 38. I hear them singing a nice English song. 39. Everyone blieves him right. 40. I had him repair my watch. 41. We shall have a man cut the grass tomorrow. 42. Mai is going to have someone make her blouse. 43. They got him to take their suitcase upstairs. 44. I am going to get someone repaint my house. 45. People say that he is intelligent. 46. People say that he was intelligent. 47. People said that he was intelligent. 48. People say that she is good at English. 49. People said that they bought this shop last year. 50. They said that he could swim across the river. 51. They said that Mary was afraid of ghost. 52. People believed that the policeman had saved many children. 53. People said that the thief had stolen a lot of things. 54. People say that “David Copperfield” is an autobiography of Dickens’s. 55. You can’t wash this dress ; You must dry-clean it. 56. They considered the West End of London the world of the rich. 57. People know that Japan produces a wide range of cars. 58. People know that she was a famous singer. 59. Who wrote this novel? 60. People believe that he is the best football player in the world

0,21 < ........< 0,22 . CÁC SỐ ĐỀU có thể điền là A. 0,2 ;0,3 ;0,4 B . 0,211 ; 0,213 ; 0,2201 C. 0,212 ;0,216 ;0,2102 D .0, 210 ; 0,220 ;0 ,120 .mk cần gấp

vẽ đậu mầm lề :tui ko đủ điểm thi cấp 3 chỉ dự định tốt nghiệp vào học nghề vậy giờ tui rúi hồ sơ nộp vào trường nghề có đc ko :))

CHUYỂN CÁC CÂU SAU SANG CÂU BỊ ĐỘNG I. Động từ có 2 tân ngữ (Làm 2 cách) 1. Rachel will give you some advice. ……………………………………………. 2. I sent him a letter. ……………………………………………. 3. The police officer showed us the way. ……………………………………………. 4. Our neighbour gave me a lift. ……………………………………………. 5. She told me a lie. ……………………………………………. 6. They have written her a postcard. ……………………………………………. 7. Kerrie will make you a cup of tea. ……………………………………………. 8. The waiter has not brought us the coffee. ……………………………………………. 9. They did not offer her a seat. ……………………………………………. II. Bị động không ngôi (Làm 2 cách) 1. People know that she is a good swimmer. → ……………………………………………………………… → ……………………………………………………………………… 2. They say that Francis is in hospital. → ………………………………………………………………………… → ……………………………………………………………………… 3. They think that the children are in bed. → …………………………………………………………………………… → ……………………………………………………………………… 4. People believe that the robber has worked in the bank. → ………………………………………………………………………… 5. People believe that nuclear power stations are dangerous. → ……………………………………………………………………… → ……………………………………………………………………… 6. His collegues thought that he was on holiday. → ……………………………………………………………………… → ……………………………………………………………………… 7. People know that cars pollute the environment. → ………………………………………………………………………… → ……………………………………………………………………… 8. They suppose that the new product will come out soon. → ………………………………………………………………………… → ……………………………………………………………………… 9. They found that the mission was impossible. → ……………………………………………………………………………. 10. They believe that she will win a gold medal. → ……………………………………………………………………… → ………………………………………………………………………

Gần một giờ đêm. Trời mưa tầm tã. Nước sông Nhị Hà lên to quá, khúc đê thuộc làng X, thuộc phủ X, xem chừng núng thế lắm, hai ba đoạn đã thẩm lậu rồi, không khéo thì vỡ mất. Dân phu kể hàng trăm nghìn con người, từ chiều đến giờ, hết sức giữ gìn, kẻ thì thuổng người thì cuốc, kẻ đội đất, kẻ vác tre, nào đắp, nào cừ, bì bõm dưới bùn lầy ngập quá khuỷu chân, người nào người nấy lướt thướt như chuột lột. Tình cảnh trông thật thảm. Tuy trống đánh liên thanh, ốc thổi vô hồi, tiếng người xao xác gọi nhau sang hộ, nhưng xem chừng ai ai cũng mệt lử cả rồi. Ấy vậy mà trên trời thời vẫn mưa tầm tã trút xuống, dưới sông thời nước cứ cuồn cuộn bốc lên. Than ôi! Sức người khó lòng địch nổi với sức trời! Thế đê không sao cự lại được với thế nước! Lo thay! Nguy thay! Khúc đê này hỏng mất. Câu 1: Đoạn trích trên được viết theo phương thức biểu đạt nào? Câu 2: Chi tiết thời gian, địa điểm xảy ra sự việc được nêu trong đoạn trích trên có tác dụng: Câu 3: Dân phu trong đoạn trích trên đang lâm vào tình cảnh như thế nào? Câu 4: Các chi tiết trời mưa tầm tã trút xuống, nước sông cuồn cuộn bốc lên, dân phu ai ai cũng mệt lử ở đoạn trích trên được miêu tả bằng nghệ thuật gì?