Đáp án + Giải thích các bước giải:
Đặt `A = 4 - (x - 55)^22`
Vì `(x - 55)^22 \ge 0` với mọi x
`=> 4 - (x - 55)^22 \le 4` với mọi x
Dấu "=" xảy ra khi:
`(x - 55)^22 = 0`
`=> x - 55 = 0`
`=> x = 0 + 55`
`=> x = 55`
Vậy GTLN của `A` là `4` tại `x = 55`
`4-(x-55)^22`
Ta có:
`(x-55)^22>=0∀x`(22 là số mũ chẵn)
`=>-(x-55)^22<=0∀x`
`=>4-(x-55)^22<=4∀x`
`(x-55)^22=0`
`=>x-55=0`
`=>x=55`
Vậy giá trị lớn nhất của biểu thức là `4` khi `x=55.`
Dựa vào hình dung và tưởng tượng của bản thân, hãy viết đoạn văn ( khoảng 8 – 10 câu) miêu tả những âm thanh trong cuộc sống mà em yêu quý. Giúp mình không chép trên mạng nha!
Write a short paragraph a about how to plant sunflowers NL dùng sequence adverb nha Mik cmr ơn trước
31. I couldn’t do the test because it was difficult. >> Because of…………………………………………………………………………… 32. I couldn’t read the letter because it was dark. >> Because of…………………………………………………………………………………… 33. I can’t study because it is noisy. >> Because of…………………………………………………………………………………… 34. The train come late because it was foggy. >> Because of…………………………………………………………………………………… 35. The train was late because the fog was thick. >> Because of…………………………………………………………………………… 36. I can’t sleep because the weather is hot. >> Because of…………………………………………………………………………………… 37. All the teacher love him because his conduct is good. >> Because of……………………………………………………………………… 38. Because there was a traffic accident, I went to school late. >> Because of……………………………………………………………………………… 39. Because there is a shortage of meet, we had to live on beans. >> Because of……………………………………………………………………… 40. Because there was a lack of water, many trees died rapidly. >> Because of……………………………………………………………………………………………… 41. She walked slowly because her leg was injured. >> Because of…………………………………………………………………
Exercise 2. Put in the present perfect or past simple of the verbs in brackets. 1. Martin (be) ________ to Greek five times. He loves the place. 2. I (work) ________ for a computer company for a year. That was after college. 3. We (move) ________here in 1993. We (be) ________ here a long time now. 4. It isn’t a very good party. Most people (already/ go) ________ home. 5. It was so hot today that I (wear) ________ shorts and a T-shirt at work. 6. My wife and I (move) ________ three times since we (get) married. 7. So far this week there (be) ________ three burglaries in our street. 8. When I was younger I (play) ________ badminton for my local team. 9. In the past few years, it (become) ________ more and more difficult to get into university. 10. I (enjoy) ________ skiing ever since I (live) ________ in Switzerland. 11. I (not see) ________ Rachel for ages. She (not visit) ________ us since July.
mọi người ơi, giải hộ mk vs ạ, mk cảm ơn
Mình đang cần gấp giúp mình với ạ , xin cảm ơn nhiều ạ^^
yêu cầu tạo logo có: lớp 8a2 chất chơi thcs Nguyễn Trực-TT Kim có màu hình tròn đẹp kiểu ảo tạo bằng máy tính
giải nhanh giúp mình nha, cần gấp 4 giờ 30 đi học rồi ạ
16. Despite a good salary, he was unhappy in his job. >> Though………………………………………………………………………………………………. 17. In spite of the high prices, my roommates go to the movies every Saturday. >>Although…………………………………………………………………………. 18. Even though she had a poor memory, she told interesting stories to the children. >>Despite…………………………………………………………………………………. 19. In spite of their poverty, they are very generous. >> Although………………………………………………………………………………. 20. Though she has been absent frequently, he has managed to pass the test. >> Despite……………………………………………………………………………………………… 21. In spite of Lee’s Sadness at losing the contest, she managed to smile. >> Although………………………………………………………………………………… 22. My friend ate the chocolate cake even though she was on a diet. >>Despite………………………………………………………………………… 23. In spite of a headache, he enjoyed the film. >> Although……………………………………………………………………………… 24. My sister will take a plane even though she dislikes flying. >>In spite of……………………………………………………………………………… 25. He isn’t happy although he is very rich. >>Despite……………………………………………………………………………… 26. Even though he got a good job, he was not satisfied. >> Despite………………………………………………………………………… 27. Although he often tells lies, many people believe him. >> Despite……………………………………………………………………………… 28. Mary didn’t go to school yesterday because she was sick. >> Because of………………………………………………………………………… 29. She went to bed early because she felt tired. >>Because of………………………………………………………………………… 30. Margaret stayed at home because her mother was sick. >> Because of…………………………………………………………………………
E. The past progressive tense : 65. I was studying my English lesson last night -> 66. They weren’t writing Lenin’s words on the poster -> 67. We were playing football when it rained -> 68. Mary was talking to John when I saw them -> 69. Was the mailmain delivering the mails then ? -> 70. Police were holding him for further questioning -> 71. Were they studying Mathemastics then ? -> 72. They weren’t asking me many difficult questions ->
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