bo ngoac roi thu gon cac bieu thuc sau : a/ (a+b)-(a-b)+(a-c)-(a+c) b/ (a+b-c)+(a-b+c)-(b+c-a)-(a-b-c)

một vật có dao động điểu hòa với chu kỳ T = $\pi$ (s) và biên độ là 3cm. Li độ dao động là hàm sin gốc thời gian chọn vào lúc li độ cực đại .Phương trình vận tốc của vật theo tg có dạng là A. v=6cos(2t + $\pi$/2)cm/s B. v=6cos($\pi$t ) C. v=6$\pi$cos(2t + $\pi$/2)cm/s D. v=6$\pi$sin(2 $\pi$t )

tìm x biết a) 6x(x-2)+3x=6x²+10 b) (2x+1)(x-4)=(2x+1)²

Viết một bài văn ngắn nhất về kỳ nghỉ giáng Sinh của gia đình em bằng tiếng Anh

Huhu mình bị kẹt ai giúp mình với ạ, mình cảm ơn nhiều :(((

I. Sử dụng câu điều kiện loại I và loại II để viết lại câu 1. They don’t understand the problem. They won’t find a solution 2.  ……………………………… 3. Go right now or you’ll be late for the train.……………… 4. Because you speak English unnaturally, they do not understand you. 5.  ……………………… 6. We didn’t know your phone number, so we could not contact you. 7.  ………………… 8. Because Simon doesn’t live near his mother, he can’t visit her often. 9.  ……………………… 10. She didn’t hurry, so she missed the train.  ………………… 11. John is fat because he eats so many chips.  ………………… 12. Bill never does anything if you don’t tell him what to do.  Unless……… 13. They don’t have enough time so they cannot do me a favour.  ……………… 14. I must leave now, or I’ll miss the flight.  ……………… 15. Hurry up, or we will be late for the exam.  ……………… 16. Peter gets bad marks because he doesn’t prepare his lessons well  ……………… 17. He doesn’t apply for the job because he doesn’t have enough 18. qualifications. ………………… 19. We can’t buy this car because it is very expensive. . ………………… II. Rewrite the second sentence in such a way that it has the same meaning as the one before it: 1. You can’t visit the United States unless you get a visa If you don’t get a visa, you can’t visit the United States 2. We don’t go on holiday because we have enough money If we didn’t have enough money, we would go on holiday 3. What a pity you fail your driving test! I wish 4. I’m sorry I miss your birthday party I wish 5. Unless someone has a key, we can’t get into the house We can 6. He’s sorry now that he doesn’t invite Molly to his party He wishes 7. Unless he phones immediately, he won’t get any information If he 8. Mr. Will lost his job because he was late every day If Mr. Will 9. My husband doesn’t leave the car keys, so I can’t pick him up at the station If 10. He doesn’t hurry, so he misses the train If 11. We don’t go because it rains If 12. I’m sorry that I’m not finishing my homework now. I wish 13. The child will die if nobody sends for a doctor Unless 14. Susan feels sick because she eats 4 cream cakes If 15. Maria doesn’t apply for the job in the library and regrets it now Maria wishes 16. John is fat because he eats so many chips If John 17. It’s a pity I don’t take my doctor’s advice I wish 18. The accident happens because the train driver ignore a warning light If 19. We get lost because we don’t have a map If 20. Mrs. Taylor doesn’t like living in such a small house Mrs. Taylor wishes 21. If Joe doesn’t change his ways, he will end up in prison Unless 22. If he doesn’t work harder, he’ll lose his job Unless 23. Elizabeth get a bad cold because she starts smoking cigarettes If Elizabeth 24. Joan will stay on at school unless she finds a good job before September If Joan

Viết lại đoạn văn trong văn bản " Sống chết mặc bay "

2 bài ạ nhanh ạ giải thích chi tiết ạ

tìm giá trị nhỏ nhất của biểu thức A=3x²-7x

Ai giúp mik với mik hiện tại đag rất gấp mog có ng giúp