Bài 1: Chứng minh biểu thức sau có giá trị âm với mọi x,y a)A=-x^2-4y^2+2xy-12y-13

Cho em xin cách để học tốt Toán lớp 9 ạ, vì em thực sự rất yếu ở môn này luôn ạ! Em cũng bị áp lực bởi điểm số và em khá yếu ở phần áp dụng các công thức để thực hành. Em cảm ơn!

Câu 1 :Em cảm nhận như thế nào về buổi tựu trường mà tác giả miêu tả trong văn bản Tôi đi học Câu 2:Nhân vật bé Hồng trong văn bản “Trong lòng mẹ” cho em suy nghĩ gì về cuộc sống và tình cảm của con người trong xã hội phong kiến bấy giờ (nêu rõ định kiến về hủ tục: Góa chồng) Câu 3 :Nêu cảm nghĩ của em về hủ tục và định kiến “Góa chồng” của nhân dân ta thời xưa? Cần gấp ạ làm đc cảm ơn và vote 5*( làm tất cả )

II. Find ONE mistake in each of the following sentences and correct it. 1. Water pollute in the lake has made the fish die. A B C D 2. If I am you, I would choose another country to visit in this summer holiday A B C D 3. If the factory doesn’t stop pollute the lake, no fish will be able to survive. A B C D 4. Landslide has never occur in my region since 1995. A B C D 5. By the time I had went to India, I had known about its Holi festival of Colors A B C through my English book. D 6. If I save enough money for my Europe tour at the end of this year, A B I won’t waited until the next year to make it. C D 7. Lucy's brother told that he walked to school today. A B C D

Tìm tập xác định của hàm số sau Y=cot^2(2pi/3 - 3x)

Question I. Choose the best answer. (A,B, C or D ) 5. How long _____________ you studied English? A. have been B. have C. has D. having 6. The little cat should be _____________ to be healthy. A. cured B. cure C. cures D. curing 7. Disneyland is _____________ of the most interesting games. A. a house B. houses C. home D. homes 8. She wouldn't go out if she _____________ the weather forecast. A. listens to B. listened to C. listening to D. is listening to 9. My cousin said that she and her boyfriend would get_____________ in the following month. A. marry B. marries C. married D. marrying 10. Hoa told me that _____________ our new teacher of English. A. she wants to become B. she wanted to become C. she will become D. she wanted becoming 11. _____________ in science and technology have changed people's life dramatically. A. developing B. developed C. development D. developments 12. Stephen _____________me he'd bought that suit in a sale. A. said B. spoke C. told D. claimed 13. The little girl asked her father “ _____________ the dress for me?” A. You buy B. You would buy C. You will buy D. Will you buy 14. He suggested _____________ camping that Sunday. A. going B. goes C. went D. gone 15. Elie asked Stand_____________ to look at the new catalogue. A. did he want B. do you want C. if he wanted D. whether he wants 16. They said that we_____________ our houses and devices by our voice in the future. A. can adjust B. could adjust C. adjust D. will adjust 17. At 8 a.m. tomorrow, Janet_____________ a test on the importance of technology in the next 20 years. A. will be taking B. will being take C. take D. was taking 18. The librarian asked us _____________ so much noise. A. don't make B. not make C. not to make D. not making 19. She suggested that they _____________ her a birthday party. A. should give B. shall give C. would give D. will give

Bài 4: (1 điểm) Cho góc xOy = 130°. Oz là tia phân giác của góc ấy. Vẽ góc xOz đối đỉnh với góc xOz. Tính số đo yOz'. giúp mình vs ạ ;-; ;-; ;-; ;-;

30. He will take the dog out for a walk as soon as he dinner. A. finish B. finishes C. will finish D. finishing 31. I shall be glad when he A. had gone B. did go C. went D. has gone 32. Ask her to come and see me when she ___her work. A. finish B. has finished C. finished D. finishing 33. Turn off the gas. Don‟t you see the kettle ? A. boil B. boils C. is boiling D. boiled 34. Tom and Mary for Vietnam tomorrow. A. leave B. are leaving C. leaving D. are left 35. He always for a walk in the evening. A. go B. is going C. goes D. going 36. Her brother in Canada at present. A. working B. works C. is working D. work 37. I _______to the same barber since last year. A.am going B. have been going C. go D. had gone 38. Her father when she was a small girl. A. dies B. died C. has died D. had died 39. Last week, my professor promised that he today. A. would come B. will come C. comes D. coming 40. Pasteur in the 19th century. A. was living B. lived C. had lived D. has lived

Bài 1 TÌm x,y thỏa mãn a)x^2+y^2=4/x^2+9/y^2=0

Vẽ mầm vui Y/C : Không nhận tranh cũ NL : Thi xong oyy. Ai rảnh hongg zô chat cùng =))