Cho pt: -mx^2 + (2m+3)x - m+1 >0 Tìm m để : a,Bất pt có nghiệm ? b,Bất pt có nghiệm với mọi x ? Mọi người giúp em với em đang cẩn gấp ạ

rút gọn đa thức sau m.n giải đầy đủ nha hứa vote 5 sao M = y^2 -2*y + 1 /2*y^2 +5*y - y^2

TRong câu "Những vòm lộc non đg đung đưa kia vẫ ru tôi nhè nhẹ trở lại quê nhà trong thoáng chốc " đâu là bộ phận vị ngữ

Tam giác cân có hai cạnh là 12cm và 5cm. Chu vi của tam giác là: ????????cm

Dẫn V lít (đktc) hỗn hợp khí X gồm etan C2H6, etilen C2H4và metyl axetilen C3H4 đi qua dung dịch AgNO3/NH3 dư thấy xuất hiện 2,94 gam kết tủa màu vàng và thoát ra hỗn hợp khí Y. Tiếp tục dẫn khí Y đi qua 3 dung dịch brom dư thấy bình đựng dung dịch brom tăng 0,42 gam và thoát ra khí Z duy nhất. Tiến hành đốt cháy hết khí Z bằng O2 được 3,36 lít khí CO2 (đktc). a/ Tính giá trị V ? b/ Tính thành phần % về thể tích mỗi chất trong hỗn hợp X.

Cac bn giải hộ mình 2 bài này vs ạ, k chép mạng nha mọi người . Mình đang cần gấp ạ

Ném quả bóng từ điểm A lên cao như hình vẽ a) Ở vị trí nào quả bóng có thế năng lớn nhất ? thế năng nhỏ nhất ? động năng nhỏ nhất ? b) Cho biết sự chuyển hóa các dạng của cơ năng khi quả bóng đi từ A đến B , từ B đến C

Giúp em bài tập làm văn em vote 5 sao+30 điểm

nêu cảm nhân Tôi lại về quê mẹ nuôi xưa Một buổi trưa, nắng dài bãi cát Gió lộng xôn xao, sóng biển đu đưa Mát rượi lòng ta ngân nga tiếng hát

2. Hello, I___________ about your advertisement in the newspaper. A. Have been calling B. am calling C. call D. have called 3. John___________ on a bit of weight lately, and he is trying to lose it. A. Puts B. is putting C. has put D. has been putting 4. The new neighbors_________ their house. It looks nice. A. Paint B. had painted C. were painting D. have painted 5. Fred__________ me yesterday that they're professional athletes. A. Told B. has told C. was telling D. had told 6. Apparently, he_________ them since he was a child. A. Knows B. is knowing C. has known D. has been knowing 7. I__________ for my sunglasses since noon, but I can't find them. A. Am looking B. looked C. have looked D. have been looking 8. When the children_________home, it was obvious that they had been playing in mud. A. Arrived B. were arriving C. had arrived D. had been arriving 9. Michael___________in the queue to buy a ticket for the train when he heard a strange voice. A. Waited B. was waiting C. had waited D. was going to wait 10. The thieves_______ houses for two years before they were finally caught. A. Broke into B. were breaking into C. had been breaking into D. have been breaking into 11. As time goes by, he__________more and more eccentric. A. Becomes B. is becoming C. has become D. has been becoming 12. Kathy can't go shopping with me next Saturday morning. She_________a French lesson. A. Has B. is going to have C. will have D. will be having 13. I__________ the living room by the time Dad comes home. He__________ so surprised. A. Will paint/will be B. will be painting/is C. will have painted/will be D. will have painted/is 14. It's the coldest winter we__________ in Greece. A. Ever experience B. ever experienced C. were ever experiencing D. have ever experienced 15. When he___________ was younger, he the cinema every week. A. Was used to going B. used to go C. was going D. had gone 16. They________for a mile when they___________that someone___________missing. A. Had walked/ had realized/ was B. had been walking/ realized/ had been C. had been walking/ realized/ was D. had walked/ had realized/ had been 17. As part of my job, I_________ abroad a lot, so I_______ to improve my English. A. Travel/ need B. am travelling/ need C. am travelling/ am needing D. travel/ am needing 18. I_________ at my mother's house this week because I__________ my house painted. A. Sleep/ have B. am sleeping/ have C. sleep/ am having D. am sleeping/ am having 19. I you should buy him a tie. He___________to dress formally. A. Am thinking/ likes B. think/likes C. think/ is liking D. am thinking/ has liked 20. As a teenager, I_________ things my parents__________ of. A. Would do/ didn't approve B. used to do/ weren't approving C. used to do/ didn't approve D. would do/ weren't approving