user-avatar
trangdoan0101
2 năm trước
cho a,b,c là các số thực dương thỏa mãn: a+b+c=3. chứng minh rằng: $4(a^2+b^2+c^2)-(a^3+b^3+c^3) ≥9$ mọi người làm theo phương pháp hệ số bất định ạ
Thích Trả lời Chia sẻ

Các câu hỏi liên quan

IV. Write the sentences with the cues given 1. you / scared / seeing / the dentist ? → 2. What / you I do / the last time I you/ have / bad / toothache ? → 3. Last week / the dentist / fill/ cavity I my tooth → 4. She / look / my teeth I and / tell / me I not/ worry. → 5. How often / you / brush / teeth ? → V. Write the second sentence so that it has a similar meaning to the first sentence 41. I always look after myself when my parents are away. → I always 42. What's the matter with you? → What's 43. Remember to brush your teeth before going to bed. → Don't forget 44. Don't forget to send me a postcard when you go abroad. → Remember 45. My school has more than 2,000 students. → There are VI. Write the second sentence so that it has a similar meaning to the first sentence 46. How is Hoa ______ now according to her Mom! ( difference ) 47. Loan was _______ because she got bad news. ( happy ) 48. Did you have an _______ with the director? ( appoint) 49. Minh looks _______ again. What's the matter with him? ( worry) 50. How do most ______ feel when they go to see a dentist ? ( child)

2018 © Loga - Không Ngừng Sáng Tạo - Bùng Cháy Đam Mê
Loga Team