x²+2(m-1)x+4m-11=0
Ta có: Δ=[2(m-1)]²-4.1.(4m-11)
=4(m-1)²-16m+44
=4m²-8m+4-16m+44
=4m²-24m+48
=(4m²-24m+36)+12
=4(m²-6m+9)+12
=4(m-3)²+12
Ta có: (m-3)²≥0
⇒4(m-3)²+12>0
⇒Phương trình luôn có 2 nghiệm phân biệt với∀m
Chúc bạn học tốt nhé! ^^
Đáp án:
Giải thích các bước giải:
PHUONG TRÌNH CÓ DEN TA phay LÀ ( m-1)''2-1.(4m-11)=m''2-6m+12 luon lớn hơn 0 do đó pt luôn có 2 nghiệm
tham khảo
IV. Choose the word or phrase among A, B, C or D that best fits the blank space in the following passage. COMMUNAL HOUSE (RONG HOUSE) The Rong House can only be (1)……….. in villages to the north of the Central Highlands, especially in Gia Lai and Kon Turn provinces. It is a large, imposing, beautifully decorated stilt house built (2)……….. in the middle of the village. It is where community activities (3)………..: meetings, wedding ceremonies, or playing ceremonies. It is also the place for for reception of guests. The Rong house of each ethnic group has its own architectural style, design, and décor. Yet there are shared (4)……….. In the village, it is often (5) ……….house roofed with yellow-dried thatch leaves and having 8 big wood columns. The rafters are decorated with patterns of bright colour, depicting religious scenes, legendary stories about ancient heroes, stylized animals, and other familiar things of the village life. The most distinction of the decor of the Rong House is the (6) ………. Of the brilliant God of Sun. The Rong House is a (7) ………of the culture of Central Highlanders, an age-old and stable culture. The bigger the house, the wealthier the village is. It is a (8) ………of the whole village. 1. A. found B. find C. to find D. finding 2. A. on B. in C. at D. under 3. A. happens B. take on C. take place D. occurs 4. A. features B.cultures C. customs D. designs 5. A. a big B. bigger C. biggest D. the biggest 6. A. portrait B. photo C. image D. painting 7. A. signal B. sign C. symbol D. scene 8. A. design B. pride C. proud D. respect
Cho x thuộc Z . Tìm giá trị nhỏ nhất của biểu thức A=/x/+7
Phần 1. Đoc câu tục ngữ sau và trả lời câu hỏi : Ăn quả nhớ kẻ trồng cây Câu 1. Câu tục ngữ đã sử dụng biện pháp tu từ nào? Cho biết hiệu quả nghệ thuật của phép tu từ đó trong việc thể hiện nội dung của câu tục ngữ. Câu 2. Viết từ 3 - 5 câu văn liên tiếp để chỉ ra nội dung và giá trị kinh nghiệm mà câu tục ngữ mang lại. Câu 3. Tìm 3 từ đồng nghĩa với từ "ăn". Câu 4. Ghi thêm 2 câu tục ngữ đã học có cùng chủ đề với câu tục ngữ trên
Cho 2 đọan thẳng Ab vs CD sao cho ab//cd ,Ab= CD Ch/minh ad=bc Ch/minh ad//bc
giúp em bài 6 với ạ làm được em vote cho 5 sao
67. We had a happy _______________ together. (CHILD) 68. My sister was very _______________ when her cat was run over by a car. (SET). 69. The air in the city is ________________ (POLLUTE) 70. An accident happened because of driving____________________ (CARE) 71. What's the____________________of this river? (DEEP) 72. I want to be a____________________when I finish school. (TRANSLATE) 73. Money doesn't usually bring____________________. (HAPPY) 74. We all enjoyed the trip. It was an____________________experience. (FORGET) 75. Do you have a good ___________ with your classmates? (RELATE) 76. Don't eat those vegetables. They're____________________ (POISON) 77. We’ll live a happier and __________ life if we keep our environment clean. (HEALTH) 78. Environmental ________ is everybody's responsibility. (PROTECT) 79. The price of ________ has gone up again. (ELECTRIC) 80. I'm very _______ of my father and love him so much. (PRIDE) 81. Tet is the most important ____________ for Vietnamese people. (CELEBRATE) 82. We must save the __________ resources. (NATURE) 83. The _____ of the earthquake in Japan in 1995 was terrible. (DESTROY) 84. The people in my home village are very helpful and _________________ (FRIEND). 85. Many ______ come to Ho Chi Minh's Mausoleum every day. (VISIT) 86. He will be very angry if we _________ with his ideas. (AGREE] 87. There was a look of_ _________ on her face when she heard the news. (SAD) 88. All _____ for the job must fill in the correct form. (APLLY) 89. I'd like to read ____ ___stories. (HISTORY) 90. His new book is full of __________ ideas. (CHALLENGE) 91. The students were _____________ prepared for the final exam. (CARE) 92. The careful preparation made the festival a great _____________________ (SUCCEED). 93. Although Titanic is a ____________ film, it has a sad ending. (ROMANCE) 94. ___________is still a major problem in most big cities. (POOR) 95. That's the _________ movie I have ever seen. (BAD) 96. An ____________ man has stolen all our money. (KNOW) 97. The keys were locked inside the car. _________________, a side window was open. (LUCKY) 98. What a _____________ day! (LOVE) 99. These shoes look quite smart but they're terribly ______________________ (COMFORT) 100. Women nowadays have more _______________ to participate in social activities. (FREE)
Tìm x,y . Giải cụ thể cho mik với ạ. Nhanh đúng mik cho 5 Sao.
Treo mọt vật nặng vào lò xo xoắn. Hỏi: a.Vật tác dụng vào lò xo một lực kéo hay lực đẩy? b. Kết quả tác dụng lực của vật lên lò xo làm lò xo sẽ như thế nào? c. Lò xo có tác dụng lực lên vật không? Lực đó là lực gì? d. Tại sao khi treo vật vào lò xo, vật không bị rơi xuống đất? Khi đó có cặp lực nào cân bằng không? Đó là những lực nào?
Tìm giá trị nhỏ nhất của biểu thức : A=|x|+7.
33. I’m full of____________________for my English teacher. (ADMIRE) 34. We can see a lot of____________________on TV every day. (ADVERTISE) 35. They used to live in a____________________area of the country. (MOUNTAIN) 36. It was the____________________storm they had ever had. (BAD) 37. He has caused his parents a lot of _______________ . (HAPPY) 38. We should learn all the ___________ verbs by heart. (REGULAR) 39. My sister speaks English ___________ . (FLUENT) 40. What is the correct __________ of this word? (PRONOUNCE) 41. He drove __________________ and had an accident. (CARE) 42. Do you think you get a good____________________at your school? (EDUCATE) 43. Reading books can improve our____________________. (KNOW) 44. I am fond of____________________stamps. (COLLECT) 45. Many people are made____________________after the storm. (HOME) 46. It was ___________ of him to leave the door open. (CARE) 47. My son wants to be an _____________ when he grows up. (ACT) 48. He used all his _____________ to open the door. (STRONG) 49. I can't stand his _____________ any more. (LAZY) 50. We were all ________________ at his success. (SURPRISE) 51. _______________, he failed his exam. (LUCK) 52. They used to be ______________ . (CLASS) 53. His at the party embarrassed everyone. (BEHAVE) 54. Remember to check for ______________ mistakes before handing your test. (SPELL) 55. Read the text and _____________ any words you don't understand. (LINE) 56. Our English lessons always begin with a______________________drill of the new words. (PRONOUNCE) 57. A fairy appeared and______________________changed her old clothes. (MAGIC) 58. The children enjoy_____________________around the fields, shouting and laughing. (RUN) 59. The hills are________________in spring when the wild flowers are in full bloom. (COLOR) 60. Her mother soon died of a______________________heart. (BREAK) 61. Carving egg shells is a __________ way of spending time. (WONDER) 62. That boy can use leaves to make __ sound [MUSIC] 63. We can buy sports _____________ at the shop over there. [EQUIP] 64. There was great________all over the country when our team won the Football Cup. (EXCITED) 65. Every in my neighborhood has at least one TV set. [HOUSE] 66. This river is very _______________ for swimmers. (DANGER)
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