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hoangnamfc2001
2 năm trước
Chứng minh: $\frac{1}{9}$[ 3k(3k+3)(3k+6) - 3k(3k-3)(3k+3)] = 3k(3k+1) . Giúp mình nhá^^
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Exercise 114. Choose one word or phrase marked A, B, C, or D that best complete the preceding sentence. 1. “Would you like to go for a walk along the beach?” A. Joe asked me whether I felt like to go for a walk along the beach. B. Joe asked me if I felt to like to go for a walk along the beach. C. Joe asked me if I felt like going out for a walk along the beach. D. Both A and C 2. He asked the children _____________too much noise. A.not to make B. not making C. don’t make D. if they don’t make 3. The man said that the days _____________longer in summer. A.will be B. are C. were D. can be 4. “Do you know what time the Classical music performance begins, Anna?” asked John. A. John asked Anna to know what time the Classical music performance begins. B. John asked Anna what time did the Classical music performance begin. C. John asked Anna if she knew what time the Classical music performance began. D. John asked Anna if she had known what time the Classical music performance began. 5. The teacher said Columbus_____________ America in 1942. A.discovered B. had discovered C.was discovering D. would discover 6. “Be careful! Don’t do that again,” he said. A. He encouraged me to do that again. B. He advised me to be careful and do that again. C. He warned me not to do that again. D. He told me to be careful, so I didn’t do that again. 7. John said he_____________ her since they____________ school. A.hasn’t met/ left B. hadn’t met/ had left C.hadn’t met/ left D. didn’t meet/ has left 8. She asked John to repeat what he had said. A. “Will you please repeat what John said?” she asked. B. “Please repeat what you said, John,” she said. C. “You have to repeat what you say, John,” she said. D. “Please repeat what you said to John,” she said. 9. The woman asked_____________ get lunch at school. A.can the children B. whether the children could C.if the children can D. could the children 10. “No, it’s not true. I didn’t steal the money!” Jean said. A.Jean refused to steal the money. B. Jean did not intend to steal the money. C.Jean admitted stealing the money. D. Jean denied having stolen the money. 11. Laura said that when she_____________ to school, she saw an accident. A.was walking B. has walked C.had been walking D. has been walking 12. “Why don’t we go out for dinner?” said Mary. A.Mary suggested a dinner out. B. Mary ordered a dinner out. C.Mary demanded a dinner out. D. Mary requested a dinner out. 13. He asked, “Why didn’t she take the final exam?” – He asked why__________ the final exam. A.she took B. did she take C.she hadn’t taken D. she had taken 14. Ba said he______________ some good marks last semester. A.gets B. got C. getting D. have got 15. My friend told me, “If I were you, I would not smoke so much.” A. My friend advised me not to smoke so much. B. My friend warned me against smoking so much. C. My friend prohibited me from smoking so much. D. My friend suggested not smoking so much. 16. They told their parents that they_______________ their best to do the test. A.try B. will try C. are trying D. would try 17. “I will let you know the answer by the end of this week,” Tom said to Janet. A. Tom suggested giving Janet the answer by the end of the week. B. Tom promised to give Janet the answer by the end of the week. C. Tom insisted on letting Janet know the answer by the end of the week. D. Tom offered to give Janet the answer by the end of the week. 18. She asked me where I_______________ from. A.come B. coming C. to come D. came 19. She_____________ me whether I liked classical music or not. A.ask B. asks C. asked D. asking 20. “Why didn’t you follow my advice?” he said. A. He asked me to follow his advice. B. He asked me not to follow his advice. C. He asked me why I did follow his advice. D. He asked me why I hadn’t followed his advice.

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