Phương trình bậc hai có hai nghiệm là 1 + 2i và 1 - 2i có dạng:
A. x2 - 2x - 3 = 0
B. x2 + 4ix + 5 = 0
C. x2 + 2x - 5 = 0
D. x2 - 2x + 5 = 0

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Read the passage below and choose one correct answer for each question:
        My name is Seumas McSporran and I’m a very busy man. I’m 60 years old and I have thirteen jobs. I am a postman, a politician, a fireman, a taxi driver, a school-bus driver, a boatman, an ambulance man, an accountant, a petrol attendant, a barman, and an undertaker. Also, I and my wife, Margaret, have a shop and a small hotel.       I live and work on the island of Gigha in the west of Scotland. Only 20 people live there but in summer 150 tourists come by boat every day.       Every weekday I get up at 6.00 and makes breakfast for the hotel guests. At 8.00 I drive the island’s children to school. At 9.00 I collect the post from the boat and deliver it to all the houses on the island. I also deliver the beer to the island’s only pub. Then I help Margaret in the shop.       My wife likes being busy. too. We never have holidays and we don’t watch television. In the evenings Margaret makes supper and I do the accounts. At 10.00 we have a glass of wine and then we go to bed. Perhaps our life isn’t very exciting, but we like it.
 
1. Mr. McSporran does all the following jobs EXCEPT .A. a firefighter             B. a driver                   C. a farmer                D. a mailman
2. Giaha is the name of ______________A. his wife                                        B. his hotelC. the shop where they work          D. the island where they live
3. Tourists _____________ to the island.A. sail                B. fly                 C. swim                  D. drive
4. The word “it” in paragraph 3 refer to ________________.A. beer              B. post             C. boat                    D. pub
5. According to the passage which is true about Seumas McSporran?A. He likes the job as a postman most.B. He and his wife go on holiday every year.C. He does the accounts in the evening.D. He goes to bed very late.
 
A. 1. C             2. D                  3. A                  4. B                5. D
B. 1. C             2. D                  3. A                  4. B                5. C
C. 1. C             2. D                  3. B                  4. B                5. C
D. 1. C             2. D                  3. A                  4. D                5. C