问题
填空题
设等差数列{an}的前n项和为Sn，则S4，S8-S4，S12-S8成等差数列．类比以上结论有：设等比数列{bn}的前n项积为Tn，则T4，______，
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答案
由于等差数列的定义是后一项减去前一项而等比数列的定义是后一项除以前一项
在运算上升了一级
故将差类比成比：
则T4，
，T8 T4
成等比数列T12 T8
故答案为
．T8 T4
搜题请搜索小程序“爱下问搜题”
设等差数列{an}的前n项和为Sn，则S4，S8-S4，S12-S8成等差数列．类比以上结论有：设等比数列{bn}的前n项积为Tn，则T4，______，
|
由于等差数列的定义是后一项减去前一项而等比数列的定义是后一项除以前一项
在运算上升了一级
故将差类比成比：
则T4，
，T8 T4
成等比数列T12 T8
故答案为
．T8 T4
| 阅读理解 | ||||||||||||||
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| 根据Fred 一周的活动安排，选择最佳答案。 | ||||||||||||||
| 1. Where does Fred meet Ann? | ||||||||||||||
| A. At Brown 's house. B. In the hospital. C. At the station. D. At Kay's house. | ||||||||||||||
| 2. For how many hours a week does Fred do his part time job? | ||||||||||||||
| A. Five hours. B. Six hours. C. Ten hours. D. Eleven hours. | ||||||||||||||
| 3. is ill in hospital. | ||||||||||||||
| A. Brown B. Joy C. Tom D. Kay | ||||||||||||||
| 4. Kay's birthday is on . | ||||||||||||||
| A. Tuesday B. Friday C. Sunday D. Thursday | ||||||||||||||
| 5. What does Fred do on Saturday afternoon? | ||||||||||||||
| A. Play football. B. Study with Tom. C. Have a dancing class. D. Do part time job. |