在各项均为正数的等比数列{an}中,已知a2=2a1+3,且3a2,a4,5a3

题型:解答题

问题:

在各项均为正数的等比数列{an}中,已知a2=2a1+3,且3a2,a4,5a3成等差数列.

(1)求数列{an}的通项公式;

(2)设bn=log3an,求数列{anbn}的前n项和Sn.

考点:等比数列的定义及性质
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对下列疾病检查有意义的试验,鉴别甲、乙型血友病

A.纤维蛋白肽A测定
B.骨髓细胞学检查
C.简易凝血活酶生成试验
D.血小板抗体PAIgG检测
E.血小板黏附及聚集功能测定

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企业经营战略的特点有()。

A.纲领性

B.长远性

C.稳定性

D.竞争性

E.协调性

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用所给词的适当形式填空

1. My sister always_______(learn) language very quickly, but she isn't able to learm Greek.

2. When our teacher______( come) into the room, we  were talking.

3. I ________ ( be ) sixteen years old next year.

4. Jim and Kate______( marry) for 10 years.

5. The American friends_______( visit ) Beijing last spring.

6. By ten o'clock yesterday evening, they______( watch)TV for 12 hours.

7. Our teacher hoped that we______(succeed) some day .

8. The students _______( make) great progress in their spoken and writing English in the

last two months.           

9. My friend______( work) here since he graduated fromthe college.

10. Lily told me not to give up ______ ( study) English.

题型:解答题

现已建成的核电站发电的能量来自于 [ ]

A.天然放射性元素衰变放出的能量

B.人工放射性同位素放出的能量

C.重核裂变放出的能量

D.化学反应放出的能量

题型:解答题

我国的教育心理学最初是从西方引进的,__________年廖世承编写了我国第一本《教育心理学》教科书。

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