4.2.1等差数列(1)
重点练
一、单选题
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A.15 | B.30 | C.31 | D.64 |
【知识点】 等差数列通项公式的基本量计算
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d9b9a88070caa083d5682fbb7607719e.png)
A.-24 | B.0 | C.12 | D.24 |
【知识点】 等比数列通项公式的基本量计算
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
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A.![]() | B.![]() | C.![]() | D.![]() |
【知识点】 判断或写出数列中的项 等差数列通项公式的基本量计算
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cfd121f4aeca8a78a320fca1fd1c4d07.png)
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A.![]() | B.![]() | C.![]() | D.![]() |
【知识点】 等差数列的简单应用
二、填空题
三、解答题
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(1)求证:数列{bn}为等差数列;
(2)求数列{an}的通项公式.
【知识点】 利用定义求等差数列通项公式