已知等比数列
的首项是1,公比为3,等差数列
的首项是-5,公差为1,把
中的各项按如下规则依次插入
的每相邻两项之间,构成新数列
:
,
,
,
,
,
,
,
,
,
,…,即在
和
两项之间依次插入
中n个项,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43b7e7cd571c8cd141cbbfe5d0890bf6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43b7e7cd571c8cd141cbbfe5d0890bf6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c88a7ef007c78a93e33bd77c4396626.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b715e7842b95f654f16056a7c7f2abe9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13423c094861baf4b759b7f3d8c3c226.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57483e04fd1840c87ac5325157149877.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c1ccc6c74b8754e9bcbb3f39a11b6f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a548938d87c80ac47910607d3857007f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f6714682274c31a328bf796e235900.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e64fcc69dc28bc11b22f5c9bec9e2aa1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daf464629fa321a6ff7401ab79f07083.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7e8aacaab35df64cdf30578fe78dbba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43b7e7cd571c8cd141cbbfe5d0890bf6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e036008e81bd371695d685068cd348e4.png)
A.1950 | B.1951 | C.1952 | D.1953 |
20-21高二上·陕西西安·期中 查看更多[2]
更新时间:2020-12-16 22:53:23
|
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【推荐1】满足
,
的数列
称为斐波那契数列,又称黄金分割数列.如图,依次以斐波那契数列
各项为边长作正方形,在每个正方形中取半径为该正方形边长、圆心角为90°的圆弧,依次连接圆弧端点所成的曲线被称为斐波那契螺旋线(也称“黄金螺旋”).下图圆心角为90°的扇形OAB中的曲线是斐波那契螺旋线的一段,若在该扇形内任取一点,则该点在图中阴影部分的概率为( )
![](https://img.xkw.com/dksih/QBM/2021/5/25/2728711584702464/2730622556577792/STEM/1c2b358c-9ea5-4ddb-9d2f-ba963d7bacac.png?resizew=217)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://img.xkw.com/dksih/QBM/2021/5/25/2728711584702464/2730622556577792/STEM/1c2b358c-9ea5-4ddb-9d2f-ba963d7bacac.png?resizew=217)
A.![]() | B.![]() |
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【推荐2】已知按规律排列的数列
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名校
解题方法
【推荐1】若两个等差数列
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
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【推荐2】设数列
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