数列
满足
,且
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/679401be6da078a518f95f9211dff17b.png)
____________
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c73f039d166c9bdc2ce65d930104b105.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2fd7e75832ae791087e27dee9f4405b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/679401be6da078a518f95f9211dff17b.png)
更新时间:2017-04-20 00:27:50
|
【知识点】 判断或写出数列中的项
相似题推荐
填空题-单空题
|
适中
(0.65)
解题方法
【推荐1】提丢斯—波得定则是关于太阳系中行星轨道的一个简单的几何学规则,它是1766年由德国的一位中学老师戴维·提丢斯发现的,后来被柏林天文台的台长波得归纳成一条定律,即数列
:0.4,0.7,1,1.6,2.8,5.2,10,19.6,…表示的是太阳系第n颗行星与太阳的平均距离(以天文单位A.U.为单位).现将数列
的各项乘以10后再减4得数列
,可以发现
从第3项起,每一项是前一项的2倍,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/414187fca31df508dbf88d7f2bb83662.png)
______ ,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c2f03f58e3c85de45bd3fd86a8a66f7.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](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/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/414187fca31df508dbf88d7f2bb83662.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c2f03f58e3c85de45bd3fd86a8a66f7.png)
您最近一年使用:0次
填空题-单空题
|
适中
(0.65)
【推荐2】已知数列
,
,…,
(
),按照
从小到大的顺序排列在一起,构成一个新的数列
:
,则
首次出现时为数列
的第______ 项.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/633d22853c65a3b97f7eb74afa8da9b1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32fc4ec73598f006b3199e07717110a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd30cf8105c43c653a7b7e165f256054.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cf5776ec7059c208daf01ca48a34915.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60d72e4652183e6999c972445e3ab407.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6a6b832d2922f5c5fea6a1143250f70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
您最近一年使用:0次