已知数列
中,
,数列
中,
,且点
在直线
上.
(1)求证数列
为等比数列,并求数列
和数列
的通项公式;
(2)若
,求数列
的前项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/229b20a8cd81bb56376db3de54d33390.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59dd6c97d2ee3e74ba5730f1cbcc1d43.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fefb5ee4a29f150b79adcb3a65efad87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e6e15daf7b14dbff32c390f4984dcfb.png)
(1)求证数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebf1249cf2944377c0b095a6728fdae4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a933e57692c6817d23dc221e2e50e3fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ff530320a228db7b1a3639f925013ae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
更新时间:2020-11-14 16:00:04
|
相似题推荐
解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐1】已知数列
的前
项和为
,
,
(
),其中
.
(1)判断数列
是否为等比数列,并说明理由;
(2)已知集合
,是否存在正实数
,使得对一切
,均有
,若存在,求出
的取值范围,若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7fab51121848ce166035ceab6f4e00b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19c5ae82adc8517529456f4695409e70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db54a9493894207b0f9c6d61deef1fd1.png)
(1)判断数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)已知集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e433da4dac37412ed73a508d3299d65e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35eb4fe67d5a6378c3ac14def93d0d8d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
您最近一年使用:0次
【推荐2】已知数列
满足
记数列
的前
项和为
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d94143fb589b2640d2aa2ed58f6014e.png)
(1)求证:数列
为等比数列,并求其通项
;
(2)求
;
(3)问是否存在正整数
,使得
成立?说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d0a6b89704abb88cfa1bd43e7ae192f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/276d9598998e194683b7608f1012f806.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d94143fb589b2640d2aa2ed58f6014e.png)
(1)求证:数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/686ece75006ad358f23314dc8a246e11.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
(3)问是否存在正整数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6f591133b4e75df5e815f10ec96dd47.png)
您最近一年使用:0次
【推荐1】已知数列
满足
,
.
(1)求数列
的通项公式;
(2)记数列
的前
项中最大值为
,最小值为
,令
,称数列
是数列
的“中程数数列”.
①求“中程数数列”
的前
项和
;
②若
(
且
),求所有满足条件的实数对
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d9eccf018a2701fccae54587d5209d11.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
(2)记数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ddad3d9fdb5e9951b6a1c31f9a72a71.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0a625b91e0eba33b107550ee2a1e2f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/293570f1284f5161d0c9e83c1aef7777.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43b7e7cd571c8cd141cbbfe5d0890bf6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
①求“中程数数列”
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43b7e7cd571c8cd141cbbfe5d0890bf6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
②若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e195bfeee892169b583158ad2363f5f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/faf534a50982614f697e616657822285.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4c428c12bd1ab65b447a57547b33302.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/865f61c8bbe153f7010bcc28a9ebf462.png)
您最近一年使用:0次
【推荐2】已知数列
满足
,且
且
.
(1)求数列
的通项公式;
(2)设数列
的前n项之和
,求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11258a5e265830baf230f151786c5a75.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1717bfd39e7c7263ffd3e55c15c04f18.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)设数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
您最近一年使用:0次