1 . 设数列
的前
项和
,若
,
,则
的通项公式为_____ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.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/bbe7bdaaf8b0adf10bf2ef6c1255b1dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c720d4670b9c336b94439caed893b982.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
您最近一年使用:0次
2019-07-08更新
|
1277次组卷
|
3卷引用:上海市闵行区七宝中学2018-2019学年高一下学期期末数学试题
名校
2 . 如果存在常数a,使得数列{an}满足:若x是数列{an}中的一项,则a-x也是数列{an}中的一项,称数列{an}为“兑换数列”,常数a是它的“兑换系数”.
(1)若数列:2,3,6,m(m>6)是“兑换系数”为a的“兑换数列”,求m和a的值;
(2)已知有穷等差数列{bn}的项数是n0(n0≥3),所有项之和是B,求证:数列{bn}是“兑换数列”,并用n0和B表示它的“兑换系数”;
(3)对于一个不少于3项,且各项皆为正整数的递增数列{cn},是否有可能它既是等比数列,又是“兑换数列”?给出你的结论,并说明理由.
(1)若数列:2,3,6,m(m>6)是“兑换系数”为a的“兑换数列”,求m和a的值;
(2)已知有穷等差数列{bn}的项数是n0(n0≥3),所有项之和是B,求证:数列{bn}是“兑换数列”,并用n0和B表示它的“兑换系数”;
(3)对于一个不少于3项,且各项皆为正整数的递增数列{cn},是否有可能它既是等比数列,又是“兑换数列”?给出你的结论,并说明理由.
您最近一年使用:0次
2019-06-25更新
|
161次组卷
|
3卷引用:上海市七宝中学2017-2018学年高三上学期期中数学试题
名校
3 . 已知数列
的通项公式为
.
(1)若
成等比数列,求
的值;
(2)是否存在
使得
成等差数列,若存在,求出常数
的值;若不存在,请说明理由;
(3)求证:数列中的任意一项
总可以表示成数列中的其他两项的积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2bb567fd780a70753de8c467c9212524.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d846e3aad28af4bb52860a3592ebb4d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
(2)是否存在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e98fc3d52e6e66edee7bb2cefc0cd4e1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a294a4d7e647e4a56c8a510252a5bed7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
(3)求证:数列中的任意一项
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
您最近一年使用:0次
4 . 在等比数列
中,
,
,公比
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f3cb8d72bb2e281b943b3b430138ef7.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ef2aec453cfd42764dc743d3683c891.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5bb6489dadb98d4681cf8c44f8dae4c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b6306384fda0df72c6d027d7447c3cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f3cb8d72bb2e281b943b3b430138ef7.png)
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2019-06-14更新
|
512次组卷
|
3卷引用:上海市莘庄中学2023-2024学年高二上学期10月月考数学试题
5 . 若数列
对任意
满足
,下面给出关于数列
的四个命题:①
可以是等差数列,②
可以是等比数列;③
可以既是等差又是等比数列;④
可以既不是等差又不是等比数列;则上述命题中,正确的个数为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a018e73913627508461e913f50220df4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c948068db6f498c5d1b87a0b1940807.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/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
A.1个 | B.2个 | C.3个 | D.4个 |
您最近一年使用:0次
2019-06-14更新
|
916次组卷
|
7卷引用:上海市七宝中学2017-2018学年高一下学期期末数学试题
名校
6 . 在等比数列
中,
,
的值为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3a0925e087b51c4c0a936f962093444.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ca5fd68906de116c2cabdba74e843b5.png)
您最近一年使用:0次
2019-06-12更新
|
498次组卷
|
2卷引用:上海市七宝中学2017-2018学年高一下学期期末数学试题
名校
7 . (1)集合
,
或
,对于任意
,定义
,对任意
,定义
,记
为集合
的元素个数,求
的值;
(2)在等差数列
和等比数列
中,
,
,是否存在正整数
,使得数列
的所有项都在数列
中,若存在,求出所有的
,若不存在,说明理由;
(3)已知当
时,有
,根据此信息,若对任意
,都有
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5bbb0e2e358e148aabd5c90d955c2483.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/efe0717faf1091cbffa1918453ebf329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/659ce142c5578c660dcadacb81b8d7c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3591abc88bdadaf5fee459f4620fbd47.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4168581b97246126a4926b0754f9537d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/caff637054d4865a13f360769b486cd3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d38124e608260d696fd59cd749c3ae1c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f255d0395fba51ca2d44293cca42e0a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d7f2c72ab559a0615db4c51327b78d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac7ccc0ec88c57f4ef86ac260609d883.png)
(2)在等差数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fce83115a50f99e08e9a2db7267aeed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c5a7a17a394e868e0acd1803a9ab795.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fe8b3668a8c01835ce26100945097e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fce83115a50f99e08e9a2db7267aeed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
(3)已知当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed5497ac78def4590800f2a778d5ce9c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7ac4aec23f3f08397272da4e700fb77.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed5497ac78def4590800f2a778d5ce9c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9636c9d910d226e5685c34015da2071.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e35eeaabd951fb09b2926807da3685b.png)
您最近一年使用:0次
2020-01-16更新
|
609次组卷
|
2卷引用:上海市七宝中学2016-2017学年高二下学期期末数学试题
名校
8 . 在等比数列
中,前
项和
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/380bbacf854e30e2e747fc286d2b9997.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/e655b9f98308d9b07289657c59d0dda0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/380bbacf854e30e2e747fc286d2b9997.png)
您最近一年使用:0次
2020-01-13更新
|
272次组卷
|
6卷引用:上海市七宝中学2018-2019学年高二上学期9月摸底数学试题
名校
9 . 已知数列
满足:对任意的
均有
,其中
为不等于0与1的常数,若
,
,则满足条件的
所有可能值的和为_______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36b98ef143f8159f3a7dafa1fd2f2370.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ec295b3214120599a9c069a43ff301a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ecad7dae7d34020ca3f767fc97ed3c43.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4ad7a0ba689863d59d9b3221f4f6610.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
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2020-01-07更新
|
310次组卷
|
2卷引用:上海市闵行区七宝中学2016-2017学年高三下学期开学考试数学试题
10 . 已知数列
,
,
,则
=______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80c0062e5a519fd16ebe52ff2ba086b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f4e92d98960c31576768790fdd9c0e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36b98ef143f8159f3a7dafa1fd2f2370.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/980b58d5b67d26bd2a392d6dd07ed666.png)
您最近一年使用:0次