已知数列
的前n项和为
,且
,
.
(1)求数列
的通项公式;
(2)在
与
之间插入n个数,使这
个数组成一个公差为
的等差数列,在数列
中是否存在3项
,
,
(其中
成等差数列)成等比数列?若存在,求出这样的3项,若不存在,请说明理由.
![](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/beb08c935c5a6dae2b2e53cfa8eac740.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/039e4fe671d61e59b96ee525c9df43e8.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/090426eb29836bc30c006b3739c08057.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3468a665ac713ab7b400c672f19650a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82e260b088f071983f254ce8f5163fcd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b783cf91e34e692ce8e171f0965cb53f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee8598379ec01edc16c72c1d3fa3ce81.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8904e7018ec79c8b0efdcb3ba67cb7cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2554efe1860dc6c769c34d8cfa6de3e4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7955013519718c9ac993531062495e95.png)
更新时间:2024-02-29 23:41:41
|
相似题推荐
解答题-问答题
|
较难
(0.4)
名校
解题方法
【推荐1】已知双曲线C;
经过点
,右焦点为
,且
成等差数列.
(1)求C的方程;
(2)过F的直线与C的右支交于P,Q两点(P在Q的上方),PQ的中点为M,M在直线l:
上的射影为N,O为坐标原点,设△POQ的面积为S,直线PN,QN的斜率分别为
,
,证明:
是定值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a5ec7fa23be9cbe9a50607ea6bc8a4ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f39eb7186f7252fff8782f1ec117f839.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24550b13dbecf7d86c7054250e987274.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2645495fd5e1f0fb701b7d34d7fb660.png)
(1)求C的方程;
(2)过F的直线与C的右支交于P,Q两点(P在Q的上方),PQ的中点为M,M在直线l:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/707ea658f3a9359f5740d5aab48f7948.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6defc43285a40f7ccb74c1cc04265eba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/423b7ae39db552e60ee8b1d27312306f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e1bce754a5eeb5e03969586dab2554f.png)
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【推荐2】已知数列
满足
,设该数列的前n项和为
,且
成等差数列.
(1)用
表示
;
(2)求数列
的通项公式.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/381576e698a46df8c497e6b5f8346ddc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eaec34fbe77931712f4fbf32f6134301.png)
(1)用
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebadf2b3ec3dc92cd902eff76085ad46.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
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解答题-证明题
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(0.4)
名校
【推荐1】已知数列
是公差
的等差数列,记
为其前n项和
(1)若
,
,
依次成等比数列,求其公比q;
(2)若
,
,求证:点
都在同一条直线上;
(3)若
,
,
,是否存在一个半径最小的圆,使得对任意
,点
都在这个圆内或圆周上,如果存在,写出这个圆的方程;如果不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/812be9806122241c476ba1db516c4823.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c1ccc6c74b8754e9bcbb3f39a11b6f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5da4cd81500bdb43118150dbdb1541e6.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/151edf1bc8623f18caf42b883fbb3c12.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf83e20035c3afd6d26ebfd53d768a70.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ec5092048ae59b74623c4be1048c8c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32ce73a29613e7b5170d948d000873c8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f093c61867ee4ce75f951d46b9b123.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15520cf5be7c2685975aac51bc99ac4f.png)
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【推荐2】已知A,B分别为椭圆
的上下顶点,P为直线
上的动点,且P不在椭圆上,
与椭圆E的另一交点为C,
与椭圆E的另一交点为D,(C,D均不与椭圆E上下顶点重合).
(1)证明:直线
过定点;
(2)设(1)问中定点为Q,过点C,D分别作直线
的垂线,垂足分别为M,N,记
,
,
的面积分别为
,
,
,试问:是否存在常数t,使得
,
,
总为等比数列?若存在,求出t的值;若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4574be1104de2f44eca29d8787fff20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/020d714d62aacf77f1f89f575931659f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
(1)证明:直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
(2)设(1)问中定点为Q,过点C,D分别作直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/020d714d62aacf77f1f89f575931659f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51496e5f2d2f91c5c4aade9bc504ecfb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed283a253b61df01f2a1cdc0cd8003f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/589554d1c4a022cf782658a7856f8f0a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e097c8d4c948de063796bd19f85b3a9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e0bd63f55069a3bc870915010b39225.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6899bf9cadae2ccdb14cbc87d4f280ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e097c8d4c948de063796bd19f85b3a9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3d0e5912f14c7c91801387a2e93684b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6899bf9cadae2ccdb14cbc87d4f280ee.png)
您最近一年使用:0次
【推荐1】已知数列![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
的各项为正,且
,
是公比为
的等比数列.再从:
①数列
的前
项和
满足
:
②数列
是公差不为0的等差数列,且
,
,
,
,成等比数列.
这两个条件中任选一个,解答下列问题.
(1)求数列
,
的通项公式;
(2)令
,设
的前
项和为
若
对
恒成立,求实数
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/716d6be9fcea44d5327c3e84184cd59e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1eac760b66505fd1c5f53aed6f76a09a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/716d6be9fcea44d5327c3e84184cd59e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dac452fbb5ef6dd653e7fbbef639484.png)
①数列
![](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/59c29e8bfe54e4444a6135e67801f7e6.png)
②数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8713c0a55c04fe0fc20259095d63c631.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daf464629fa321a6ff7401ab79f07083.png)
这两个条件中任选一个,解答下列问题.
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/716d6be9fcea44d5327c3e84184cd59e.png)
(2)令
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c10431ad1574c5f8cd97211d05978af1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6bcfed89f8a34706d44b649b4fe7a1d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0492860bb97f265792fcc80fd5697dad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
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解答题-问答题
|
较难
(0.4)
名校
解题方法
【推荐2】记数列
的前n项和为
,其中所有奇数项之和为
,所有偶数项之和为![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fdd3e46b2b2a97f5296aece98ba9279e.png)
若
是等差数列,项数n为偶数,首项
,公差
,且
,求
;
若数列
的首项
,满足
,其中实常数
,且
,请写出满足上述条件常数t的两个不同的值和它们所对应的数列.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe229b24e2d56ff6b491725ceae4ff2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b708c8dcb2d66eb2ce0b3718a9cd924a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4866d1c01cd46de5d1d9448e4104e15e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fdd3e46b2b2a97f5296aece98ba9279e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4141b26d2c32655003494a91ad6331b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe229b24e2d56ff6b491725ceae4ff2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/381576e698a46df8c497e6b5f8346ddc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c901eee27dbbcbe46e52c9f72c201d61.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/75f179aeceb1c525c8f7f27d61c9351c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b708c8dcb2d66eb2ce0b3718a9cd924a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65863c1abad833b79c303bfca24f535c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe229b24e2d56ff6b491725ceae4ff2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/381576e698a46df8c497e6b5f8346ddc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/400c3af7900b809e38a67c906ed23d83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43f45c342373d9253df5c132a2e9b87b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/371a7f8799f3bc81797bdedf4a282dad.png)
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解答题-证明题
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较难
(0.4)
解题方法
【推荐1】已知数列
的各项为正数,其前
项和为
满足
,设
.
(1)求证:数列
是等差数列,并求
的通项公式;
(2)设数列
的前
项和为
,求
的最大值.
(3)设数列
的通项公式为
,问: 是否存在正整数t,使得
成等差数列?若存在,求出t和m的值;若不存在,请说明理由.
![](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/71e3fada69fbdbf095b43d1367df81bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c9f2a118078a2b40285bbfa38d71ff7a.png)
(1)求证:数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)设数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
(3)设数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8bb3d881b0b0c328f4c2cfa55e54a25.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f401b2388e91b87ddc12aacf25f1b342.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5659565f5638ab4609a7edc252370039.png)
您最近一年使用:0次
【推荐2】已知数列
,
,
是数列
的前n项和,已知对于任意
,都有
,数列
是等差数列,
,且
,
,
成等比数列.
(1)求数列
和
的通项公式;
(2)记
,
(i)求数列
的前n项和
;
(ii)求
.
![](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/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1505d56f0b35fe7f2de1fe1888036e4c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6236cfb43def832ee82170a3957976ae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52e228119072e6686e99ee479537dedb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/161e6bfee24c80834e0f013f5c6da3ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72c556533e5d1a21895c1dca698d8dc3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e82fce48347b206a27cf7219e43ffc0.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0bc8d0177d757a35fd1826cff55ccc14.png)
(i)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
(ii)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/088933c82db929cef6093c55fa9618f5.png)
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