名校
解题方法
1 . 数列
满足
则称数列
为下凸数列.
(1)证明:任意一个正项等比数列均为下凸数列;
(2)设
,其中
,
分别是公比为
,
的两个正项等比数列,且
,证明:
是下凸数列且不是等比数列;
(3)若正项下凸数列的前
项和为
,且
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a0bee75d4d83c0b76421fd87113e4dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(1)证明:任意一个正项等比数列均为下凸数列;
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f67fc95a626251da11649acb5e1706f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b783cf91e34e692ce8e171f0965cb53f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c340d7d093dd4a275ffea4b87cd26827.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6268630d5e5288048d32f4aa5c8bc02d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c171ff5c2728e7cf00a88f88de14f308.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3755d7aa870e2f199d6c12264fc9be86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
(3)若正项下凸数列的前
![](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/0002f427eded1721f43d60dd0fd3ffe0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd419dc0a6580ab97777b2cb8fd7cded.png)
您最近一年使用:0次
2024-06-12更新
|
1139次组卷
|
5卷引用:2024届湖北省高三普通高中5月联合质量测评数学试卷
名校
解题方法
2 . 在无穷数列
中,若对任意的
,都存在
,使得
,则称
为m阶等差数列.在正项无穷数列
中,若对任意的
,都存在
,使得
,则称
为m阶等比数列.
(1)若数列
为1阶等比数列,
,
,求
的通项公式及前n项的和;
(2)若数列
为m阶等差数列,求证:
为m阶等比数列;
(3)若数列
既是m阶等差数列,又是
阶等差数列,证明:
是等比数列.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/930bc56406e69b785b37a83d48e36724.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bd2c3166d0bfd9e64bdc85081445e95.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f57ae28a9ca230ff60fff6406b06ba96.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/930bc56406e69b785b37a83d48e36724.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bd2c3166d0bfd9e64bdc85081445e95.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc8483c0e1d0daabfa8130baa9737eea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(1)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/674f03ad5f8c00ce301ecb176fb23277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e25fe433dbc540279bc50cf65c7f5fc4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ec50a8616d7700de94ee53c2b5dac43.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
(3)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ec50a8616d7700de94ee53c2b5dac43.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0623207595425920f16e76a7f8f268b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
您最近一年使用:0次
2024-05-31更新
|
363次组卷
|
3卷引用:贵州省毕节市2024届高三第三次诊断性考试数学试题
3 . 设
,
,
(1)证明:
;
(2)若存在直线
,其与曲线
和
共有3个不同交点
,
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/830c98ceab2c157eac58caaf717b6de4.png)
,求证:
,
,
成等比数列.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ff6838d84b68c6f0d3b93b196d9b08d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e9f049a5f960728c60a909821b2404b.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2745c151102f2f028ba4976369f859be.png)
(2)若存在直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4ff39dd1dfc9caf911ad0d11ba21d66.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a28b3589f39573e9cc7d6684a033f24.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fdd5552324550304765749352051d850.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db8828dad2747f16ae4efee1ac0344a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/328071ace61d03885e3bc122b2713ffe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/830c98ceab2c157eac58caaf717b6de4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4c06ceee2b1e227de025476eee95672.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c814128ea2139e33db94ea590e7c2223.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aec19b68e3add9d5bfcc6269a1855b87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/291c25fc6a69d6d0ccfb8d839b9b4462.png)
您最近一年使用:0次
4 . 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)
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5 . 如图,矩形
中,
,
.
、
、
、
分别是矩形四条边的中点,设
,
.
与
的交点
在椭圆
:
上;
(2)已知
为过椭圆
的右焦点
的弦,直线
与椭圆
的另一交点为
,若
,试判断
、
、
是否成等比数列,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08e39fda3cda5ddc03b085413f2030aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f17edac849a0691e52146021e05d83e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97c01fdc7bc471af0b264a04aef0823e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd3b9e816b14051f785aa5aae72b8eed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43a71fc9c0068109dad1382354570665.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c97826ac106f5f52aba70a490617df5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71b6b1972e45108889781ed1dd7ddcd2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba28c45f78fb7643ec9781a800271cc5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c7ebdc16bd34f6daddd1a988ab2ac68.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf3834d7ec7531f3c3c0ce9b286f7a49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c82e7d9f4f7ace849e09e9adcb786b7f.png)
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf3834d7ec7531f3c3c0ce9b286f7a49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4cfef623a9534b5708df5f95f1760a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf3834d7ec7531f3c3c0ce9b286f7a49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c55885a1d570815af33936d4d3e1d50.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3d87446c9ef0230285d9b08127fce5c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb40dae2b0f4048d3fabff25e6cbe443.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/40d76468043c2c7b5a8050a82471c161.png)
您最近一年使用:0次
名校
6 . 已知常数
,设
,
(1)若
,求函数
在
处的切线方程;
(2)是否存在
,且
依次成等比数列,使得
、
、
依次成等差数列?请说明理由.
(3)求证:当
时,对任意
,
,都有
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcd9218a657b17654c5d757a6f7dee9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7df71f8b32945f3915dd2a0b72593bed.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf0086b054ef120408acac806a1b1318.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/942c2141d01bde6b48210c56a17fc75e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29343388ca8b33dc98325e65382b38a0.png)
(2)是否存在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1757236a5ef1fc70a18f31d6d2438b18.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05b8ec9d4206ea66a02de5c4a1e1e911.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc9769116ec47353514e6b7fb7b17216.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/542893790445d6d888d9ff91fd215c9c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb1e5fb2d54a62f243bd5936a3f60386.png)
(3)求证:当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a878fd5a7104a7f42770a19097d56457.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42fd7af568e3d9f444beb0ff41426477.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26d8dafc71b106f39f4e15442220897b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a620b284ae80049376c7a7c9afab1f62.png)
您最近一年使用:0次
7 . 已知
为等差数列,公差
,且
、
、
成等比数列.
(1)求数列
的通项公式;
(2)记
,数列
的前
项和为
,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5c1344592c925b273f2cb9b9e47ebbb.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/f65fc200f10b97588a0c9896277c9c64.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d005409790b3192705a181b2c8e7dfed.png)
![](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/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc1f5d407c0e99344ed5f0f5926c5d22.png)
您最近一年使用:0次
2024-03-08更新
|
2488次组卷
|
6卷引用:四川省大数据学考联盟2024届高三第一次质量检测数学(文科)试题
8 . 已知双曲线
,动直线
与
轴交于点
,且与
交于
两点,
是
的等比中项,
.
(1)若
两点位于
轴的同侧,求
取最小值时
的周长;
(2)若
,且
两点位于
轴的异侧,证明:
为等腰三角形.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/117b2c5ee2d21be3b6d9fe8c08d8f7ad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccf506477b8a7a14dde4131eb52f22a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91edc7e2d4811f5ea6c01284cf00393a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39acab3cfb59bfc9591371721ab01d93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c417d3cc5e4022c2acdec5e441eb4c43.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89d0c7793dec7840e3f9e6a03cd6baf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9bf039c46a25e331446c6ee1e9af3c82.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39acab3cfb59bfc9591371721ab01d93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ac451db3443cabb204f96c31fd4a02e.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a2a51944c720568f35d443589dfc1aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39acab3cfb59bfc9591371721ab01d93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ac451db3443cabb204f96c31fd4a02e.png)
您最近一年使用:0次
解题方法
9 . 混沌现象普遍存在于自然界和数学模型中,比如天气预测、种群数量变化和天体运动等等,其中一维线段上的抛物线映射是混沌动力学中最基础应用最广泛的模型之一,假设在一个混沌系统中,用
来表示系统在第
个时刻的状态值,且该系统下一时刻的状态
满足
,
,其中
.
(1)当
时,若满足对
,有
,求
的通项公式;
(2)证明:当
时,
中不存在连续的三项构成等比数列;
(3)若
,
,记
,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3282e5fde4ae53fcb1bb072a685304c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034983375860d2b404f6fbd7d40a44b1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3002f56900c2924bfd79fc3865b0a02e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc85a01f2a5b003d545aabd58658f430.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4d5b159da139b50cde0d087f462aa4d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0cb047913c41b42b47ac00bf91f2e45.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e65397f11ea8af736f38debadf420c4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f8365233f341451598eb50525a1557a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd3d565c588f31510c613f32122778ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e976c0663fa749ca749f99842d21ca03.png)
(2)证明:当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b550ee821ee1838384835e81fc34b67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e976c0663fa749ca749f99842d21ca03.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/195fc747e2fc50cb6df2c844d51e4d80.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b550ee821ee1838384835e81fc34b67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3fbbb97adee9c7cb6af553e1c8e2b047.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/69c7636532d8414f52061bba28a1b9a3.png)
您最近一年使用:0次
解题方法
10 . 已知数列
的首项为3,且满足
.
(1)求证:
是等比数列;
(2)求数列
的通项公式,并判断数列
是否是等比数列.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7bab423942f5e4d37c150ccfaf9f055.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7695d7b6905ff9d4cd9b063028cc092.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
您最近一年使用:0次
2023-12-04更新
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1876次组卷
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10卷引用:四川省成都市郫都区2024届高三上学期阶段检测(二)文科数学试题
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