1 . 大衍数列,来源于中国古代著作《乾坤普》中对易传“大衍之数五十”的推论.其前
项为:
、
、
、
、
、
、
、
、
、
,通项公式为
,若把这个数列
排成下侧形状,并记
表示第
行中从左向右第
个数,则
的值为( )
![](https://img.xkw.com/dksih/QBM/2022/5/24/2986258253430784/2987905284407296/STEM/261aec48-dc18-48af-9484-70b13cd56b48.png?resizew=156)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d07ae0b4264da6a8812454ffd2f20d94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c95b6be4554f03bf496092f1acdfbb89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8860d9787671b53b1ab68b3d526f5ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd3304e23f3b0f9569c4140ca89b6498.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8da45c443af7994a26ffa9d8894e7262.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b837fd9c52f60bfb3b6852733abc790.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49e60fbe6820130fb20abc555a94b5ea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/814397354c2ae1cb08e0271305970811.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b72ac611ae66b86761e080761d9aabc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e6f1af4b44b2e97e8f319bab4ae9010.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15b5e75a9c9d19bae25c92dc48e31588.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a66c5f00b5b38a2d052354b5611970e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8319ceb31be84a58c6f13a694a86f11d.png)
![](https://img.xkw.com/dksih/QBM/2022/5/24/2986258253430784/2987905284407296/STEM/261aec48-dc18-48af-9484-70b13cd56b48.png?resizew=156)
A.![]() | B.![]() |
C.![]() | D.![]() |
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解题方法
2 . 在
中,
分别为三个内角
的对边,若
.
(1)求角
;
(2)若
,
,D为
的中点,求
的长度.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88f2599ca8b6b683e57a82699c8b1ebb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce7af7c5df749c6fa9bbe87faa72c66d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da714623a6024938c82ca5f5c7940271.png)
(1)求角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44bd8ca938b929fe0dea5a904fe34aee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a47ec05f5c5425d47418074254dbd4e2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
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2022-05-26更新
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4卷引用:新疆克拉玛依市2022届高三下学期第三次模拟检测数学(文)试题
新疆克拉玛依市2022届高三下学期第三次模拟检测数学(文)试题新疆克拉玛依市2022届高三下学期第三次模拟检测数学(理)试题(已下线)专题14 解三角形图形类问题-2(已下线)微专题09 解三角形图形类问题(1)-【微专题】2022-2023学年高一数学常考点微专题提分精练(人教A版2019必修第二册)
3 . 南宋数学家杨辉在《详解九章算法》和《算法通变本末》中,提出了一些新的垛积公式,所讨论的高阶等差数列与一般的等差数列不同,前后两项之差并不相等,但是逐项差数之差或者高次成等差数列.如数列1,3,6,10,前后两项之差组成新数列2,3,4,新数列2,3,4为等差数列,这样的数列称为二阶等差数列.现有二阶等差数列,其前7项分别为2,3,5,8,12,17,23,则该数列的第31项为( )
A.![]() | B.![]() |
C.![]() | D.![]() |
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4 . 等比数列
满足
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61890afaac9d3df5c2dbd6719718e2ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dbd9ff686703cad03aa383e5fec21.png)
A.1 | B.![]() | C.![]() | D.![]() |
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2022-05-24更新
|
692次组卷
|
2卷引用:新疆乌鲁木齐地区2022届高三下学期第三次质量监测数学(理)试题(问卷)
解题方法
5 . 已知
为单调递减的等差数列
的前n项和,若数列
前n项和
,则下列结论中正确的有______ .(填写序号)
①
;②
;③
;④
.
![](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/ba57c83d526ac308d1461e80fcca9f36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c9854d8e0cdc18b0acc44a5786dbff7.png)
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58365ff21052f2f978c11844b002b933.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43c179caa067a39909537e4454e69943.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/769e691cda5afd33e75ecd2ef21d3e07.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b6df0c55b4ce6c687a05d5dadea34ab.png)
您最近一年使用:0次
6 . 在
中,D为
上一点,
.
(1)求
;
(2)求
的面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f3388138948b4237db4c952975c55b8.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7ac5396c5ea442e0364b50c1db3d2da.png)
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2022-05-22更新
|
367次组卷
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2卷引用:新疆乌鲁木齐地区2022届高三下学期第三次质量监测数学(理)试题(问卷)
7 . 设等差数列
的前n项和为
,若
,
,则
( )
![](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/2693734765399876e9e93cdb110231c4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/28d84ee688592caf22e84910db79e7d0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc4e70b360f988fdbd92300ab22c4613.png)
A.75 | B.78 | C.81 | D.84 |
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解题方法
8 . 在△ABC中,角A,B,C的对边分别为a,b,c,已知
,
,
.
![](https://img.xkw.com/dksih/QBM/2022/5/14/2979257997246464/2979394794127360/STEM/dcb7a4f3-63e4-459f-8889-420e5ad27433.png?resizew=136)
(1)求
的值;
(2)在边BC上取一点D,使得
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e65397f11ea8af736f38debadf420c4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6de1d395e6c48c0676a1488a299479d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b1dd07c0571772e96d318f974724810.png)
![](https://img.xkw.com/dksih/QBM/2022/5/14/2979257997246464/2979394794127360/STEM/dcb7a4f3-63e4-459f-8889-420e5ad27433.png?resizew=136)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c32e2f2d7147cf1699fbfdef9cf4af74.png)
(2)在边BC上取一点D,使得
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b5656661f1d7fd5b403d1dd39d1adfd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/168bcd54c4f609a9562c2d7b4715aa4b.png)
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2卷引用:新疆维吾尔自治区2022届高三年级第三诊断性测试数学(文)试题(问卷)
名校
9 . 数列
满足
,且
,则数列
的前12项的和为__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ef9a7b9e3ae72e83ccb88f184581e08.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
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2022-05-14更新
|
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2卷引用:新疆维吾尔自治区2022届高三年级第三诊断性测试数学(文)试题(问卷)
解题方法
10 . 设
为数列
的前n项和,若
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc4e70b360f988fdbd92300ab22c4613.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/fe15115cadae7d8a14b4738716457cd6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc4e70b360f988fdbd92300ab22c4613.png)
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