解题方法
1 . 已知等比数列
的前
项和为
,
,且
,
,
成等差数列.
(1)求数列
的通项公式;
(2)已知
,求数列
的前
项和
.
![](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/85f7519e1b1dd927bc634eedafc88820.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4b32aee86109b777671cd62868db3b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e86e2e42b4aa93db9241103e7f61766c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daf464629fa321a6ff7401ab79f07083.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4afc0af2902e226cd3cb15a4b3343c01.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/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
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2 . 抛物线
的焦点到直线
的距离等于( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/745de5ef1fd897d16e37464172d5e8c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b979396a703fb14715ba39232f5786a.png)
A.1 | B.![]() | C.![]() | D.4 |
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解题方法
3 . 在直角坐标系
中,已知椭圆
的左右焦点分别为
,
,离心率是
,点P为椭圆短轴的一个端点,
的面积是
.
(1)求椭圆的方程;
(2)若动直线
与椭圆
交于
两点,且恒有
,是否存在一个以原点
为圆心的定圆,使得动直线
始终与定圆相切?若存在,求出圆的方程,若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee31829d0d4d5f779a957d7df8058ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7e5578ca83f5bd5c285994061b9c015.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5076289823db419f94e9c0c8f4aafd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5076289823db419f94e9c0c8f4aafd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/860884c0017c8bceb5b0edff796c144f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33d776753746914c2410a3946c357f35.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7ffe8515ff6183c1c7775dc6f94bdb8.png)
(1)求椭圆的方程;
(2)若动直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc11e7549cfce9220e70250ac943e457.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
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解题方法
4 . 如图,在棱长为2的正方体
中,
分别为
,
的中点,则( )
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/23/b7475a0e-f19a-4ad2-9f26-74ff652978af.png?resizew=170)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad056c25c0fdcbcc765eb5cbc6093f2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e26d9636ad77369535852c6e4493446a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7f6f93171329d508d491143b9d71f7b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/23/b7475a0e-f19a-4ad2-9f26-74ff652978af.png?resizew=170)
A.![]() |
B.![]() ![]() |
C.异面直线![]() ![]() ![]() |
D.平面![]() ![]() ![]() |
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5 . 如图,
平面
,
,
,
,
,
,点E,F,M分别为
,
,
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/23/e0054b2a-4e49-456d-ac39-ce2b4b0c735b.png?resizew=143)
(1)求证:
平面
;
(2)求平面
与平面
的夹角的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1b49f64e0065edad868b25e9fcada3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cdb2dd10731b99c0f4f89ee957f8a239.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10df84d553a8826a7ce9bff4bf0d95b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6902045cae4fa4d2fdcd77bc3784df55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d892c28f02973dfefd26a22b2b7f923f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f221b797bf8f7f7edc3255a770d0f5f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb6ede9761b5b90f8dc137708e1ee90f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/23/e0054b2a-4e49-456d-ac39-ce2b4b0c735b.png?resizew=143)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57f9d682e5d3cc8573574d8d11636758.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d9a5a17b1dcdb86b84c3712527282d7e.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe83f1ae7e5f05d8bed6bf6f42db0e7d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d9a5a17b1dcdb86b84c3712527282d7e.png)
您最近一年使用:0次
6 . 已知向量
若
与
、
共面,则实数
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a66de7503a09fb859b15c384fcf3a25f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4478fcaef66e8a6a96925ce12d0f8e8f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64c5562bd4d1b54424330cb6329cd79d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b45ba716f03748c19b7ce2f99af536ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5085e3cdef9ea6c564e079f745d6fdb.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
解题方法
7 . 数列
的前
项和为
,已知
,则下列说法正确的是( )
![](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/98330ed390da74f2ebbe52d1c4af3183.png)
A.![]() | B.数列![]() |
C.当![]() ![]() | D.当![]() ![]() |
您最近一年使用:0次
解题方法
8 . 已知直线
:
和圆
:
.
(1)求圆C的圆心坐标和半径;
(2)求经过圆
的圆心且与直线
垂直的直线方程.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2b905d12adb1d83dd79b0b6512a32ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/705d6d0a046281db9a588d76b4fc2199.png)
(1)求圆C的圆心坐标和半径;
(2)求经过圆
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
您最近一年使用:0次
解题方法
9 . 35是等差数列3,5,7,9,
的( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daa5e9bd516f6282483b92cfe6074623.png)
A.第16项 | B.第17项 | C.第18项 | D.第19项 |
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10 . 已知抛物线的准线方程为
,则抛物线的标准方程为_________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c98a7f3a8bf384b1dfc1d34aebd46d2.png)
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