名校
解题方法
1 . 如图,在直角坐标系
中,圆
:
与
轴负半轴交于点
,过点
的直线
,
分别与圆
交于
,
两点,设直线
、
的斜率分别为
、
.
![](https://img.xkw.com/dksih/QBM/2020/11/5/2586652209078272/2587853242482688/STEM/93cadeda-1b59-493e-9c84-4b03fb3ce1a7.png?resizew=220)
(1)若
,
,求
的面积;
(2)若
,求证:直线
过定点.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee31829d0d4d5f779a957d7df8058ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a5f5d967ad135991b6075ee45df55643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f50b3ae183997b707d16eb4e7f6712fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f50b3ae183997b707d16eb4e7f6712fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6defc43285a40f7ccb74c1cc04265eba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/423b7ae39db552e60ee8b1d27312306f.png)
![](https://img.xkw.com/dksih/QBM/2020/11/5/2586652209078272/2587853242482688/STEM/93cadeda-1b59-493e-9c84-4b03fb3ce1a7.png?resizew=220)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd16710e91b25f9850efacebd299c9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8ff4f8895f1bc0d70524364a0a735f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98013a5042685a1db94249e70c62c09a.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d0b20880f4f6120dca1efdec01cbd7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
您最近一年使用:0次
2020-11-07更新
|
297次组卷
|
2卷引用:江西省赣州市南康中学2020-2021学年高二上学期第二次大考数学(理)试题
名校
2 . 1611年,约翰内斯·开普勒提出了“没有任何装球方式的密度比面心立方与六方最密堆积要高”的猜想.简单地说,开普勒猜想就是对空间中如何堆积最密圆球的解答.2017年,由匹兹堡大学数学系教授托马斯·黑尔斯(Thomas Hales)带领的团队发表了关于开普勒猜想证明的论文,给这个超过三百年的历史难题提交了一份正式的答案.现有大小形状都相同的若干排球,按照下面图片中的方式摆放(底层形状为等边三角形,每边4个球,共4层),这些排球共__________ 个,最上面球的球顶距离地面的高度约为__________
(排球的直径约为
)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9efa9fbcfb9595e2f031aa691db4564b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d2eb8ac733873fb3e728399ac856f16.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/8/0c87873d-c7f2-4a40-aad6-fc2f10261701.png?resizew=133)
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2020-04-24更新
|
427次组卷
|
2卷引用:2020届甘肃省第一次高考诊断考试理科数学试题
名校
3 . 组合恒等式
,可以利用“算两次”的方法来证明:分别求
和
的展开式中
的系数.前者
的展开式中
的系数为
;后者
的展开式
中
的系数为
.因为
,则两个展开式中
的系数也相等,即
.请用“算两次”的方法化简下列式子:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89a5da8ca5f9f82b603a776cf7c047e2.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0a27dc7f3952c6b6a11376205e7026f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5da7bfad011650578d8d6932e040c108.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abcb23d99fdb65d7a60cae3aa4364a89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbc1fb81fa5b128500c08c9593d6a89e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5da7bfad011650578d8d6932e040c108.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbc1fb81fa5b128500c08c9593d6a89e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e8e1995ad54cd7c9ddfd43dab19b1ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abcb23d99fdb65d7a60cae3aa4364a89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f2832587e638ed851652d60ca716b8d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbc1fb81fa5b128500c08c9593d6a89e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/445a256f8985606f98f015d84b36b691.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/663c307dad10414d54127f8ebef28a75.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbc1fb81fa5b128500c08c9593d6a89e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0a27dc7f3952c6b6a11376205e7026f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89a5da8ca5f9f82b603a776cf7c047e2.png)
您最近一年使用:0次
2019-07-01更新
|
1178次组卷
|
2卷引用:江西省南昌市八一中学、洪都中学、麻丘高中等七校2018-2019学年高二下学期期末考试数学(理)试题
4 . 设向量
,
,其中
,
,
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
,由不等式
恒成立,可以证明柯西不等式
(当且仅当
,即
时等号成立).已知
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
,若
恒成立,利用柯西不等式可求得实数
的取值范围为________________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a0fb4d6477160c8964034ca02de3b56.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/557ca73405c6884f688c46ee8daad7ef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/160daec0ad9ccc242f3e259eb4d61ef6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51ac29b9c6ad0825a3f0e8489c10a4d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f0c314051906863d6c9502fb3faf585.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1bf91d09e73dec24c2f764d421ad64ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd68c14adb3cf12d8f77aec55a053284.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b03f2fbdd3eee86346e04ddee66b2f8d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/881b614a0277c307159db0f8178fc39d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
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