1 . 已知椭圆
的离心率
,且点
在椭圆E上,直线
与椭圆E交于不同的两点A,B.
(2)设直线OA,OB的斜率分别为
,证明:
;
(3)设直线l与两坐标轴的交点分别为P,Q,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7e5578ca83f5bd5c285994061b9c015.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50bbe873760a74d9aedaafc98fe7e83c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/451ee8353864dfdb87e3a44eb505f83c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e02a893620592d2ab3e3c0bff6529f0.png)
(2)设直线OA,OB的斜率分别为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90963760acac7bfad3ae03088c6c80b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a778e57014d81a57b823ef7761aec5bd.png)
(3)设直线l与两坐标轴的交点分别为P,Q,证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d0b8ae5b933dd37b9311034029a0a17.png)
您最近一年使用:0次
2 . 已知点
在椭圆
上,F为右焦点,PF垂直于x轴.A,B,C,D为椭圆上四个动点,且AC,BD交于原点O.
(1)求椭圆E的方程;
(2)设
,
,满足
,判断
的值是否为定值,若是,求出此定值,并求出四边形ABCD面积的最大值,否则请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/206f399225d65980f156b19206d9bac4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a200ca2c4af794f4d1c6a5443830b5f.png)
(1)求椭圆E的方程;
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12a3efb79f35db8448f3391252ab7d4e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8df332f01628130c084fd46aaca0a4b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ee813b2123325ac177f58c698c0144c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2992389255a27bf631763317f62f3922.png)
您最近一年使用:0次
2024-04-10更新
|
204次组卷
|
3卷引用:宁夏银川市唐徕中学2024届高三下学期适应性考试数学(理)试题
名校
解题方法
3 . 已知
,
分别是椭圆
的左、右焦点,左顶点为A,则上顶点为
,且
的方程为
.
(1)求椭圆
的标准方程;
(2)若
是直线
上一点,过点
的两条不同直线分别交
于点
,
和点
,
,且
,求证:直线
的斜率与直线
的斜率之和为定值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5076289823db419f94e9c0c8f4aafd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3fb78c5f885034612c0e030b920143d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/851a5d6ec23256f9b4a9e98aa92945fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97c01fdc7bc471af0b264a04aef0823e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b470c4e195cf7a07b7a331ce4b436e03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abc6a1be030fc90af53cc09ec98768ef.png)
(1)求椭圆
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e55aa0a20848c37c1892c567b2315e04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.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/5ebca0c89a6431c34526d17eccb08594.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
您最近一年使用:0次
4 . 已知焦点在
轴上,中心在原点,离心率为
的椭圆经过点
.
(1)求椭圆
的方程;
(2)若动点
,
(不与定点
重合)均在椭圆上,且直线
与
的斜率之和为1,
为坐标原点
(ⅰ)求证:直线
经过定点;
(ⅱ)求
的面积
的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/860884c0017c8bceb5b0edff796c144f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97caea8ea20c118920d887d2ee9ac83d.png)
(1)求椭圆
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
(2)若动点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b66a5b7813e902306477f91f9f4084cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e5c62f22d7afc5627fcb86599faa8e1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
(ⅰ)求证:直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
(ⅱ)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2b83beedb3438153e6f728545fe3e03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
您最近一年使用:0次
5 . 在平面直角坐标系
中,点A,B分别在x轴,y轴上运动,且
,动点P满足
.
(1)求动点P的轨迹C的方程;
(2)设点M,N在曲线C上,O为坐标原点,设直线
,
的斜率分别为
,
,且
,试判断
的面积是否为定值?若为定值,求出该定值;若不为定值,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee31829d0d4d5f779a957d7df8058ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/529b4836786aca156de325464ea2ecd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eee4dbf8d1be07b2f95ac0d26a9262f9.png)
(1)求动点P的轨迹C的方程;
(2)设点M,N在曲线C上,O为坐标原点,设直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aaf3369e0ea90e8d5cf4b6b3c45c0fd8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88e9f7d1272b7344346b58b660aa260a.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/02324abee955451054237a932230500a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4f02028a3847c4807c2d3cf0ea7efb8.png)
您最近一年使用:0次
2024-01-14更新
|
896次组卷
|
5卷引用:宁夏银川市第二中学2024届高三第一次模拟考试数学(理)试题
宁夏银川市第二中学2024届高三第一次模拟考试数学(理)试题陕西省宝鸡市2024届高三上学期高考模拟检测(一)数学(理)试题重庆市九龙坡区重庆实验外国语学校2024届高三下学期入学测试数学试题(已下线)专题06 直线与圆、椭圆方程(分层练)(三大题型+12道精选真题)内蒙古自治区呼和浩特市剑桥中学2023-2024学年高二下学期第一次(3月)月考数学试题
2024·全国·模拟预测
6 . 已知
为坐标原点,椭圆
的上焦点
是抛物线
的焦点,过焦点
与抛物线对称轴垂直的直线交椭圆
于
两点,且
,过点
的直线
交椭圆
于
两点.
(1)求椭圆
的标准方程;
(2)若点
,记
的面积为
的面积为
,求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef404abca1f78da130a38849f58559.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5adbd62cb6779bc3b445dcbef97e3bf5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7789a500686c7a73770404ead6af0590.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c841c11140900fd14e2fda2dda42a506.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46c02f5667d9bcb19ef19750a65b1e7c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
(1)求椭圆
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97fb96d52f1ab7cd9c4e9427838bd6e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/729684f958ad60b8e905fe1e1da53c03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e177f4f96900be94ee7e1db0b4169f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e0bd63f55069a3bc870915010b39225.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b4d8e7425fe8bafd8e04fd9b8bbbe45.png)
您最近一年使用:0次
2024-01-05更新
|
1177次组卷
|
7卷引用:宁夏回族自治区银川一中2024届高三下学期第一次模拟考试数学(理)试题
宁夏回族自治区银川一中2024届高三下学期第一次模拟考试数学(理)试题(已下线)2024年普通高等学校招生全国统一考试数学文科预测卷(七)(已下线)江苏省泰州市兴化市2023-2024学年高二上学期期末数学试题广东省广州市中山大学附中2024届高三上学期第一次调研数学试题湖南省长沙市立信中学2023-2024学年高二上学期期末考试数学试题(已下线)黄金卷06(2024新题型)(已下线)专题 7 面积最值 坐标思想(高考试题一题多解)
名校
解题方法
7 . 已知椭圆
的上顶点为
,左、右焦点分别为
,
,离心率
的面积为
.
(1)求椭圆
的标准方程;
(2)直线
与椭圆
相交于点
,则直线
的斜率分别为
,
,且
,则直线
是否经过某个定点
?若是,请求出
的坐标.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7e5578ca83f5bd5c285994061b9c015.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5076289823db419f94e9c0c8f4aafd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3fb78c5f885034612c0e030b920143d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4473166ff6a7cf58484d0920919f90e4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7ffe8515ff6183c1c7775dc6f94bdb8.png)
(1)求椭圆
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
(2)直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3cefc3d799ca0b4b14e4cc3d24459a19.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6bce3d91ca23b86d8c6625f2632e437.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa154ac33703b5c836047b2143697c6d.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/1ae3ab048431fdc75f9a2eef2a762f37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
您最近一年使用:0次
2023-12-28更新
|
1541次组卷
|
6卷引用:宁夏回族自治区银川市银川一中2024届高三上学期第六次月考数学(文)试题
宁夏回族自治区银川市银川一中2024届高三上学期第六次月考数学(文)试题宁夏回族自治区银川市银川一中2024届高三上学期第六次月考数学(理)试题2024届四川省成都市成华区某校高三上学期一模数学(文)试题(已下线)模块五 专题4 期末全真模拟(能力卷2)期末终极研习室(高二人教A版)(已下线)每日一题 第23.题 存在问题 结论先行(高二)广东省中山市中山纪念中学2024届高三上学期第二次调研数学试题
名校
解题方法
8 . 已知圆
:
,点
是圆
上的动点,点
,
为
的中点,过
作
交
于
,设点
的轨迹为曲线
.
(1)求曲线
的方程;
(2)过点
的动直线
与曲线
相交于
,
两点.在平面直角坐标系
中,是否存在与点
不同的定点
,使
恒成立?若存在,求出点
的坐标;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8faf033f0e08446eae914cb8d21a863.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62d314b47d37c9f58e05ad11f3e68e27.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/907d5147cea4c9ce855074864fe54506.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3cbb57a19dff0f257735448a0261cee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ce6c0e9de83f2e64ae33609fc08459d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(1)求曲线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)过点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1b6f209d1a805437046ca6ef79dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee31829d0d4d5f779a957d7df8058ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37a97e38fffbca986dee7e2cb28bb794.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
您最近一年使用:0次
解题方法
9 . 椭圆
的左右焦点分别为
,
,其中
,
为原点.M是椭圆上任意一点,
且
.
(1)求椭圆的标准方程及离心率;
(2)过点
的斜率为
的直线
交椭圆于
两点.求
的面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dd54b9df3402ad91e2d34c40efe0c7a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5076289823db419f94e9c0c8f4aafd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3fb78c5f885034612c0e030b920143d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/385afe18c3fad66fdeadf74be824283c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f9515cfa7042107ed0ea7a3e409b91c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/105ecc8af696470d77ca96cc9117dfbd.png)
(1)求椭圆的标准方程及离心率;
(2)过点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1b6f209d1a805437046ca6ef79dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3fe95f656b98b53f71a9d72bf0c9a4b9.png)
您最近一年使用:0次
2023-12-11更新
|
130次组卷
|
2卷引用:宁夏银川市贺兰县景博中学2021-2022学年高二上学期期末考试数学(文)试题
名校
解题方法
10 . 已知椭圆
的对称中心为坐标原点,对称轴为坐标轴,焦点在
轴上,离心率
,且过点
.
(1)求椭圆
的标准方程;
(2)若直线
与椭圆交于
两点,且直线
的倾斜角互补,判断直线
的斜率是否为定值?若是,求出该定值;若不是,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5c7316976a221c051a2c14df80b1347.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fc1234aa2273bbae63aa9a3113e6620.png)
(1)求椭圆
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)若直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/790ef3382b1c731f2885eecfd92c2a86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
您最近一年使用:0次
2023-09-29更新
|
1750次组卷
|
10卷引用:宁夏银川市永宁县上游高级中学2023-2024学年高二上学期期中考试数学试题
宁夏银川市永宁县上游高级中学2023-2024学年高二上学期期中考试数学试题四川省成都市蓉城名校联盟2023届高三上学期第一次联考文科数学试题江西省上饶艺术学校2023-2024学年高二上学期10月月考数学试题广东省韶关市北江实验学校2023-2024学年高二上学期10月月考数学试题福建省南平市浦城第一中学2023-2024学年高二上学期期中数学试题(已下线)考点19 解析几何中的探索性问题 2024届高考数学考点总动员(已下线)第三章 圆锥曲线的方程(知识归纳+题型突破)-2023-2024学年高二数学单元速记·巧练(人教A版2019选择性必修第一册)(已下线)3.1.2 椭圆的简单几何性质(分层练习)-2023-2024学年高二数学同步精品课堂(人教A版2019选择性必修第一册)(已下线)黄金卷04(已下线)专题10 椭圆的几何性质8种常见考法归类(2)