1 . 参数方程是以参变量为中介来表示直线或曲线上点的坐标的方程,是直线或曲线在同一坐标系下的另一种表现形式.很多曲线(如心脏线、螺线、玫瑰线)都可以用参数方程呈现.在平面直角坐标系
中,直线
的参数方程式
(
为参数),其中
,角
为直线
的倾斜角.曲线
的参数方程是
(
为参数).其中
,直线
与曲线
相交于
、
点.
(1)根据以上的参数方程求出直线
的一般式方程和曲线
的标准方程;
(2)设点
,设点
对应的参数为
,试证明:
;
(3)试问是否存在角
,使得对于任意的点
,表达式
均为定值
,若存在,请求出
及值
(结果用
,
表示);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/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9b1cf149172b6c4a6526b25aba683be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a1d5e2dfa2d5b134c85995877eff156b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73dd51ce19cf9b0ebfa8e42190c72bbf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.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/e77eee60e92c3e08a5877062cd1e925f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a990942b9fa26d28cee8579325da3675.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a0c4c098615c6bc7e6dcf72e5b5201a.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/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
(1)根据以上的参数方程求出直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)设点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93bb2baf350ed7e3490fd9e7399ce5c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d9fd58e71dcae6cafaf9037d20ebd76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39b1c2f6f5103b4a981e417b620dd239.png)
(3)试问是否存在角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93bb2baf350ed7e3490fd9e7399ce5c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6df16c0ff148acd2c4eac082120e43be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/291f17141e5dfbb8e129a9e59d23c120.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
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名校
2 . 在平面直角坐标系
中,对于任意一点
,总存在一个点
满足关系式
,则称
为平面直角坐标系中的伸缩变换.
(1)在同一直角坐标系中,求平面直角坐标系中的伸缩变换
,使得椭圆
变换为一个单位圆;
(2)在同一直角坐标系中,
(
为坐标原点)经平面直角坐标系中的伸缩变换
得到
,记
和
的面积分别为
与
,求证:
;
(3)若
的三个顶点都在椭圆
上,且椭圆中心恰好是
的重心,求
的面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee31829d0d4d5f779a957d7df8058ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aee82283f06cedef32eb15b87964f5d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/495984a7f99222eb03bf296260fac7b1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/882fe79977fce2cc7c289b0da1721c2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6581916f5a65edfea257c804efee007e.png)
(1)在同一直角坐标系中,求平面直角坐标系中的伸缩变换
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe4f007b1ceaccfff1d659f6f8592c4e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/78847dd23bb54d5d960016e6beeb5713.png)
(2)在同一直角坐标系中,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/866b81a8384cce4f24867baca2e6820c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/882fe79977fce2cc7c289b0da1721c2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a21e44af368f3336354704d92609f9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/866b81a8384cce4f24867baca2e6820c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a21e44af368f3336354704d92609f9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/150a135bbd528daf3f19a58a621a57c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/793b3bfc799e7cd6a795324ca02aaa23.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36e5e61804ce550636a0354e0a78a22d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48da128547c4cf9745e8e4b99988a3db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36e5e61804ce550636a0354e0a78a22d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36e5e61804ce550636a0354e0a78a22d.png)
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2卷引用:上海市七宝中学2023届高三上学期元月模拟数学试题
3 . 如图所示,已知半圆O的直径为
,l为位于半圆之外,而又垂直于
延长线的一直线,其垂足为T,且
,又M,N是半圆上的不同的两点,
,
,且
.求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dea2ae9d515f9ab351ad72306b776ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e7acd656195631c58a22b060c0d3ab9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f5903d670301ba4abbfda6324be1a30.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68d9c9b2c01681fab7d312271a860e46.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8bec9ebcbb0a854dfe16b90a7894c9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab14817a0fe0920d012bf0d81ede4f0a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/28/0658cae7-9fee-442b-a262-8750ef39329d.png?resizew=188)
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2卷引用:高中数学解题兵法 第三十三讲 命题之间的转化与变换
2022高三·全国·专题练习
解题方法
4 . 已知椭圆
,设直线
不经过点
的直线交于
两点,若直线
的斜率之和为
,证明:直线
恒过定点.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c82e7d9f4f7ace849e09e9adcb786b7f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22840186db0afc0e2b2e8915ce79b998.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/acbc6a613224461ade69362d46550474.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://img.xkw.com/dksih/QBM/2022/1/17/2896404571561984/2923463462461440/STEM/11c2c5d2-d672-4425-b4fd-729ab3a62033.png?resizew=222)
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6卷引用:解密14 椭圆及其方程(讲义)-【高频考点解密】2022年高考数学二轮复习讲义+分层训练(新高考专用)
(已下线)解密14 椭圆及其方程(讲义)-【高频考点解密】2022年高考数学二轮复习讲义+分层训练(新高考专用)(已下线)专题41 定比点差法、齐次化、极点极线问题、蝴蝶问题(已下线)专题13 圆锥曲线压轴解答题常考套路归类(精讲精练)-2(已下线)重难点突破18 定比点差法、齐次化、极点极线问题、蝴蝶问题(四大题型)(已下线)专题18 圆锥曲线高频压轴解答题(16大题型)(练习)(已下线)大招17超级韦达定理
5 . 如图所示,在平面直角坐标系
中,P是不在x轴上的一个动点,过点P可作抛物线
的两条切线,两切点A、B的连线与
垂直.设直线
与直线
与x轴的交点分别为Q、R.
![](https://img.xkw.com/dksih/QBM/2021/9/24/2815037014687744/2815804218966016/STEM/6577450b-894a-4048-a6d1-ee81f24bcd36.png?resizew=234)
(1)证明:R是一个定点;
(2)求
的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee31829d0d4d5f779a957d7df8058ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/745de5ef1fd897d16e37464172d5e8c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef49a3ca580a144cc65a609c167facc1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef49a3ca580a144cc65a609c167facc1.png)
![](https://img.xkw.com/dksih/QBM/2021/9/24/2815037014687744/2815804218966016/STEM/6577450b-894a-4048-a6d1-ee81f24bcd36.png?resizew=234)
(1)证明:R是一个定点;
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f50c707d0350c121c6a611db39a5e85d.png)
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3卷引用:2014年全国高中数学联合竞赛试题
解题方法
6 . 具有公共焦点、公共对称轴的两段圆锥曲线弧合成的封闭曲线称为“盾圆”.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/18/115ff7c5-c128-484e-911f-e298b0d241f3.png?resizew=130)
(1)如图所示,已知“盾圆D”的方程为
设“盾圆D”上的任意一点M到
的距离为
,M到直线
的距离为
,求证:
为定值;
(2)由抛物线弧
,
与椭圆弧
所合成的封闭曲线为“盾圆E”.设过点
的直线与“盾圆E”交于A、B两点,
,
,且
(
),试用
表示
,并求
的取值范围.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/18/115ff7c5-c128-484e-911f-e298b0d241f3.png?resizew=130)
(1)如图所示,已知“盾圆D”的方程为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80709beba617c323810ead791a716910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/092fd1b1d33979818300cd2e3699bff7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5edf900c810371fb21297c15f86d8743.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e2977eea43a781e06d93e04a395a309.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b31ac1def558351e2e3ed1235c570530.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2a4b32d388558eb9a9e4f0f2dd57c09.png)
(2)由抛物线弧
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/522230546d4b802094e86ceb48c2ba38.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f39172ebd6d364eede85f010f211ed2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e35423ad99a9f081115cf26b0ab10aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/092fd1b1d33979818300cd2e3699bff7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2788a6f7e841ac39c6c45b0fb83e1fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ecf753e5d386ae18d90632869a7c816.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18dd43917e517b28afa090e3126c496a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9c89eab34f319912ed5efb3f6f4592c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d66c03d4ca06819a6ce7fc8ea6de0f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2858005b9ae89ae080d83dcc13cf8e81.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4de53ee7fb99c9c6b185bb80c8d8e9e2.png)
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2020·全国·模拟预测
7 . (本小题满分10分)选修4-4:坐标系与参数方程
在平面直角坐标系
中,曲线C的参数方程为
(
为参数).在以坐标原点为极点,x轴的正半轴为极轴的极坐标系中,直线l的极坐标方程为
.
(1)求曲线C的普通方程及直线l的直角坐标方程;
(2)求曲线C上的点到直线l的距离的最大值与最小值.
(本小题满分10分)选修4-5:不等式选讲
已知
.
(1)求不等式
的解集;
(2)若
的最小值为M,且
,求证:
.
在平面直角坐标系
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee31829d0d4d5f779a957d7df8058ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/334e3a17bdb2273b59b4fa2e8c752ee9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6581916f5a65edfea257c804efee007e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc99e3533e86d24d47630cb4ee209695.png)
(1)求曲线C的普通方程及直线l的直角坐标方程;
(2)求曲线C上的点到直线l的距离的最大值与最小值.
(本小题满分10分)选修4-5:不等式选讲
已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4fd6d69f12975d53bf7eebda2e17388.png)
(1)求不等式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/013ffa2f0de8ab4176247c53bcd8ce7b.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9975c406221e50c29970483385aeb3d0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5af5a0bf00894d969fdc57e4119260f.png)
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名校
8 . 在直角坐标系
中,直线
的参数方程为,
,(
为参数).以坐标原点为极点,以
轴的正半轴为极轴,建立极坐标系,圆
的极坐标方程为
.
求证:直线
与圆
必有两个公共点;
已知点
的直角坐标为
,直线
与圆
交于
,
两点,若
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee31829d0d4d5f779a957d7df8058ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80ec4ec4b327af5ca3338b5045a707aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2837cc78b93d301232934bcaf5fe8e1c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9bf6c84731e5e1bd335ecfc2d36c3d81.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/1f53190d6ead827a6338b9de847aeaf1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d7a999c36de5c9a9ce876a4a56fa34c.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/913181ad4837c0c633367878d2d34d26.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d66c03d4ca06819a6ce7fc8ea6de0f0.png)
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2020·全国·模拟预测
9 . (本小题满分10分)选修4-4:坐标系与参数方程
在平面直角坐标系
中,曲线C的参数方程为
(
为参数).在以坐标原点为极点,x轴的正半轴为极轴的极坐标系中,直线l的极坐标方程为
.
(1)求曲线C的普通方程及直线l的直角坐标方程;
(2)求曲线C上的点到直线l的距离的最大值与最小值.
(本小题满分10分)选修4-5:不等式选讲
已知
.
(1)求不等式
的解集;
(2)若
的最小值为M,且
,求证:
.
在平面直角坐标系
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee31829d0d4d5f779a957d7df8058ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dfa0ab7cef6373f5d1d7af3cd99f2666.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6581916f5a65edfea257c804efee007e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc99e3533e86d24d47630cb4ee209695.png)
(1)求曲线C的普通方程及直线l的直角坐标方程;
(2)求曲线C上的点到直线l的距离的最大值与最小值.
(本小题满分10分)选修4-5:不等式选讲
已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4fd6d69f12975d53bf7eebda2e17388.png)
(1)求不等式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/013ffa2f0de8ab4176247c53bcd8ce7b.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9975c406221e50c29970483385aeb3d0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5af5a0bf00894d969fdc57e4119260f.png)
您最近一年使用:0次
10 . 已知椭圆
:
经过点
,离心率为
,点
为椭圆
的右顶点,直线
与椭圆相交于不同于点
的两个点
.
(1)求椭圆
的标准方程;
(2)当
时,求
面积的最大值;
(3)若
,求证:
为定值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48da128547c4cf9745e8e4b99988a3db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e684712aade8dcebb62716843791034.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/860884c0017c8bceb5b0edff796c144f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.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/455bae796d928c3c4d9090e924259628.png)
(1)求椭圆
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5f55f82a88eb037a47971d8b3b9ca34.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea1f0417d8269f01d8e0bc1a8756e2ac.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d67b5094972b896be121964f3b0be6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c9e5716211c9f31e1cd910ccf352c95.png)
您最近一年使用:0次