对抛物线
:
,有下列命题:
①设直线
:
,则直线
被抛物线
所截得的最短弦长为4;
②已知直线
:
交抛物线
于
、
两点,则以
为直径的圆一定与抛物线的准线相切;
③过点
与抛物线有且只有一个交点的直线有1条或3条;
④若抛物线
的焦点为
,抛物线上一点
和抛物线内一点
,过点
作抛物线的切线
,直线
过点
且与
垂直,则
平分
;
其中你认为是正确命题的所有命题的序号是______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e42102c1c07562853219ca5918803a27.png)
①设直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6767830cc1811f0f4ea5a008fdc7e723.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
②已知直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6767830cc1811f0f4ea5a008fdc7e723.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/f52a58fbaf4fea03567e88a9f0f6e37e.png)
③过点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36ca880518233b7265bc2a3b95cad16f.png)
④若抛物线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ab3c75d42587ba6174ccce153f4020d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a06292914b5d9e0608524e8d53869b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e9b0f5f44abbc6544a2f672b025b013.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f6f17bc385bafb37e8f964e5eb99cd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e9b0f5f44abbc6544a2f672b025b013.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f6f17bc385bafb37e8f964e5eb99cd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43b1d758c94b6d96a420c383d3072870.png)
其中你认为是正确命题的所有命题的序号是
更新时间:2020-12-11 10:14:28
|
相似题推荐
填空题-单空题
|
适中
(0.65)
【推荐1】在圆
上任取一点,则该点到直线
的距离不小于
的概率为__
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f240cccaf24af8a796abb95cb42be52e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6912940c64a0bdb698c9af82fd2b7600.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4b8503f4706b8321e4e79a87eadea84.png)
您最近一年使用:0次
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【推荐2】已知圆C的方程为
,定点
,直线
有如下两组论断:
![](https://img.xkw.com/dksih/QBM/2011/7/27/1570274036809728/1570274042265600/STEM/d5f47c1df76e46b4becb9d94a7c2f4c9.png?resizew=430)
由第Ⅰ组论断作为条件,第Ⅱ组论断作为结论,写出所有可能成立的命题
(将命题用序号写成形如p
q的形式)_________________________________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3503d330608e7138d1b529aba4512fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3511cdc6a9b56bc1d9415d3d94ef0f67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cde1e24c466423ad9e24585f4a436962.png)
![](https://img.xkw.com/dksih/QBM/2011/7/27/1570274036809728/1570274042265600/STEM/d5f47c1df76e46b4becb9d94a7c2f4c9.png?resizew=430)
由第Ⅰ组论断作为条件,第Ⅱ组论断作为结论,写出所有可能成立的命题
(将命题用序号写成形如p
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ef73aff3fe470e367f4af24fdfff3df.png)
您最近一年使用:0次
【推荐1】过抛物线
的焦点
作两条互相垂直的弦
、
,若
与
面积之和的最小值为32,则抛物线的方程为_________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13151e6907f89fbe166f74ec47d3a825.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54fb6e81fee5674c3e26a65e58cc506d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7e64c953aaf341e772a5fe776fbc78a.png)
您最近一年使用:0次
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解题方法
【推荐2】已知
为抛物线
:
上一点,
为焦点,过
作
的准线的垂线,垂足为
,若
的周长不小于48,则点
的纵坐标的取值范围是________ .
![](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/9a3bdbd625645e0ecb7be1dc82b59d1e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.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/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21871e06601d895874b1b8a49b1b808f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
您最近一年使用:0次
填空题-单空题
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适中
(0.65)
解题方法
【推荐1】抛物线具备有趣的光学性质:由焦点射出的光线经过抛物线反射后,会沿着平行于抛物线对称轴的方向射出.已知抛物线
的焦点为F,AB为抛物线的过点F的一条弦,若从点F发出的光线分别在点A和点B反射后得到的两条平行直线之间的距离为5,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88bee8e70f1fab639be1636c7bce0477.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/745de5ef1fd897d16e37464172d5e8c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88bee8e70f1fab639be1636c7bce0477.png)
您最近一年使用:0次
【推荐2】已知抛物线
的焦点为F,已知第一象限的点A在抛物线上,连接AF并延长交抛物线于另一点B,且
,则
的面积是___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ac62b1ade07205ae2693ec1ab135def.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d780f0607ef7e19996aa5274409cd103.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/866b81a8384cce4f24867baca2e6820c.png)
您最近一年使用:0次
填空题-单空题
|
适中
(0.65)
【推荐1】已知以F为焦点的抛物线
上的两点A,B满足![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84b8a2a41a8b50e10d68943e3f0f4e05.png)
,则弦AB中点到准线的距离为_____________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/745de5ef1fd897d16e37464172d5e8c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84b8a2a41a8b50e10d68943e3f0f4e05.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a78ba761e6d109bfd7e52e0f66c1ea4.png)
您最近一年使用:0次
填空题-单空题
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适中
(0.65)
解题方法
【推荐2】F为抛物线
的焦点,过F且斜率为k的直线l与抛物线交于P、Q两点,线段
的垂直平分线交x轴于点M,且
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/995e31d67e547f5129de48dac3fa688e.png)
__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1bb4dd4670828f75bc573b52cdd02e1d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99ffac516145b99309bc1b248fc625ae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/995e31d67e547f5129de48dac3fa688e.png)
您最近一年使用:0次