1 . 舒腾尺是荷兰数学家舒腾设计的一种作图工具,如图,O是滑槽AB的中点,短杆ON可绕O转动,长杆MN通过N处的铰链与ON连接,MN上的栓子D可沿滑槽AB滑动.当点D在滑槽AB内做往复移动时,带动点N绕O转动,点M也随之而运动.记点N的运动轨迹为
,点M的运动轨迹为
.若
,
,过
上的点P向
作切线,则切线长的最大值为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1241216f3c1cb5e73043dd1037f556d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f3ffe7abc59e2f65d827c8eab8d36a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54298f581688081d0b0214334a0dedf2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02e47bb98258ebfcf1d8ad4bac10b7ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f3ffe7abc59e2f65d827c8eab8d36a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1241216f3c1cb5e73043dd1037f556d.png)
您最近一年使用:0次
名校
2 . 已知椭圆
的左,右焦点分别为
,直线
与椭圆
交于
两点,给出下列结论:①若
,则
;②
与
不可能平行;③若
,则
;④
与
不可能垂直.其中正确结论的序号为__________ (请把正确结论的序号全部填写在横线上).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9835aacabfaabdf7e61da1d4e08b225a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d2a97987f71835f519b462f5b8f5957.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acd55f837e9c4e6bba1163ef13edd09b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d73fbfd1b2f4b67ba5452bedcd1f5433.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2015d9a88fb4d8f0520790693abc9649.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f80ecb6b5d5eca464b3f099513c08fc5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c429b542abf0ebee74a239b4857cf88.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/288060bacca802a86ff209ddfd412e18.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d76a73553016ef953653c8d92cd14d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cabea664e61863b3b3279dbce607924e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e86dbcf83cd5d3421b3eed7be7dab32d.png)
您最近一年使用:0次