![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/359b033b5bb5c9eaac95a096dd39b6003af3b365?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
看看答案对吗
追答N的话你可以自己想想,并不难
追问谢谢 如果定点在椭圆外部呢?
追答等等,我再给你写下。我有点大意
追问![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/b219ebc4b74543a9b96274b916178a82b901144d?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/94cad1c8a786c917881adb4cc13d70cf3bc757ae?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
这样写对吗?
追答![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/5243fbf2b211931311b476c56d380cd790238dd4?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
原题中不是还乘了个e分之一吗
追问![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/314e251f95cad1c853217452773e6709c93d5129?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
追答![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/b7003af33a87e950acdc7b1918385343faf2b4f8?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
追问![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/730e0cf3d7ca7bcb76c74c5ab6096b63f624a803?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
追答因为pf1前面有系数e分之一
追问如果没有1/e 就一般情况下 椭圆内有定点 椭圆上有动点 是直接连线吗
追答对的(^_^)
追问为什么有时候要用2a-pf2来换?
追答因为有时候问题 没办法直接用 两边之和大于第三边或者两边之差小于第三边解决,这时候需要转化
追问如果定点在椭圆外是不是直接连线呢?
追答你可以自己总结一下,印象会更深刻
追问嗯嗯多谢😊
追答不客气
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