e^2=a^2-b^2 is not an asumption, it is derived from 椭圆是到固定两点之和

e^2=a^2-b^2 is not an asumption, it is derived from 椭圆是到固定两点之和

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送交者: chouqilozi 于 2009-03-12, 14:38:45:

回答: e is half-distance between two foci 由 HunHunSheng 于 2009-03-12, 14:27:53:

等于常数, why do you say you assumed this?

How do you derive it? (无内容) - HunHunSheng (0 bytes) 2009-03-12, 14:44:58 (305831)
- here - chouqilozi (357 bytes) 2009-03-12, 14:53:19 (305841)
  - the triangle is messed up. when the point is in the middle of the two focal - chouqilozi (64 bytes) 2009-03-12, 14:56:14 (305847)
  - 最后两行假设了对称性。可是你凭什么可以假设对称？ (无内容) - HunHunSheng (0 bytes) 2009-03-12, 14:55:35 (305846)
    - Didn't assume, because - chouqilozi (108 bytes) 2009-03-12, 14:58:15 (305851)
      - 那你怎么知道轨迹会和两个焦点在一条直线上？ (无内容) - HunHunSheng (0 bytes) 2009-03-12, 15:12:48 (305860)
        
        昏君you lost me. (无内容) - chouqilozi (0 bytes) 2009-03-12, 15:18:59 (305874)