https://changzh.me/tags/%E5%9D%90%E6%A0%87%E5%8F%98%E6%8D%A2/Recent content in 坐标变换 on Blog of BrianHugozh-CNSat, 19 Sep 2026 23:09:00 +0800https://changzh.me/posts/ellipse-to-circle-geometry/Sat, 19 Sep 2026 23:09:00 +0800https://changzh.me/posts/ellipse-to-circle-geometry/通过坐标伸缩把椭圆化为圆，推导切点坐标与一个弦长平方和恒等式，并说明哪些几何关系可以保留。