对于曲线
有以下判断:(1)它表示圆;(2)它关于原点对称;(3)它关于直线
对称;(4)
且
其中正确的有________ (填上相应的序号即可).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06f4f3d8ac7da6c1c186949ffc9c39a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d77f5191798242b7b9b88a75e17e4425.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a79d7f73b6128650bf7aed538260c72.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3eeafaa6479bcc807813868a124b56ff.png)
更新时间:2019-01-25 10:09:13
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【知识点】 轨迹问题
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【推荐1】在平面直角坐标系中,
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【推荐2】在平面直角坐标系
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