Download - 角的初步认识
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![Page 1: 角的初步认识](https://reader031.vdocuments.pub/reader031/viewer/2022020921/56812ddf550346895d933618/html5/thumbnails/1.jpg)
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直线
1 、直线的线是直的 ,
2 、可以向两端无限延长 ,
3 、直线没有端点 .
![Page 3: 角的初步认识](https://reader031.vdocuments.pub/reader031/viewer/2022020921/56812ddf550346895d933618/html5/thumbnails/3.jpg)
线 段
线段的线是直的 ,
线段是有一定长度的 ,
线段有两个端点 .
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.射 线
思考 : 射线有什么特点 ?
射线的线是直的 ,
射线是无限长的 ,
射线只有一个端点 .
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从一点出发可以画无数条射线。从一点出发可以画无数条射线。
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顶点顶点
边边
边边
![Page 7: 角的初步认识](https://reader031.vdocuments.pub/reader031/viewer/2022020921/56812ddf550346895d933618/html5/thumbnails/7.jpg)
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√ √×
×× √
小马
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下面图形有几个角?
3 个角 4 个角
3 个角
![Page 13: 角的初步认识](https://reader031.vdocuments.pub/reader031/viewer/2022020921/56812ddf550346895d933618/html5/thumbnails/13.jpg)
比一比,哪个角大?
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一张长方形的纸有 4 个角,用剪刀剪一刀,剪去一个角,还剩几个角?