微课(小学四年级数学)复习进程.ppt

单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,直线、射线和角,贵州省铜仁市万山区田坪小学 肖宗林,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,有只虫子从一个山洞到别一个山洞寻找食物,有五条路可走,可是走哪一条路最短呢,?,可怜的,小虫子犯愁了,谁能帮帮它呢,?,起点,终点,1,2,3,4,5,这条线是直的,!,广州市三学苑网络科技有限公司,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,在生活中你发现,哪些是直的线,?,广州市三学苑网络科技有限公司,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,直线,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,直线,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,直线,：没,有端点，可以向两端无,限延长，,不可度量长度。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,像手电筒、汽车灯和太阳等射出来的光线，,都可以近似地看成是,射线,。,想一想：射线有哪些特点呢,？,广州市三学苑网络科技有限公司,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,射线,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,射线,：只,有一个端点，可以向一端无,限延长，,不可度量长度。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,直线,线段,有两个端点，有限长，能够测量长度。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,射线、线段都是直线的一 部分。,直线,射线,线段,线段,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,直线,射线,线段,区,别,联系,直线、射线、线段之间的联系和区别。,没有端点，无限长，不可度量。,只有,一个,端点，无限长，不可度量。,有,两个,端点，有限长，,可以度量。,都是,直的,，射线和线段都是,直线的一部分。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,判断哪些是直线、线段和射线？,广州市三学苑网络科技有限公司,（,1,）,（,3,）,（,2,）,（,7,）,（,4,）,（,6,）,（,5,）,（,9,）,（,8,）,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,从一点出发能画,(),条射线,.,无数,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,如果从一点引出,两条射线,会是什么图形呢？,顶点,边,边,角,从,一点,引出,两条射线,所组成的图形叫做角,.,3,记作,:3,读作,:,角,3,角的符号：,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,思考：角的大小与什么有关？,1,、角的大小与两条边的长短无关。,2,、角,的,大小与,两边叉开的大小,有关，叉开大、角就大，叉开小、角就小。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,神奇夺宝之旅,准备好了吗,?,开始吧,!,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,(1),(2),(3),(4),(5),(6),线段：（,3,）,直线：（,1,）（,5,）,射线：（,2,）（,6,）,下面哪些是线段，哪些是直线，哪些是射线。,第一关,火眼金睛,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,第二关,明辨是非,从一点引出两条射线所组成的图形是角,。,线段有两个端点,射线只有,1,个端点,直线没有端点,。,一条直线长,1.5,米。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,第三关,直线、射线和,线段中无限长,的有（）,确定角的,大小要看,（）,把一个角的两,条边分别延长，这时角的大小（,）,、直线和射线,、直线和线段,、射线和线段,、边的长短,、两条边叉开的大小,、比原来大,、比原来小,、跟原来一样,选一选,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,第四关,数一数，下图中各有几个角？,个,个,胜利在望！,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,经过一点能画,(),条直线。,第五关,无数,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,经过两点能画,(),条直线,一,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,第六关,下图中一共有（）条直线，,（）条射线，（）条线段。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,闯关成功！你真棒！,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,