北师大版小学三年级数学下册除法部分讲课教案.ppt

北师大版三年级数学下册北师大版三年级数学下册Evaluation only.Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.蝴蝶与花蝴蝶与花.flv.flvEvaluation only.Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.问题：观察上面的图形，你能发现它们问题：观察上面的图形，你能发现它们有什么共同特征吗？有什么共同特征吗？Evaluation only.Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.活动要求：活动要求：1.把图形对称折一折，比较两把图形对称折一折，比较两侧的图形有什么特点，并画出侧的图形有什么特点，并画出折痕。折痕。2.思考：什么是轴对称图形？思考：什么是轴对称图形？Evaluation only.Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.折痕所在的直线就是轴对称折痕所在的直线就是轴对称图形的图形的对称轴对称轴。如果一个图形沿着一条线对折，如果一个图形沿着一条线对折，两侧的图形能够完全重合，这样的两侧的图形能够完全重合，这样的图形就是图形就是轴对称图形轴对称图形。Evaluation only.Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.并画出对称轴。并画出对称轴。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.如果给你一张白纸，你能剪出一个如果给你一张白纸，你能剪出一个好看的轴对称图形好看的轴对称图形?你有什么好方法？你有什么好方法？贝多芬-献给爱丽丝.mp3Evaluation only.Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.它它们们的的对对称称轴轴在在哪哪里里?用用虚虚线线画画出出来来.Evaluation only.Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.3.在方格纸上画出轴对称图形在方格纸上画出轴对称图形.Evaluation only.Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.它它是是轴轴对对称称图图形吗？形吗？Evaluation only.Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.1.找一找哪些数字、字母等是轴对称的。Evaluation only.Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.2.在点子图上画出轴对称图形在点子图上画出轴对称图形3.摆出轴对称图形Evaluation only.Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.看看哪些是对称图形，画出它们的对称轴。看看哪些是对称图形，画出它们的对称轴。有无数条有无数条对称轴。对称轴。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.本节课你学会了什么？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.