六年级数学《倒数的认识》PPT课件苏教版.ppt

苏教版小学六年级数学倒数的认识高邮市卸甲镇伯勤小学曹天平 Evaluation only. Evaluation only. Created with Client Profile . Created with Client Profile . Copyright 2004-2011 Aspose Pty Ltd. Copyright 2004-2011 Aspose Pty Ltd. ??3 88 3??7 13 13 7 ??3 131 11 1 观察这几个算式。你有什么发现? ?? 6 55 6 Evaluation only. Evaluation only. Created with Client Profile . Created with Client Profile . Copyright 2004-2011 Aspose Pty Ltd. Copyright 2004-2011 Aspose Pty Ltd. 1的两个数吗? Evaluation only. Evaluation only. Created with Client Profile . Created with Client Profile . Copyright 2004-2011 Aspose Pty Ltd. Copyright 2004-2011 Aspose Pty Ltd. 每个算式中两个数相乘的积是 1。乘积是 1的两个数叫做互为倒数。 Evaluation only. Evaluation only. Created with Client Profile . Created with Client Profile . Copyright 2004-2011 Aspose Pty Ltd. Copyright 2004-2011 Aspose Pty Ltd. 38 83 和互为倒数,就是的倒数是,的倒数是。 3838 83 83 请你举例说明谁是谁的倒数? 怎么检验两个数是不是互为倒数? Evaluation only. Evaluation only. Created with Client Profile . Created with Client Profile . Copyright 2004-2011 Aspose Pty Ltd. Copyright 2004-2011 Aspose Pty Ltd. 互为倒数的一组数具有什么特点? 3 88 3和7 10 10 7和5 4 分子和分母调换了位置 4 5和 Evaluation only. Evaluation only. Created with Client Profile . Created with Client Profile . Copyright 2004-2011 Aspose Pty Ltd. Copyright 2004-2011 Aspose Pty Ltd. 写出、的倒数。 35 53 分子、分母调换位置 23 分子、分母调换位置 32 5 33 2 Evaluation only. Evaluation only. Created with Client Profile . Created with Client Profile . Copyright 2004-2011 Aspose Pty Ltd. Copyright 2004-2011 Aspose Pty Ltd. 下面数的倒数各是多少? 11 3 10 7 610 179 4 3 27 5 8 Evalu