1、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,*,also lack the necessary understanding.Two is the business foundation is not solid,the text level is not high.Their work in the army before,although the understanding of the material,but also just only know fur,te
2、xt level,writing ability is still in a low level interface.The knowledge is not complete,especially it is very little about professional some departments know knowledge,to write Chinese but not false,sometimes rely on online writing or presentation of ready-made one-sided materials,unwilling to make
3、 a deep thinking,put all sorts of things together,the presentation quality is not high,due to the overall quality of their own quality is not high,the leadership of departments can not understand,it is difficult to stand in the perspective,also lack the necessary understanding.Two is the business fo
4、undation is not solid,the text level is not high.Their work in the army before,although the understanding of the material,but also just only know fur,text level,writing ability is still in a low level interface.The knowledge is not complete,especially it is very little about professional some depart
5、ments know knowledge,to write Chinese but not false,sometimes rely on online writing or presentation of ready-made one-sided materials,unwilling to make a deep thinking,put all sorts of things together,the presentation quality is not high,due to the overall quality of their own quality is not high,t
6、he leadership of departments can not understand,it is difficult to stand in the perspective,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,*,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,*,人教版六年级数学下册数学思考PPT,六年级下,数学思考,巧数线段,握一握 说一说,.,小组内的,4,个同学,每两个握一次手,一共可以握几次?,思考:怎样
7、做到不重复,不遗漏,有顺序,一共握了:,6,次,1+2+3=6(,次,),8,个同学可以握多少次呢?我们教室里的,40,个同学又可以握多少次呢?有没有什么规律?,我们可以从2个点开始,逐步增加点数来研究。,合作探究 发现规律,小组合作要求:,连一连,完成表格,说一说你们的发现,A,B,A,B,C,A,B,C,D,仔细观察这张表格,你能得到什么信息?,3,个点共连:,1+2=3,(条),4,个点共连:,1+2+3=6,(条),5,个点共连:,1+2+3+4=10,(条),根据规律,,8,个点能连几条线段?,问题,1,2,3,4,5,6,7,能用简单方法计算吗?,=28,(条),=83,4,=,(
8、1,7),(2,6,),(3,5),4,根据规律,你知道,15,个点能连多少条线段吗?,问题,1,2,3,4,5,6+14,=,105,(条),15,个点,=,15,7,按照简单的方法计算,你发现了什么,试着归纳一下。,n个点共连成线段:,1+2+3+4+5+6+(n-1),再观察,2,3,5,4,点数,增加条数和总条数之间有什么联系吗?你还有什么新发现吗?,可以发现:,3,个点共连:,322=3,(条),4,个点共连:,432=6,(条),5,个点共连:,542,=10,(条),n个点共连成线段:,n,(n-1),2,n个点共连成线段:,1+2+3+4+5+6+(n-1),n,(n-1),2
9、,今天,我们一共有,40,个同学,,每,2,位好朋友握手,1,次,大家一共要握手多少次?,1+2+3+.+39,=,(,1,39,),19,20,=780,(次),算一算,1+2+3+.+39,=40392,=780,(次),答:,40,个同学一共要握手,780,次,同学们,在我们生活中有许多看似复杂的问题,我们都可以尝试从简单问题去思考,逐步找到其中的规律,从而来解决复杂的问题。,1.有几条线段?,举一反三,2.,有几个角?,3,2,1,2,1,9,8,7,6,4,5,3,4,5,8,7,6,1+2+3+4+5+6+7+8,=(1+8),4,=36,(条),98,2=36(,条,),1+2+
10、3+4+5+6+7,=,(,17,),3,+4,=28,(个),87,2=28(,个,),三、巩固深化,1.,观察下图,想一想。,(1),第,7,幅图有多少个棋子?第,15,幅图呢?,每幅图各有多少个棋子?,1 4 9 16,在数的过程中,你发现了什么?,问题,1 4 9 16,1,1 2,2,3,3,4,4,每行的棋子数,行数棋子总数,问题,1.,第,7,幅图有多少个棋子?第,15,幅图呢?,77,49,(个),1515,225,(个),2.,第,n,幅图每边有多少个棋子?一共有多少个棋子?,每行有,n,个,有,n,行,棋子总数,=,n,2,今天你学到了什么?,从简单开始,有序思考,用化繁为
11、简,找到规律,复杂的问题要善于退,,足够地退,,退到最原始而不失去重要性的地方,,是学好数学的一个诀窍。,谢谢!,不足之处,恳请大家给予批评指正,多边,形,边 数,3,4,5,6,内角和,180,360,540,720,(,1,)多边形内角和与它的边数有什么关系?,(,2,)一个九边形的内角和是多少度?,多边形内角和(边数,-2,),180,(,9-2,),180,1260,1+2+3+4+5=15,(条),1+2+3+4+5+6+7=28,(条),A,B,A,B,C,A,B,C,D,A,B,C,D,E,找规律,(,1,),3,,,9,,,11,,,17,,,20,,,36,,,41,,,+2 +3 +4 +5,(,2,),1,,,3,,,2,,,6,,,4,,,12,,,+3 +3 +3 +3,2 2 2 2,26,30,9,8,16,+6 +6 +6 +6,此课件下载可自行编辑修改,仅供参考!感谢您的支持,我们努力做得更好!谢谢,