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【背景说明】众所周知,以长方形的某一边为轴旋转一周,能够形成一个圆柱体,那么能不能利用这个动态形成的观点来求圆柱的体积呢?之所以提出这个问题,是源于一篇数学小故事,笔者阅读之后将此问题抛给许多老师,没想到引发了大家的热烈讨论,故事的主要部分如下:(聪聪和笨笨在玩一个长方形纸片做成的小风车)“你看,圆柱体是如何形成的呀?不就是一个长方形纸片旋转得到的吗?既然如此,以长方形的一条边为轴,就可以把圆柱体看成是好多个长方形纸片组
【Background】 As we all know, one side of the rectangle as the axis of a rotation for a week, can form a cylinder, then you can use this dynamic formation of the cylinder to create the point of view? The reason for this question is derived from a math A little story, the author after reading this question to many teachers, did not expect to lead to a heated discussion, the main part of the story are as follows: (Cong Cong and stupid playing a rectangular paper made of small windmill) ”You See how a cylinder is formed? Is not it a rectangular piece of paper that has been spun? In this case, taking an edge of a rectangle as an axis, you can think of a cylinder as a number of rectangular pieces of paper