贵刊 2 0 0 2年第 7期刊登了两篇关于求阴影面积的文章 .可谓思路新颖 ,方法独特 ,值得学习和借鉴 .对于某些阴影面积的问题 ,运用整体思维 ,可以简便地得到解答 ,现以上述两篇文章中的部分例题为例 ,加以说明 .图 1如图 1 ,ＡＢＣＤ是边长为ａ的正方形 ,分别以各顶点为圆心 , You published two articles on the area of ​​shadows in the 7th issue of your magazine in 2000. It is a novel and unique method and worthy of learning and learning. For some shadow area problems, the overall thinking can be easily answered. Some of the examples in the above two articles are taken as an example to illustrate. Figure 1 As shown in Figure 1, ABCD is a square with a side length of a, with each vertex as its center.