论文部分内容阅读
表格,用来统计各种数字,使人一目了然;用来综合比较各类问题,清晰明瞭。然而,人们往往只注意到了它的某些简单应用,其实,在许多趣味数学问题中,列表法有它独到之处。例1 将1～9这九个数字填入右图的空格里,使横、竖、斜线上的三数之和均为15。解:我们先设计一个9×9方格表,在表格的第i行第j列(i>i)填上数α_(ij),使i+j+α_(ij)=5且α_(ij)、i、j互不相同,这称为凑和表。从表中可以看出,数5出现
Forms are used to count various figures and make them clear at a glance. They are used to comprehensively compare various issues and are clear and concise. However, people often only noticed some of its simple applications. In fact, among many interesting mathematical problems, the list method has its unique features. Example 1 Fill in the 9 numbers from 1 to 9 in the space in the right figure so that the sum of the three numbers on the horizontal, vertical, and diagonal lines is all 15. Solution: Let’s first design a 9×9 grid table, fill in the number α_(ij) in the i-th row and j-th column (i>i) of the table so that i+j+α_(ij)=5 and α_(ij). ), i, and j are different from each other. This is called Minato and Table. As can be seen from the table, the number 5 appears