《中小学数学》(初中教师版)2009年第3期张玉明老师《对一道中考题解法的纠错》一文,对2007年青岛市中考数学题进行了认真分析,用穷举法给出了一种很好的解答.但是张老师在后半部的“例如”却存在一些欠缺,问题表现在:1·解析中S1、S2、S3计算均有误(可能是笔误),正确的表达式? “Primary and secondary mathematics” (junior high school teacher version) 2009 the third period ZhangYuMing teacher “on a secondary school entrance examination solution error correction” one article, 2007 Qingdao city math test conducted a careful analysis, with exhaustive method gives a However, there is some deficiency in the “example” of Zhang in the latter half. The problems are as follows: 1. The correct expressions (which may be clerical mistakes) are calculated in S1, S2 and S3 in the analysis?