相似形是初中几何的重要内容之一,也是进一步学习其他几何知识的基础.同学们在学习相似形的过程中,常出现判定定理、性质定理混淆不清及思考问题不周全等错误. 现将一些典型的错解剖析如下. 例1 设k=a+b-c/c=a-b+c/b=-a+b+c/a,则k=_______. 错解:由等比性质,得k=(a+b-c)+(a-b+c)+(-a+b+c)/a+b+c=1. Similarity is one of the important contents of junior high school geometry, and it is also the basis for further study of other geometric knowledge. During the course of learning similar forms, the students often make mistakes such as the determination theorem, the property theorem confused, and the problem of imperfect thinking. Some typical misinterpretations are as follows. Example 1 Let k=a+bc/c=a-b+c/b=-a+b+c/a, then k=_______. k=(a+bc)+(a-b+c)+(-a+b+c)/a+b+c=1.