立足教材,选编课本原题,仿制课本类题,生成课本变题,是初中数学命题常用方法之一,体现了初中数学命题的公平性和基础性原则.“例题千万道,解后抛云霄”式的例题讲解很难达到提高解题能力,发展学生思维的目的.教师要善于钻研教材,用一双慧眼去发现具有典型性、可拓展性的例题或习题,善于做解后的反思,方法的归类,规律的总结和技巧的揣摩,继而进一步对例题进行挖掘、拓展、引申、评品,扩大例题的辐射面,这样的 Based on the textbook, select textbook original title, imitation textbook class questions, generate textbook problems, is one of the common method of junior high school mathematics proposition, embodies the junior middle school mathematics proposition fairness and basic principles. Sky "type of example is difficult to achieve to improve the ability to solve problems, develop the purpose of student thinking.Teachers should be good at studying materials, with a pair of eyes to find typical, scalable examples or exercises, good at reflection after the solution , Methods of classification, the law of the summary and skills to try to figure out, and then to further excavation, expansion, extension, evaluation of products, to expand the case of the radiation surface, so