“化归”是一种重要的思维方法,在数学竞赛的解题中,有广泛的应用。教学时从不同的角度,有意识地培养化归思维,促使学生多方联想,触类旁通,去寻找解题的捷径,能有效地提高解题能力。一、抽象“条件”具体化。题目:甲乙两人在400米的环形跑道上进行800米赛跑,甲自始至终匀速前进,乙第二圈的速度 “Transition” is an important way of thinking. It has a wide range of applications in solving problems in the mathematical competition. In teaching, from a different perspective, consciously nurturing the mindset, urging students to associate with each other, comprehend by analogy, and find shortcuts to solve problems, can effectively improve the ability to solve problems. First, the abstraction of “conditions”. Title: The 800-meter race between A and B on a 400-meter ring track, A continues at a uniform speed from start to finish, and the speed of the second lap B