化归是中学数学基本的思想方法之一,数学研究的过程自始自终贯穿着“化生为熟、化繁为简”,再复杂的数学问题都可以通过化归使问题得到解决.它既是一种数学思想,也是一种数学能力.但在化归时常出现:(一)转化方向错误,(二)转化本质上的不等价.如何防止转化的失误要注意两点:(一) The transformation is one of the basic methods of thinking in middle school mathematics. The process of mathematics research has always been dressed from the beginning to the end of life as “a metaphysic is cooked, a variety of things is simplified,” and then complex math problems can be resolved through transformation. It is not only a mathematical idea, but also a mathematical ability. However, it often appears in the transformation: (a) the wrong direction of conversion, (b) the inequality of the transformation. How to prevent conversion mistakes should pay attention to two points: (a)