逻辑划分在几何的常规题中也有广泛的应用.下面补充几例供研究与讨论. 例1在△ABC中,AB、AC边上的高分别为CE、BF,E、F分别为垂足,D为BC的中点.如果乙召通C。“,乙ED声’=尹,试求:(1)y与x之间的数量关系,用含x的代数式表示y,并写出x的取值范围;(2)x=60时,y的对应值,并判断△DEF Logical partitioning is also widely used in geometrical general problems. Here are some examples for research and discussion. Example 1 In △ABC, the heights on the sides of AB and AC are CE and BF, respectively. E and F are pesudopods, respectively. D is the midpoint of BC. If B calls C. ", B ED sounds = Yin, try to: (1) the quantitative relationship between y and x, use algebraic expressions containing x to represent y, and write the range of values ​​for x; (2) x = 60, y The corresponding value and determine △DEF