题目

分式约分:(y+z-x)/{x^2-(y+z)^2}

提问时间：2020-12-27

答案

(y+z-x)/{x^2-(y+z)^2}
=(y+z-x)/[(x-y-z)(x+y+z)]
=-(x-y-z)/[(x-y-z)(x+y+z)]
=-1/(x+y+z)