zimu_003
幼苗
共回答了25个问题采纳率:76% 举报
这个题目有点乱……
如果理解成:[x/(x²-2xy+y²)]*[(x²-y²)/(x+y)]+(2x+2)/(x-y)-2
则化简:
=[x/(x-y)²]*[(x+y)*(x-y)/(x+y)]+(2x+2)/(x-y)-2
=x/(x-y)+(2x+2)/(x-y)-2
=[x+(2x+2)-2(x-y)]/(x-y)
=(x+2y+2)/(x-y)
带入给定的条件,得到的值为:
-1
根据最后得到的结果来看,题目应该没有理解错.
祝好运.
1年前
8