因式分解(x+y)²-4(x+y-1)
问题描述:
因式分解(x+y)²-4(x+y-1)
答
解
(x+y)²-4(x+y-1)
=(x+y)²-4(x+y)+4
=[(x+y)-2]²
=(x+y-2)²