(x-2)^2-2x+2y+1
问题描述:
(x-2)^2-2x+2y+1
答
(x-y)²-2x+2y+1=(x-y)²-2(x-y)+1
=(x-y-1)²
(x-2)^2-2x+2y+1
(x-y)²-2x+2y+1=(x-y)²-2(x-y)+1
=(x-y-1)²