已知5x^2-4xy+y^2-2x+1=0,(x-y)^2006=?
问题描述:
已知5x^2-4xy+y^2-2x+1=0,(x-y)^2006=?
答
5x^2-4xy+y^2-2x+1=0
4x^2 - 4xy + y^2 + x^2 - 2x + 1 = 0
(2x - y)^2 + (x-1)^2 = 0
所以
x = 1
y = 2x = 2
(x-y)^2006 = 1