已知x²+2xy+y²-x-y+1/4=0
问题描述:
已知x²+2xy+y²-x-y+1/4=0
求x+y+2013的值(忘打了)
答
(x+y)²-(x+y)+(1/4)=0
(x+y-1/2)²=0
x+y=1/2
x+y+2013
=1/2+2013
=2013.5