x^2+4xy+4y^2-2xy-2x-2y+8=x^2+2xy+4y^2-2x-2y+8=(x^2+2xy+y^2)+3y^2-2x-2y+8=(x+y)^2+3y^2-2(x+y)+1+7=[(x+y)^2-2(x+y)+1]+3y^2+7=[(x+y)-1]^2+3y^2+7最小值为7,所以同时满足y=0,x+y-1=03y^2=0 ∴y=0x+y-1=0 所以x=...