已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y+1)+1-2y】的值,

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已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y+1)+1-2y】的值,已知x²+y²+5=2x+4y,求【

已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y+1)+1-2y】的值,
已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y+1)+1-2y】的值,

已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y+1)+1-2y】的值,
1 , -3

x²+y²+5=2x+4y ∴(x-1)²+(y-2)²=0 ∴x=1,y=2
2x²-(x-y)(x-y)=2x²-(x²+y²-2xy)=x²-y²+2xy=1-4=4=1
(x+y-1)(x-y+1)+1-2y=X²-Y²=1-4=-3