已知lx+2y+1l+(-y-2)^2=0,求(2x-y)^2-2(2x-y)(x+2y)+(x+2y)^2的值

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已知lx+2y+1l+(-y-2)^2=0,求(2x-y)^2-2(2x-y)(x+2y)+(x+2y)^2的值已知lx+2y+1l+(-y-2)^2=0,求(2x-y)^2-2(2x-y)(x+2y

已知lx+2y+1l+(-y-2)^2=0,求(2x-y)^2-2(2x-y)(x+2y)+(x+2y)^2的值
已知lx+2y+1l+(-y-2)^2=0,求(2x-y)^2-2(2x-y)(x+2y)+(x+2y)^2的值

已知lx+2y+1l+(-y-2)^2=0,求(2x-y)^2-2(2x-y)(x+2y)+(x+2y)^2的值
x+2y+1=0
y+2=0 得y=-2,x=3
代入原式:(2x-y)^2-2(2x-y)(x+2y)+(x+2y)^2
先化简 =(2x-y-x-2y)^2
=(x-3y)^2
=(3+6)^2=81