先化简,再求值:1/2x-2(x-1/3y^2)+3(-1/2x+1/9y^2)其中x.y满足(x-2)^2+丨y+3丨=0

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先化简,再求值:1/2x-2(x-1/3y^2)+3(-1/2x+1/9y^2)其中x.y满足(x-2)^2+丨y+3丨=0

先化简,再求值:1/2x-2(x-1/3y^2)+3(-1/2x+1/9y^2)其中x.y满足(x-2)^2+丨y+3丨=0
先化简,再求值:1/2x-2(x-1/3y^2)+3(-1/2x+1/9y^2)其中x.y满足(x-2)^2+丨y+3丨=0

先化简,再求值:1/2x-2(x-1/3y^2)+3(-1/2x+1/9y^2)其中x.y满足(x-2)^2+丨y+3丨=0
∵(x-2)^2+丨y+3丨=0
∴x=2,y=﹣3
∴1/2x-2(x-1/3y^2)+3(-1/2x+1/9y^2)
=1/2x-2x+2/3y²-3/2x+1/3y²
=﹙1/2-2-3/2﹚x+﹙2/3+1/3﹚y²
=﹣3x+y²
=﹣3×2+﹙﹣3﹚²
=﹣6+9
=3