化简 1.x-2(x+2y)+3(2y-x) 2.-3(xy-2x的平方)-[y的平方-(5xy-4x的平方)+2xy]

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化简 1.x-2(x+2y)+3(2y-x) 2.-3(xy-2x的平方)-[y的平方-(5xy-4x的平方)+2xy]

化简 1.x-2(x+2y)+3(2y-x) 2.-3(xy-2x的平方)-[y的平方-(5xy-4x的平方)+2xy]
化简 1.x-2(x+2y)+3(2y-x) 2.-3(xy-2x的平方)-[y的平方-(5xy-4x的平方)+2xy]

化简 1.x-2(x+2y)+3(2y-x) 2.-3(xy-2x的平方)-[y的平方-(5xy-4x的平方)+2xy]
1.x-2(x+2y)+3(2y-x)=-4x+10y
2.-3(xy-2x的平方)-[y的平方-(5xy-4x的平方)+2xy]=6x^2-y^2-4xy

1. x-2(x+2y)+3(2y-x)
=x-2x-4y+6y-3x
=-4x+2y
2.-3(xy-2x^2)-[y^2-(5xy-4x^2)+2xy]
=-3xy+6x^2-y^2+5xy-4x^2-2xy
=2x^2-y^2