先化简,再求值:(4)4xy-[(x²+5xy-y²)-(x²+3xy-2y²)
先化简,再求值:{xy(x²-3y)+3xy²}(-2xy)+x³y²(2x-y
先化简,再求值 4(xy²+3xy-2x²y)-[12xy-3(3x²y-2xy²
化简求值 已知:(x+2)2;+|y+1|=0求5xy²-{2xy²-[3xy²(4xy&
(1)先化简,再求值:[4(xy-1)²-(xy+2)(2-xy)]÷1/4xy,其中x=-2,y=1/5.
化简求值:【4(xy-1)²-(xy+2)(2-xy)】÷¼xy,其中x=-3,y=1/5
先化简,再求值:4x²y-【6xy-2(4xy-2)-xy²】+1.其中x=-二分之一,y=2.
先化简,再求值.x²y²-4)(-x²y²-4)-4(xy-1/2)·(xy-1
化简并求值 xy-2{xy-[3x²y-(xy²+0.5xy)]+4x²y},其中x=1,
先化简,再求值 ⒈2(Xy+Xy)-3(Xy-xy)-4Xy,其中X=1,y=-1
-3【y-(3x²-3xy)】-【y+2(4x²-4xy)】,其中=3,y=3分之1.先化简,再求值
-3(xy-2x²)-[y²-(5xy-4x²)+2xy]
3x²y+xy²-[2xy²-4x²y+(x²y-2xy²)