化简求值:[2x^2y^2-(xy+3)(xy-3)-9]/xy,其中x=2,y=-1/3
先化简,再求值 ⒈2(Xy+Xy)-3(Xy-xy)-4Xy,其中X=1,y=-1
化简求值3x²y-[2xy-2(xy-3/2x²y)+xy]+3xy²其中x=3、y=-1
化简并求值 xy-2{xy-[3x²y-(xy²+0.5xy)]+4x²y},其中x=1,
化简求值:(-1/3XY)²[xy(2x-y)-2x(xy-y²)],其中X=-3/2,Y=-2
(x+2y-3xy)-(-2x-y+xy),其中x+y=,xy=-,求值.
化简求值:[2x^2y^2-(xy+3)(xy-3)-9]/xy,其中x=2,y=-1/3
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:xy^3÷(-xy)+(x+2y)(x-2y),其中x=根号2,y=1
(3x-2y+3xy)-(x-4y-2xy),其中x+y=3 xy=-2 化简求值
化简求值3x-2y-5xy-(2x-3y+2xy),其中x+y=4,xy=-7
化简求值:根号x^-2xy+y^2 + x^2 -6xy+9y^2/x-3y,其中x=根号3,y=根号5
化简求值{(-1/2x^3y^4)^3+(-1/6xy^2)^2*3xy^2}/(-1/2xy^2)^3其中X=-2,y