化简求值:x-y/x²-2xy+y²-xy+y²/x²-y²,其中(x
化简求值:x-y/x²-2xy+y²-xy+y²/x²-y²,其中(x
化简求值(x+y)(x-y)-(x-y)²-6x²y/2y+(2xy)²/(-4xy)其中
化简求值(x+y)(x-y)-(x-y)²-6x²y除2y+(2xy)²除(-4xy)其中
化简求值3x²y-[2xy-2(xy-3/2x²y)+xy]+3xy²其中x=3、y=-1
化简求值(xy-x²)/xy分之x²-2xy+y²乘x²分之x-y,其中y=二分
化简求值:(2x²y-2xy²)-【(-3x²y²+3x²y)】,其中
化简求值:(x+y)(x-y)+(x-y)²-(6x²y-2xy²)÷2y,其中x=-2,
化简求值:(-1/3XY)²[xy(2x-y)-2x(xy-y²)],其中X=-3/2,Y=-2
化简求值:(负三分之一 xy)²[xy(2x-y)-2x(xy-y²)],其中x=-一又二分之一,y
化简并求值 xy-2{xy-[3x²y-(xy²+0.5xy)]+4x²y},其中x=1,
化简求值 3x²y-[2xy-2(xy-2/3x²y)]+x²y²,其中x=3,
先化简在求值(x+y)²-(x-y)(x+y)-(xy)²÷(xy),其中x,y是方程组『3x+2y