化简求值y/(x-y)+y³/(x³-2x²y+xy²)÷(xy+y²
化简求值:x-y/x²-2xy+y²-xy+y²/x²-y²,其中(x
先化简,再求值:{xy(x²-3y)+3xy²}(-2xy)+x³y²(2x-y
1.化简求值:(x+y)(x-y)-(x-y)²-6x²y÷2y+(2xy)²÷(-4xy
化简求值.(x-2y分之4xy 再加+x)除以4x³-x²y分之x²+4xy+4y
化简求值:(x+y)(x-y)+(x-y)²-(6x²y-2xy²)÷2y,其中x=-2,
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[1-(2x/x+y)]÷ (x²-2xy+y²/3x+3y)+(x²+xy/x&
[-xy/(x-y)²]²×(y²-xy/x)³
化简求值3x²y-[2xy-2(xy-3/2x²y)+xy]+3xy²其中x=3、y=-1
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
先化简,后求值[(x-y)²-(x+y)]/(2xy) 先化简,后求值[(x-y)²-(x+y)]/