(-1/2x^3y^2)*(4y+8xy^3)

计算：（1）8x^2y^2*(-3x/4y^5) (2)(x+y)^2/xy-y^2*(y-x)^2/xy+y^2 化简：3x^2-[5xy-(x^y-3xy)+4x^2y-8xy] XY(XY+3)+(XY+4)+4(X+Y+1)-(X+Y+2) 因式分解:12xy^2(y-x)+xy^3(x-y)+4x^2y(x-y) (x+y)(x+y+2xy)+(xy+1)(xy-1)(x+y)(x-y)+4(y-1) x²-y²+5x+3y+4（x+y-2xy)(x+y-z)+(xy-1）² 诺x+y=6,xy=4 求(5x-4y-3xy)-(8x-y+2xy) 7x^2y-[xy+4(xy^2+1/8xy)-3x^2y]答对给分 若x-y=4,xy=1,求(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值 (-2xy+2x+5y)-(3xy+2y-2x)-(x+4y+xy)其中x-y=4xy=-1 若x-y=4,xy=1,则(2x+y-2xy)-(3x+2y+xy)-(4xy+3y-5x)= x-y=1,xy=2.求：(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值 .已知:x-y=1,xy=-2.求:(-2xy+2 x+3y)-(3xy+2y-2x)-(x+4y+xy)的值 若（x+1)^2+|y-2|=0,求3x^2-[5xy-(x^2y-3xy)+4x^2y-8xy]的值 化简求值x-4y/2x-7xy+3y×x-2xy-3y/2x+3xy-2y÷3x-6y/4x-4xy+y,其中：x=1999,y=-1 x²/xy-x/y 3x/4x+y - x-2y/4x+y (1-y/y+x)÷x/y²-x² 4xy-[(x²+5xy-y²)-(3xy-1/2y)]x=3,y=-6 若x+y=-1,则x^4+5x^3y+x^2y+8x^2y^2+xy^2+5xy^3+y^4=( )若x+y=-1,则x^4+5x^3y+x^2y+8x^2y^2+xy^2+5xy^3+y^4=( ）