已知x-y=3,xy=10,则x²y-xy²=

已知x:y=3:2,求(x²+3xy)/(xy+2xy) 已知X/Y=2,则X²+2XY-3Y²/X²-XY+Y²=? 已知x-y=4xy，则2x+3xy-2yx-2xy-y 已知x/y=3,求(x²+2xy-3xy²)/(x²-xy+y²) 已知：X+Y=-3,XY=2,X²Y+XY² 已知x²-3xy+4x=3,y²+xy-4y+7=0,则xy-1/2(x²+y² 已知x+y=5,xy=3,x³+y³=(x+y)(x²-xy+y²),则1/x& 已知xy/x+y=1/2,则代数式3x-5xy+3y/-x+3xy-y= 已知x+y=4.x-y=6.求代数式xy(y²+y)-y²(xy+2x)-3xy的值 已知x/y=3,求x²+2xy-3y²/x²-xy+y² 已知y分之x=3,求x²-xy+y²分之x²+2xy-3y² 已知x/y=3,求x²+2xy-3y²/x²-xy+y²的值