x*（9x^3y-3xy^2）÷（-3x^2y）= 【（x+y）^2-（x-y）^2】÷（-4xy）=

化简：x-y/x+3y÷x^-y^2/x^2+6xy+9y^2-(xy/x+y) 【x(xy-xy)-y(x-xy)】÷3xy (x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y)答案应为-2x-x*x-3x， 几道数学题：x-x^2分之x^2-1×1-y分之xy-x,（xy-x^2）÷xy分之x-y,x^2+x分之x-3÷（x^2-6x+9）谢谢! ①(x²-6x+6)/(x²-1)▪(x²+x)/(x-3)②（xy-x²）÷(x-y)/xy③[(x²-y²)/y]²÷(x²+xy)³▪[xy/(y-x)]²④[(x²+2x-3)/(9-x²)]³▪[-(x-3)/(1-x)]² 计算：3xy[2xy-x（y-2）+x] 计算：1.（x-1)^2+2(1-x) 2.(x-y)/(x+3y)÷(x^2-y^2)/(x^2+6xy+9y^2)-2y/(x+y）1.（x-1)^2+2(1-x)2.(x-y)/(x+3y)÷(x^2-y^2)/(x^2+6xy+9y^2)-2y/(x+y） 因式分解(xy-x^2)^3-x^3（y-x） (3xy)^2÷(-xy)+(x-2y)^2-(x+2y)(x-2y) （x*x-2xy）*9x*x-(9xy*y*y-12x*x*x*x*y*y)/3xy,其中x=1,y=-1 化简 帮个忙, 计算或化简：[（x-y）/(x+3y)]÷[（x²-y²）/(x²+6xy+9y²)]-（2y）/x+y -x-3xy+y x²/xy-x/y 3x/4x+y - x-2y/4x+y (1-y/y+x)÷x/y²-x² 因式分解:12xy^2(y-x)+xy^3(x-y)+4x^2y(x-y) 计算：3xy(x²y-xy²+xy)-xy²(2x-xy+2x） 计算(3x^3y-x^2y+1/2xy)÷(-1/2xy） x^2y-x^3/x^2+2xy+y^2÷x/x-y乘以x+y/x^2-2xy+y^2 -xy^2(x+y)^3+x(x+y)^2因式分解