[(-3xy)^2*x^3-2x^2*(3xy^2)^3*2/1y]/9x^4*y^2
(x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y)
计算3xy[2xy-x(y-2)+x-1]
(-3x^y+2xy)-( )=4x^+xy
1、(-7x^y)(2x^y-3xy^3+xy) 2、((x-y)^6)/((y-x)^3)/(x-y)
化简:x-y/x+3y÷x^-y^2/x^2+6xy+9y^2-(xy/x+y)
若x-y=4,xy=1,求(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值
已知:x-y=1,xy=-2.求:(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值
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
x^3y(-4y)^2+(-7xy)^2*(-xy)-5xy^3*(-3x)^2
已知x-y=4xy,则2x+3xy-2yx-2xy-y
xy(xy+1)+(xy+3)-2(x+y+2分之一)-(x+y-1)的平方