若xˆ2 •Yˆ3﹤0,化简-2xy •|(-1/2)•x
1、(-7x^y)(2x^y-3xy^3+xy) 2、((x-y)^6)/((y-x)^3)/(x-y)
若x+y-5xy=0,求(2x-3xy+2y)/(x+2xy+y)的值
若x-y=4,xy=1,求(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值
计算3xy[2xy-x(y-2)+x-1]
先化简再求值3(xˆ2y-2xy+x)-2(2x+5xˆ2y-xyˆ2).其中x=-1,y
化简!1、(x^2-xy)+xy+y^2 2、3(x^2-xy)-xy+y^2
化简:x-y/x+3y÷x^-y^2/x^2+6xy+9y^2-(xy/x+y)
若(3xy+2)+|7-x-y|=0,求代数式(5xy+10y)-[-5x-(4xy-2y+3x)]的值.
已知x²-3xy+4x=3,y²+xy-4y+7=0,则xy-1/2(x²+y²
xy/3x+2y=1/8 xy/2x+3y=1/7
若x,y满足x^+2y^-2xy+1=0,求xy的值
若两个正实数x,y满足x^2+2xy-3y^2=0,求x^2+xy+y^2/x^2-xy+y^2