计算:xy(x^-1+y^-1)
计算3xy[2xy-x(y-2)+x-1]
xy[(x^-1)+(y^-1)] 计算
计算:(5-xy/x^3-x^2y)/(1-5/xy)^2*(y-x)^3
计算(3x^3y-x^2y+1/2xy)÷(-1/2xy)
计算3x[xy-2x(1/y-x/3]+3y(x²-y²)
计算:1、(xy分之x²-y²)×(x-y分之x)-(y分之x);
xy-1+x-y
计算:(2分之1x^(2)y-2xy+y^(2))·3xy
计算:(x-2y)(1+x+2y+4y^2+2xy+x^2)
计算=(-3x²y)/(1/3xy²)
计算:(-3x^y)(1/3xy^2)=?
计算:(1).(-2xy²)*(3x²y)²