计算:(x^2y)^2*(-3xy^3)*(-6x^2y^4)
计算:3xy[2xy-x(y-2)+x]
计算4xy+(x-2y)的平方+(x+3y)(3y-x)
计算 2xy[4x²y²-3y(xy+x²y)-xy²]
计算(3x^3y-x^2y+1/2xy)÷(-1/2xy)
计算:(-7x²y)(2x²y-3xy³+xy)
计算3x/8y×16y²/27x² (2xy-x²)÷x-2y/xy 2x-6/x
(2X平方y+3xy平方)-(6x平方-3XY平方)(计算)
计算(1)3x/8y×16y²/27x² (2)(2xy-x²)÷x-2y/xy 2x-6
计算(1)x/x+y-x/x-y (2)a+2+4/a+2 (3)x^2-y^2/xy÷(x+y)
计算(2x^3-3x^2y-2xy^2)-(x^3-2xy^2+y^3)+(3x^3y-x^3-y^3
已知;x+y=4,x-y的绝对值=6,求xy(y的平方+y)-y的平方(xy+2x)-3xy
1.计算 (-x方+2xy-y方)-2(xy-3x方)+3(2y方-xy)