1.(-2xy^2)*(3x^2y)^2 2.（-a)^2(2-3ab)

3a-3b/10ab*25a^b3/a^-b^= x^-4y^/x^+2xy+y^/x+2y/2x^+2xy 1.4x^2 y+3xy^2-x^2 y-3xy^2 -3 2.3(3a^2-2ab)-2(4b^2-ab) 3.2x- x²（x+y)(y-x)-xy(x+y)(x-y) 已知a+b=4,ab=-2,求多项式3a²b+3 1.x-z/xy - 2ab/xy (x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y) 初一因式分解和计算分利用乘法公式计算1.（a^2-ab-b^2)(a^2+ab-b^2)2.(x^2y+2xy^2)(3 合并下列同类项.xy^2-1/5xy^2-3x^2y+2x^2y+3xy^2-2xy^24a^2+3b^2+2ab-4a x^2-xy-6y^2+3xy+y+2 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 计算3xy[2xy-x(y-2)+x-1]