x-y=1,xy=2,求x^3y-2x^2y^2+xy^3的值

x-y=1,xy=2,求x^3y-2x^2y^2+xy^3的值
x-y=1,xy=2,求x^3y-2x^2y^2+xy^3的值

x-y=1,xy=2,求x^3y-2x^2y^2+xy^3的值
整理原式x^3y-2x^2y^2+xy^3=xy(x²-2xy+y²)=xy(x-y)²
则原式=2*1²=2

x-y=1,xy=2,则x^3y-2x^2y^2+xy^3=xy(x²-2xy+y²)=xy(x-y)²=2×1²=2

x=2 y=1 你那个尖号是啥意思

原式=（X-Y）(X^2-2XY+Y^2)
=1乘(1)^2
等于1

x^3y-2x^2y^2+xy^3
=xy(x^2-2xy+y^2)
=xy(x-y)^2
因：x-y=1,xy=2
所以：原式=2x1^=2

x-y=1,xy=2
则x=2,y=1
x^3y-2x^2y^2+xy^3
=8-8+2=2