Question

xy(x+y)的2次方-4x的3次方乘y的3次方是多少

Answer 1

xy(x+y)²-4x³y³
=xy[(x+y)²-(2xy)²]
=xy(x+y+2xy)(x+y-2xy)

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Answer 2

xy(x+y)^2-4x^3y^3
=xy(x+y)^2-xy*(4x^2y^2)
=xy[(x+y)^2-(4x^2y^2)]
=xy(x+y-2xy)(x+y+2xy)