Question

初一数学因式分解

x^3-x+y^3-y

Answer 1

x^3-x+y^3-y
=(x+y)(x^2-xy+y^2)-(x+y)
=(x+y)(x^2-xy+y^2-1)

Answer 2

（x+y)^3=x^3+y^3+3xy^2+3yx^2
所以原式=（x+y)^3-3xy^2-3yx^2-x-y
=(x+y)(x^2+y^2-xy-1)