x^(2n+3)-x^(2n+2)+x^(2n+1)

问题描述:

x^(2n+3)-x^(2n+2)+x^(2n+1)

x^(2n+3)-x^(2n+2)+x^(2n+1)
=x^(2n+1)*(x^2-x+1)