化简(x³-1/x²+x+1)+(x³+1/x+1)-(x³-x/x-1)

化简(x³-1/x²+x+1)+(x³+1/x+1)-(x³-x/x-1)
化简(x³-1/x²+x+1)+(x³+1/x+1)-(x³-x/x-1)

化简(x³-1/x²+x+1)+(x³+1/x+1)-(x³-x/x-1)
已知
(x³-1)/(x²+x+1)=(x-1)
(x³+1)/(x+1)=(x²-x+1)
(x³-x)/(x-1)=(x(x²-1)/x-1)=x²+x
所以,
(x³-1)/(x²+x+1)+(x³+1)/(x+1)-(x³-x)/(x-1)
=(x-1)+(x²-x+1)+x²+x
=2x²+x

同志，题目写清楚，是(x³-1)/(x²+X+1)+(x³+1)/(X+1)-(x³-x)/(X-1)还是就是你题目上写的。