（X-1）分之1-（X+1）分之1-（X²+1)分之2－（X的4次方＋1）分之4
问题描述：
（X-1）分之1-（X+1）分之1-（X²+1)分之2－（X的4次方＋1）分之4
答
1/(x-1) - 1/(x+1)-2/(x^2+1)- 4/(x^4 +1)=[(x+1)-(x-1)] /[ (x-1)(x+1)] -2/(x^2+1)- 4/(x^4 +1)=2/(x^2-1)-2/(x^2+1)- 4/(x^4 +1)=[2(x^2+1)-2(x^2-1)] / [(x^2-1)(x^2+1)]- 4/(x^4 +1)=4/(x^4-1)- 4/(x^4 +1)=[...