[2/(x+1)]^3-x^3+5[2/(x+1)-x]>0
[2/(x+1)-x]*[4/(x+1)^2+4x/(x+1)+x^2+5]>0
[2/(x+1)-x]*[(2/(x+1)+x/2)^2+7x^2/4+5]>0
2/(x+1)-x>0
(x-1)(x+2)/(x+1)
解不等式:8/(x+1)^3+10/(x+1)-x^3-5x>0
[2/(x+1)]^3-x^3+5[2/(x+1)-x]>0
[2/(x+1)-x]*[4/(x+1)^2+4x/(x+1)+x^2+5]>0
[2/(x+1)-x]*[(2/(x+1)+x/2)^2+7x^2/4+5]>0
2/(x+1)-x>0
(x-1)(x+2)/(x+1)