x + 1 ------------- 3 2 x + x - 2*x
1 + x ------------- 2 3 x + x - 2*x
(1.0 + x)/(x^2 + x^3 - 2.0*x)
1 + x ------------------ x*(-2 + x*(1 + x))
1 + x --------------- / 2\ x*\-2 + x + x /
1 + x ------------------ x*(-1 + x)*(2 + x)