x - 1 ---------- 2 x - x - 1
(x - 1)/(x^2 - x - 1)
(-1 + x)/(-1 + x^2 - x)
-1 + x ----------- 2 -1 + x - x
1 - x ---------- 2 1 + x - x
(1 - x)/(1 + x - x^2)
(-1.0 + x)/(-1.0 + x^2 - x)
-1 + x --------------- -1 + x*(-1 + x)
(-1 + x)/(-1 + x*(-1 + x))