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