x*x + 13*x + 12 --------------- -2*x*x + x + 3
2 12 + x + 13*x -------------- 2 3 + x - 2*x
(12.0 + 13.0*x + x*x)/(3.0 + x - 2.0*x^2)
12 + x*(13 + x) --------------- 3 + x*(1 - 2*x)
-(12 + x) ---------- -3 + 2*x
1 27 - - - -------- 2 -6 + 4*x