2 3*x + x - 1
3*x^2 + x - 1
/ ____\ / ____\ | 1 \/ 13 | | 1 \/ 13 | |x + - - ------|*|x + - + ------| \ 6 6 / \ 6 6 /
(x + 1/6 - sqrt(13)/6)*(x + 1/6 + sqrt(13)/6)
2 -1 + x + 3*x
-1 + x + 3*x^2
-1.0 + x + 3.0*x^2
-1 + x*(1 + 3*x)