2 x - 5*x + 3
x^2 - 5*x + 3
2 3 + x - 5*x
3 + x^2 - 5*x
/ ____\ / ____\ | 5 \/ 13 | | 5 \/ 13 | |x + - - + ------|*|x + - - - ------| \ 2 2 / \ 2 2 /
(x - 5/2 + sqrt(13)/2)*(x - 5/2 - sqrt(13)/2)
3 + x*(-5 + x)
3.0 + x^2 - 5.0*x