2 x + 5*x + 1
x^2 + 5*x + 1
2 1 + x + 5*x
1 + x^2 + 5*x
/ ____\ / ____\ | 5 \/ 21 | | 5 \/ 21 | |x + - + ------|*|x + - - ------| \ 2 2 / \ 2 2 /
(x + 5/2 + sqrt(21)/2)*(x + 5/2 - sqrt(21)/2)
1.0 + x^2 + 5.0*x
1 + x*(5 + x)