2 2*x + 3*x + 1
2*x^2 + 3*x + 1
2 1 + 2*x + 3*x
1 + 2*x^2 + 3*x
(x + 1)*(x + 1/2)
1 + x*(3 + 2*x)
1.0 + 2.0*x^2 + 3.0*x
(1 + x)*(1 + 2*x)