3 x + 2*x
x^3 + 2*x
/ 2\ x*\2 + x /
x*(2 + x^2)
/ ___\ / ___\ x*\x + I*\/ 2 /*\x - I*\/ 2 /
(x*(x + i*sqrt(2)))*(x - i*sqrt(2))
x^3 + 2.0*x