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