4 2 - x + 8*x + 9
-x^4 + 8*x^2 + 9
4 2 9 - x + 8*x
9 - x^4 + 8*x^2
(x + 3)*(x - 3)*(x + I)*(x - I)
(((x + 3)*(x - 3))*(x + i))*(x - i)
9.0 - x^4 + 8.0*x^2
/ 2\ -\1 + x /*(-3 + x)*(3 + x)
-(1 + x^2)*(-3 + x)*(3 + x)
2 / 2\ 9 + x *\8 - x /
9 + x^2*(8 - x^2)