4 2 x - 8*x - 9
x^4 - 8*x^2 - 9
(x + 3)*(x - 3)*(x + I)*(x - I)
(((x + 3)*(x - 3))*(x + i))*(x - i)
4 2 -9 + x - 8*x
-9 + x^4 - 8*x^2
-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)