f(x) = x·(x3 + 9·x2 + 15·x - 25)·(-0.5) = -0.5·x4 - 4.5·x3 - 7.5·x2 + 12.5·x
f(-x) = -0.5·(-x)4 - 4.5·(-x)3 - 7.5·(-x)2 + 12.5·(-x)
f(-x) = -0.5·x4 + 4.5·x3 - 7.5·x2 - 12.5·x ≠ f(x)
f(-x) = -(0.5·x4 - 4.5·x3 + 7.5·x2 + 12.5·x) ≠ -f(x)
Also weder punktsymmetrisch zum Ursprung noch achsensymmetrisch zur y-Achse.