/ 2 \ (a + 3)*\a - 9/ ---------------- 2 a + 6*a + 9
(3.0 + a)*(-9.0 + a^2)/(9.0 + a^2 + 6.0*a)
/ 2\ \-9 + a /*(3 + a) ----------------- 9 + a*(6 + a)
-3 + a