2
(1 + 3*x) - (-1 + x)*(9 + 9*x)
$$- \left(x - 1\right) \left(9 x + 9\right) + \left(3 x + 1\right)^{2}$$
(1.0 + 3.0*x)^2 - (9.0 + 9.0*x)*(-1.0 + x)
Рациональный знаменатель
[src] 2
(1 + 3*x) - (-1 + x)*(9 + 9*x)
$$- \left(x - 1\right) \left(9 x + 9\right) + \left(3 x + 1\right)^{2}$$
2
(1 + 3*x) - (-1 + x)*(9 + 9*x)
$$- \left(x - 1\right) \left(9 x + 9\right) + \left(3 x + 1\right)^{2}$$