/ 2 \ 2 x*\x + x/ - x - x - 1
x*(x^2 + x) - x^2 - x - 1 при x = 1/3
x*(x^2 + x) - x^2 - x - 1
(1/3)*((1/3)^2 + (1/3)) - (1/3)^2 - (1/3) - 1
((1/3)^2 + 1/3)/3 - (1/3)^2 - 1/3 - 1
-35/27
2 / 2\ -1 - x - x + x*\x + x /
-1.0 - x - x^2 + x*(x + x^2)
/ 2\ -1 + x*\-1 + x /
3 -1 + x - x
2 / 2 \ -1 - x - x + x*\x + x/