4 2 x + 8*x - 40
x^4 + 8*x^2 - 40 при x = 1
x^4 + 8*x^2 - 40
(1)^4 + 8*(1)^2 - 40
1^4 + 8*1^2 - 40
-31
-40.0 + x^4 + 8.0*x^2
2 / 2\ -40 + x *\8 + x /