3x^2-7x+2)/(2x^2+3x-2)=(x-2)*(3x-1)/(x+2)*(2x-1)
3x^2-7x+2=3*(x-2)*(x-1/3)=(x-2)*(3x-1)
2x^2+3x-2=2*(x+2)*(x-1/2)=(x+2)*(2x-1)
y=(x-2)*(3x-1)/(x+2)*(2x-1)
S(t) = -t^3/3 -7t^2 - 10t + 3
a(t) = S''(t) = -2t - 14
a(4) = -8 - 14 = -22 м/с^2
F = ma = -22 × 0,5 = -11 Н
lFl = 11 Н
Ответ : 11 Н (модуль)