d = 0.007 (slider from 0 to 0.1, step 0.001)
c = 0.25 (slider from 0 to 2, step 0.01)
a = 0.7 (slider from 0 to 5, step 0.05)
S'(t, S, I, R) = (((-a) * S) * I) + (d * R)
R'(t, S, I, R) = (c * I) - (d * R)
I'(t, S, I, R) = ((a * S) * I) - (c * I)
I0 = 0.0095 (slider from 0 to 0.1, step 1.0E-4)
R0 = 0 (slider from 0 to 1, step 0.001)
IntégraleNumérique1, IntégraleNumérique1_2, IntégraleNumérique1_3 = NSolveODE({S', I', R'}, 0, {1 - I0 - R0, I0, R0}, 2000)
b: c / a
f: y = c / a
g: y = ((d * (a - c))) / ((a * (d + c)))