a10 = 1
a11 = 0.35
b1 = 0.0175
c1 = 0.01
a20 = 0.14
a21 = 0.075
b2 = 0.015
a1(x) = a10 + (a11 * sin((π * x / 6)))
a2(x) = a20 - (a21 * sin((π * x / 6)))
f(x, y, z) = (y * (a1(x) - ((b1 - c1) * z) - (c1 * (y + z))))
g(x, y, z) = (z * ((-a2(x)) + (b2 * y)))
y0 = 0.5
z0 = 0.5
numeriskIntegral1, numeriskIntegral2 = NSolveODE({f, g}, 0, {y0, z0}, 50)