f(x) = a_5x^5 + a_4x^4 + a_3x^3 + a_2x^2 + a_1x + a_0

a_0 = 4.2 (slider from -10 to 10, step 0.01)
a_1 = -0.25 (slider from -1 to 1, step 0.0001)
a_2 = -0.23 (slider from -1 to 1, step 0.0001)
a_3 = -0.41 (slider from -1 to 1, step 0.0001)
a_4 = -0.38 (slider from -1 to 1, step 0.0001)
a_5 = 0.28 (slider from -1 to 1, step 0.0001)
f(x) = (a_5 * x^(5)) + (a_4 * x^(4)) + (a_3 * x^(3)) + (a_2 * x^(2)) + (a_1 * x) + a_0
f0(x) = ((-(1 / 500)) * x^(3)) - (2 / 125 * x^(2)) + (77 / 100 * x) + 156 / 25
h0(x) = (-0.002 * x^(3)) - (0.016 * x^(2)) + (0.77 * x) + 6.24