5. Repeat Problem 4 employing two iterations of the parabolic interpolation optimization

method. Choose the initial set of three interpolation points: x1=0.4, x2=0.6 and x3=0.7.

Plot the interpolating parabola (after the first iteration) along with f(x), on the same graph,

over x-axis range [0.3 0.8]. You may use the interp2_mh script.