function a = plot_f_and_f_prime()
    xs = 1:100;
    f_ys = [];
    f_prime_ys = [];
    for i = xs
        f_ys = [f_ys, f(i)];
        f_prime_ys = [f_prime_ys, f_prime_two(i)];
    end
    plot(xs, f_ys)
    hold all
    plot(xs, f_prime_ys)
end