% initial point x0
x0 = -.5;
x1 = x0 - f(x0)/df(x0);
ep = 10^-6;            % the error tolerance
max_iterate = 10^4;    % the maximum of the iteration steps

it_count=1;            %it_count is the iteration steps, starting with 1

while ( error >= ep && it_count < max_iterate )
    it_count = it_count + 1;
    x0 = x1;
    x1 = x0 - f(x0)/df(x0);
end

it_count
format long e
root1 = x1

clear all

% initial point x0
x0 = .5;
x1 = x0 - f(x0)/df(x0);
ep = 10^-8;            % the error tolerance
max_iterate = 10^4;    % the maximum of the iteration steps

it_count=1;            %it_count is the iteration steps, starting with 1

while ( abs(x1-x0) >= ep && it_count < max_iterate )
    it_count = it_count + 1;
    x0 = x1;
    x1 = x0 - f(x0)/df(x0);
end

it_count
format long e
root2 = x1