use newton raphson method to find roots of exp(-x)-x

clear all;

clc;

n = 11;

x = zeros(1,numel(n));

ea = zeros(1,numel(n));

g=@(x) exp(-x);

f=@(x) exp(-x)-x;

true_root=0.56714329;

disp('----------------------------------------------------');

disp('i xi Ea(%) Et(%) ');

disp('----------------------------------------------------');

for i=1:n-1

x(i+1)=g(x(i));

if x(i+1)~=0

ea(i+1)=100*abs(x(i+1)-x(i))/x(i+1);

end

end

e_t=100*abs(x-true_root)/true_root;

res=[[0:n-1]' x' ea' e_t'];

fprintf('%d %10.6f %10.3f %10.3f\n', res');

i use simple fixed-point iteration method. but i want to use newton raphson method. how can i this?