How can I find the root of this equation?

I would like to create a function which finds the root of an equation numerically by using the following recursive formula:

x(n+1) = x(n) - ( f(x(n)) / g(x(n) ) , for n=1,2,3,...

where g(x(n)) = f( x(n) + f(x(n)) ) / f(x(n)).

This iterative procedure must stop when the absolute difference between x(n) and x(n+1) is less than a given tolerance epsilon. The function must accept as inputs, a scalar function 'f', an initial number 'x' and a positive number 'epsilon' to terminate the procedure. Hence by using this numerical technique I would like to find the root of the equation e^x-x^2=0.

function y=q3(x)
f=input('Enter a scalar function: ')
x=input('Enter a number: '); % initial number
epsilon=input('Enter a positive number: ')

Any help would be greatly appreciated. Thanks in advance.