MATLAB - PLEASE HELP

(a) Write a Matlab program to compute an approximate value for the derivative of a function using the finite difference formula f) f(r+h)-f(x) h Test your program using the function tan(2) for r = 1. Plot the absolute error as a function of h for h = 10-4, k = 0,1,..., 16 on a log-log graph. Is the error minimized for a particular (optimal) value of h? Estimate the optimal h by differentiating the expression for the total computational error (truncation plus rounding), setting the result equal to zero and solving for h. Does it agree with the observed value? (b) Repeat the exercise using the central difference approximation f'(a) f(x+h)-f(x - h)