(*						      *)
(* Numerical Mathematics and Computing, Fifth Edition *)
(* Ward Cheney & David Kincaid		              *)
(* Brooks/Cole Publ. Co.			      *)
(* (c) 2003                                           *)
(* No warranties implied or expressed.	              *)
(* File: newt_interp1				      *)

(* Newton interpolation polynomial *) 

InterpolatingPolynomial[{{0,-5}, {1,-3}, 
                        {-1,-15}, {2,39}, {-2,-9}}, x]
Simplify[%]
%% /. x -> 1/2