Explore Numerical Computations

    We can use the forward difference formula for numerical differentiation and get a more accurate approximation.

        

Note.  In this case the approximation is exact and the error is zero.  This is because is a polynomial of degree less than 3.  

Aside.  If we want to use a function for which the numerical approximation is not exact, then    will suffice.

(c) 2006 John H. Mathews, Russell W. Howell