This method is used to derive derivative of a numerical function f(x) using newton's forward difference formula.
Derivatives Using Newton’s Forward Difference Formula :
Consider the data (xi, f(xi)) given at equispaced points xi = x0 ih, i = 0, 1, 2, ..., n where h is the step length. The Newton’s forward difference formula is given by
....................1.1
Set x = x0 sh. Now, (1.1) becomes
.....................1.2
Note that,
The magnitudes of the successive terms on the right hand side become smaller and smaller.
Differentiating (1.2) with respect to x, we get
....................1.3
At x = x0, that is, at s = 0, we obtain the approximation to the derivative f ′(x) as
............................1.4
Differentiating (1.3) with respect to x, we get
......................1.5