Often in Physics or Engineering it is necessary to use a calculus operation known as differentiation. Unlike textbook mathematics, the differentiated functions are data generated by an experiment or a computer code.
Begin with the Taylor series as seen in Equation 1.
Next by cutting off the Taylor series after the fourth term and evaluating it at h and -h yields Equations (2) and (3).
Then by subtracting Equation (2) by Equation (3) yields.