Definition of this basic method for approximating the derivative of a function with f'(x) ~ (f(x+d) - f(x)) / d.

Discussion of the potential problems with the first method for approximating derivatives.

Definition of this method, f '(x) ~ (f(x+d) - f(x-d)) / (2d), for approximating derivatives and its advantages over the previous method.

Improving upon the symmetric approximation for a derivative using extrapolation.