Finite difference - Wikipedia
https://en.wikipedia.org/wiki/Finite_differenceIn an analogous way, one can obtain finite difference approximations to higher order derivatives and differential operators. For example, by using the above central difference formula for f ′(x + h/2) and f ′(x − h/2) and applying a central difference formula for the derivative of f ′ at x, we obtain the central difference approximation of the second derivative of f: Second-order central
Numerical differentiation: finite differences
www.dam.brown.edu › people › alcyewis called the first-order or O(∆x) backward difference approximation of f0(x). By combining different Taylor series expansions, we can obtain approximations of f0(x) of various orders. For instance, subtracting the two expansions f(x+∆x) = f(x)+∆xf0(x)+∆x2 f00(x) 2! +∆x3 f000(ξ 1) 3!, ξ 1 ∈ (x, x+∆x) f(x−∆x) = f(x)−∆xf0(x)+∆x2
Backward differentiation formula - Wikipedia
https://en.wikipedia.org/wiki/Backward_differentiation_formulaThe backward differentiation formula (BDF) is a family of implicit methods for the numerical integration of ordinary differential equations. They are linear multistep methods that, for a given function and time, approximate the derivative of that function using information from already computed time points, thereby increasing the accuracy of the approximation. These methods are especially used for the solution of stiff differential equations. The methods were first introduced …