This post serves as a cheat sheet for differentiation. It just includes the most basic of the rules to be remembered when computing derivatives. First a little reminder on the notation being used in differentiation. Leibniz’s notation for the first derivative of a function f(x) is Newton’s notation for the first derivative of a […]

## On critical points of functions

There is a really large number of applications in engineering, in which the identification of critical points (maxima and minima) of a function is crucial for the analysis and modeling of a process or a system. Generally, one may identify three kinds of critical points, that is (a) maxima, (b) minima and (c) saddle […]

## A short note on functionals, conserva...

The thing starts with invariance, conservation and symmetry… Invariant is something that is unchanged by a coordinate transformation. Conserved is something that is unchanged by a process within a given coordinate system. Symmetry could be considered a broader property of some ‘universe’ in which some entity of interest remains the same under a specific […]