ABSTRACT
Logarithmic differentiation is a means of differentiating algebraically complicated functions or functions for which the ordinary rules of differentiation do not apply. Logarithmic differentiation relies on the function of a function rule (i.e. chain rule) as well as properties of logarithms (in particular, the natural logarithm or logarithm to the base e) to transform products into sums and divisions into subtractions, and can also be applied to functions raised to the power of variables of functions. With certain functions containing more complicated products and quotients, differentiation is often made easier if the logarithm of the function is taken before differentiating. Whenever an expression to be differentiated contains a term raised to a power which is itself a function of the variable, then logarithmic differentiation must be used. Logarithmic differentiation occurs often enough in engineering calculations to make it an important technique.
