ABSTRACT
This chapter defines base, power, exponent, index and logarithm. It distinguishes between common and Napierian (i.e. hyperbolic or natural) logarithms and evaluates logarithms to any base. The chapter states the laws of logarithms, simplifies logarithmic expressions, and solves equations involving logarithms. It solves indicial equations and sketches graphs of log10x and logex. The Richter scale which measures earthquake intensity is a logarithmic scale. Biomedical engineers use logarithms to measure cell decay and growth, and also to measure light intensity for bone mineral density measurements. Logarithms are especially useful when dealing with the graphical analysis of non-linear relationships and logarithmic scales are used to linearise data to make data analysis simpler.
