The subject of perturbation expansions is a powerful analytical technique which can be applied to problems which are too complex to have an exact solution - for example, calculating the drag of an aircraft in flight. These techniques can be used in place of complicated numerical solutions. In some areas such as boundary layers it provides the essential ideas of scaling of regions of rapid change which must be understood before an appropriate discretization can be constructed. The book is aimed at students in applied mathematics, engineering, industrial mathematics, fluid mechanics and...