Functions of Several Variables

InChapter 1 we studied planes, which are the simplest surfaces in R³. A plane is represented in terms of two parameters, see e.g.(1.31). Other surfaces in R³ can also be represented using two parameters, i.e. these surfaces are graphs z = f (x, y),i.e. functions of two variables (x, y). Such functions, and surfaces, are studied in this section.