In this example the function is the rule that says ‘to each number x in the
interval /p0/x0/3p /4, associate a number y obtained by first finding sin x and then adding the result to unity’. The interval /p0/x0/3p /4 is called the domain of definition (domain for short) of the function, and the interval
00/y0/2 over which y ranges for all x in the domain is called the range of the function. The graph of this function, together with its domain and range, is
shown in Fig. 4.