26 D CHAPTER 5
5.18
h(x) = x + 3 for x = 3, the graph (Fig. 5-18) is the straight line y = x + 3. The range is the set of all real
numbers.
Fig. 5-18
5.20
5.21
5.22
The domain is the set of all real numbers. The graph (Fig. 5-19) is the reflection in the line y = x of the
graph of y = x*. [See Problem 5.100.] The range is the set of all real numbers.
Is Fig. 5-20 the graph of a function?
Since (0,0) and (0,2) are on the graph, this cannot be the graph of a function.
Is Fig. 5-21 the graph of a function?
Since some vertical lines cut the graph in more than one point, this cannot be the graph of a function.
Is Fig. 5-22 the graph of a function?
Since each vertical line cuts the graph in at most one point, this is the graph of a function.
Fig. 5-22
Fig. 5-19
Fig. 5-20
Fig. 5-21
I The domain is the set of all real numbers. Since
for
and
5.19
if
if