The line x = a is a vertical asymptote of the graph of y = f (x) if one or more of
the following holds:
The graph of (Figure N2–4) has x = 0 (the y-axis) as the vertical
asymptote.
The graph of (Figure N2–5) has x = 1 as the vertical asymptote.
The graph of (Figure N2–6) has the line x = 2 as the vertical
asymptote.
Example 8 __
From the graph of in Figure N2–7, describe the asymptotes of k
using limits.
Figure N2–7
SOLUTION: We see that y = 2 is a horizontal asymptote, since
Also, x = 3 is a vertical asymptote; the graph shows that