MA 3972-MA-Book May 8, 2018 13:46
76 STEP 4. Review the Knowledge You Need to Score High
The graph ofy= f(−x) is a reflection of the graph ofy=f(x) about they-axis. (See
Figure 5.4-16.)
x
y
y = f(−x) y = f(x)
−a 0 a
Figure 5.4-16
The graph ofy=−f(−x) is a reflection of the graph ofy= f(x) about the origin. (See
Figure 5.4-17.)
x
y
y = −f(−x)
y = f(x)
(a, b)
(−a, −b)
0
Figure 5.4-17
Stretching Graphs
Giveny= f(x), the graph ofy=af(x), wherea >1 is a vertical stretch of the graph
ofy= f(x), andy=af(x), where 0<a<1 is a vertical shrink of the graph ofy= f(x).
(See Figure 5.4-18.)
x
y
f(x)
af(x), 0 < a < 1
af(x), a > 1
0
Figure 5.4-18