x
0
0
.
1
zoom
0
.
4
dx
0
.
3
d
y
=
y
'
d
x
Δ
y
=
f
(
x
+
Δ
x
)
-
f
(
x
)
dx
=
Δ
x
-
0
.
5
0
.
5
-
0
.
5
0
.
5
f
(
x
)
