2
.
x
i
′
(
t
)
x
i
(
t
)
(
-
x
i
-
2
(
t
)
-
x
i
(
t
)
-
x
i
+
1
(
t
)
+
1
)
x
i
(
0
)
=
0
.
4
+
0
.
3
sin
2
π
i
N
N
38
t
388
.
view
{
x
1
,
x
2
}
all
x
i
'
s
