1
第一章习题参考解?/p>
1.1
绘出下列函数波形草图?/p>
(1)
|
|
3
)
(
t
e
t
x
?/p>
?/p>
(2)
?/p>
?/p>
?/p>
?/p>
?/p>
?/p>
?/p>
?/p>
?/p>
?/p>
0
2
0
2
1
)
(
n
n
n
x
n
n
(3)
)
(
2
sin
)
(
t
t
t
x
?/p>
?/p>
?/p>
(4)
)
(
4
sin
)
(
n
n
n
x
?/p>
?/p>
?/p>
(5)
)]
4
(
)
(
[
4
cos
)
(
?/p>
?/p>
?/p>
?/p>
t
t
t
e
t
x
t
?/p>
?/p>
?/p>
(6)
)]
4
(
)
1
(
[
3
)
(
?/p>
?/p>
?/p>
?/p>
n
n
n
x
n
?/p>
?/p>
-2
0
2
4
6
8
10
-1
0
1
n
(4)
-2
-1
0
1
2
3
4
5
6
-1
0
1
t
(5)
-2
-1
0
1
2
3
4
5
6
7
8
0
20
40
60
80
100
n
(6)
-2
-1
0
1
2
0
1
2
3
t
(1)
-3
-2
-1
0
1
2
3
0
0.5
1
n
(2)
...
...
-1
0
1
2
-1
0
1
t
(3)