第2章
221
1
21
01
xt2
2
21
x1t
3
x2t1
21
1
2
t
1
011
2
t
15
1005t1
4
21
xt21
5
21
xtht
2
01
1
2
4
6
t
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1
2
3
t
6
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2
1
7
21
8
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12
3
t
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2
t
x
2
10
1
2
t
2
1
1
2
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05
05

4
1
1
6
3
3
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1
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3
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2
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2
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x


1
x2

05
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6
9
4
2
0
2
4
6


8
1
x
12
2my
2m0
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mx
21
2y
0
2m1
05
101
3
5
7


4
2012
2
4
6
8


10
25
x
h
2112304115
1
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x
h

4
2
32
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12
1
x

13

1
Δx

x
2
x
1
4

3
1
0
1
1
05
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101
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f2
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h

信号与系统
214
15
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1
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11
05

05
2
16

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0123
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17

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23
1
2t1eutt
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1
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512
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2
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2
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1
1
01234
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10
1
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05
7
1
sg
si
πt
t
8
101
210
121
3
1
t
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1
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5πtutut2
21
t
10

u
5u
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1
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1
12
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u
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11
12
050250125
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1

2
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1
0
k
1
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u
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3

3k
13k
11
0
2
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76

14
16


1
3
24
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πtut2si
πt1ut1si
πt2ut2d
but1utut1ut2
si
πt2kut2ksi
πt12kut12k
k0

word文档可自由复制编辑
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