X ( k ) x ( n )en 0
N 1
j
2 nk N
N 1 kn X(k)= x (n) WN=n=0
n=0
1
2 j kn 4 e
= 1+e
j
2
k
X(0)= 1+1=2 j X(1)= 1+e 2=1 j= 2 e j /4
X(2)= 1+e j =1 1=03 j X(3)= 1+e 2=1+j= 2 ej /4
X ( k ) x ( n )en 0
N 1
j
2 nk N
N 1 kn X(k)= x (n) WN=n=0
n=0
1
2 j kn 4 e
= 1+e
j
2
k
X(0)= 1+1=2 j X(1)= 1+e 2=1 j= 2 e j /4
X(2)= 1+e j =1 1=03 j X(3)= 1+e 2=1+j= 2 ej /4
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