Consider a discrete-time signal x[ n] defined byx[n] =1;

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Consider a discrete-time signal x[ n] defined by
x[n] = 1; – 2 ≤ n ≤ 2
2;|n| > 2

then y[n] = x[ 3n – 2] is equal to—

1. y[n] = 1; n = 0, 1
  – 1; otherwise
2. y[n] = 1; n = 1
  – 1; n = – 1
3. y[n] = 1; n = 0, 1
  0; otherwise
4. None of these

Correct Option: C

Given

x[n] =		1;	– 2 ≤ n ≤ 2
		0;	\|n\| > 2

Now, we have to determine
y[n] = x[3n – 2]
y[n] can be determined by applying two operation i.e., First shifting of sequence two unit right. Second scaling of sequence by a factor of 3.

y[n] = x[3n – 2] =		1;	n = 0, 1
		0;	otherwise

Hence, alternative (C) is the correct choice.