The DTFT of the given signal x[n] = u[n – 2] – u[n –

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The DTFT of the given signal
x[n] = u[n – 2] – u[n – 6]

1. e^2jΩ + e^3jΩ + e^4jΩ + e^5jΩ
2. e^{– 2jΩ} + e^{– 3jΩ} + e^{– 4jΩ} + e^{– 5jΩ}
3. e^{– 2jΩ} (1 – e^3jΩ)
  1 – e^jΩ
4. e^{– 2jΩ} (1 – e^{– 3jΩ})
  1 – e^{– jΩ}

Correct Option: B

so, u[n – 2] u[n – 6] u[n – 2] – u[n – 6] So, u[n – 2] – u[n – 6] = δ[n – 2] + δ[n – 3] + δ[n – 4] + δ[n – 6]

	_∞
X(e^jΩ) =		x[n].e^–jΩn
	^{n = – ∞}

= e^–2jΩ + e^–3jΩ + e^–4jΩ + e^–5jΩ