Fourier Series coefficient of time-domain signal is X[k]

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Fourier Series coefficient of time-domain signal is
X[k] = jδ[k – 1]– jδ[k + 1] + δ[k + 3] + δ[k – 3], ω_o = 2π
then corresponding time domain signal will be

1. 2(cos 3πt – sin πt)
2. – 2(cos 3πt – sinπt)
3. 2(cos 6πt – sin 2πt)
4. – 2(cos 6πt – sin 2πt)

Correct Option: C

= je^j2πt – je^{– j2πt} + e^j6πt + e^{– j6πt}
= – 2sin 2πt + 2cos 6πt