Question

Given the z-transform pair 3^nn^2 u[n] ↔ X (z). The time signal corresponding to X(z^-1) is ___________

(a) n^23^-nu[n]

(b) n^23^-nu[-n]

(c) \(\frac{1}{n^2}  3^{\frac{1}{n}} u[n]\)

(d) \(\frac{1}{n^2}  3^{\frac{1}{n}} u[-n]\)

I got this question by my school teacher while I was bunking the class.

Asked question is from Inverse Z-Transform in chapter Z-Transform and Digital Filtering of Signals and Systems

Answer 1

Right choice is (b) n^23^-nu[-n]

To elaborate: Y (z) = X (\(\frac{1}{z}\)) ↔ y[n] = X [-n]

Or, y[n] = n^23^-nu[-n].