Question

The  z-transform of δ[n+k]>0 is __________

(a) Z^-k, Z≠0

(b) Z^k, Z≠0

(c) Z^-k, all Z

(d) Z^k, all Z

The question was asked in a job interview.

Question is from Properties of Z-Transforms topic in section Z-Transform and Digital Filtering of Signals and Systems

Answer 1

The correct option is (d) Z^k, all Z

Best explanation: Performing z-transform on δ[n+k], we get,

X (z) = \(∑_{n=0}^∞ x[n]z^{-n}\)

= Z^k, all Z