Suppose that a filter transfer function HS 1s a is discret

Suppose that a filter transfer function H(S) = 1/s + a is discretized for T = 1. Estimate the upper bound of \"a > 0\" for stability when the ZOH equivalence is used:

Solution

Ans: Suppose the filter transfer function a=0,

then the output of the transfer function is Infinity.

So the ans is Infinity. Option:(b)