Z Transform: Example Important Solved Problems with formula, steps, derivation and answer based on Inverse Z Transform - Inverse integral method (Cauchy's residue theorem).
INVERSE Z-TRANSFORM
If
Z[x(n)] = X(z) then Z‒1[X (z)] = [x(n)]
Z‒1[X(z)]
can be found out by any one of the following methods.
INVERSE
Z-TRANSFORM: CAUCHY'S RESIDUE THEOREM
From
the relation between the Z‒transform and Fourier transform of a sequence we get

By
Cauchy's residue theorem
ʃC
X(z) zn-1 = 2πi [sum of the residues of X(z) zn-1 at the isolated
singularities]
i.e.,
x(n) = sum of the residues of X(z) zn-1 at the isolated
singularities
Note:
Take the contour C such that all the poles of the function X(z)zn-1
lie within the contour.








Transforms and its Applications: UNIT 2: Z Transform : Tag: Engineering mathematics, Maths : - Inverse Z Transform: Inverse integral method (Cauchy's residue theorem)
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