Assignment:
For a generic function g(n) defined for n ≥ 0, we define its z-transform as
Z(g)(z)= ∞Σn=0 g(n)zn
where z is a complex variable. With reference to the bidirectional random walk of Example 7.2 M develop the following points.
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a) Prove that
b) Using the result of the previous point, derive the exact expression of
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c) Prove that Z{ƒ0,0}= 1 - √1-4pqz2.
d) Using the result of the previous point, derive the exact expression of f0,0 and of f0,0(n) for any positive integer n.