Let X1,X2,…,Xn be an independent trials process with density
f(x)=21e−∣x∣,−∞<x<+∞.
(a) Find the mean and variance of f(x).
(b) Find the moment generating function for X1, Sn, An, and Sn∗.
(c) What can you say about the moment generating function of Sn∗ as n→∞?
(d) What can you say about the moment generating function of An as n→∞?