Let the moment generating function of a discrete random variable be Mx(t) = 3(1 + e^2t). Find the variance of X by using the MGF to find the first and second moments. Use the MGF of X to find the PMF of X. Find the variance of X by using the PMF of X as you would before we learned about MGFs. Check that it matches your answer from (a).
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(a) To find the variance of X using the moment generating function, we need to find the first and second moments. Show more…
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