2. Suppose the mgf of a discrete random variable X is $M_X(t) = \frac{1}{4}e^{-2t} + \frac{1}{4}e^{-t} + \frac{1}{8}e^{2t} + \frac{3}{8}e^{5t}$ (a) Find the expectation E(X) (b) Find the expectation E(X$^2$) (c) Find the expectation E(X$^2$ - 3X + 4) (d) Write down the pmf of X
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Step 1: The mgf of a discrete random variable X is given by: $M_X(t) = E(e^{tX})$ Show more…
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