Let $X_1$, $X_2$ and $X_3$ be random sample from $N(1, 1)$.\n a) Find the mean and variance of $Y = X_1 + 3X_2 - X_3$ using \n i) The direct method that applies definition of expectations and its property.\n ii) The moment generating function (MGF) method.
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Step 1: We know that E(X1) = E(X2) = E(X3) = 1 and Var(X1) = Var(X2) = Var(X3) = 1. Show more…
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