1. Which of the following is equal to Var(2X - 3Y), where X and Y are random variables on S? 4Var(X) + 12Cov(X, Y) + 9Var(Y) 4Var(X) - 12Cov(X, Y) + 9Var(Y) 2Var(X) + 6Cov(X, Y) + 3Var(Y) 2Var(X) - 6Cov(X, Y) + 3Var(Y)
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For random variables \(X\) and \(Y\), and constants \(a\) and \(b\), the variance is given by: \[ \text{Var}(aX + bY) = a^2 \text{Var}(X) + b^2 \text{Var}(Y) + 2ab \text{Cov}(X, Y) \] Show more…
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