Let Z be a random vector with 4 components and covariance
Chapter , Problem 31(choose chapter or problem)
Let Z be a random vector with 4 components and covariance matrix \(\sigma^2 I\). Let \(U=Z_1+Z_2+Z_3+Z_4\) and \(V=\left(Z_1+Z_2\right)-\left(Z_3+Z_4\right)\). Use matrix methods to find \(\operatorname{Cov}(U, V)\).
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