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Let X, Y, Z be random variables with these properties: · E[X] = 3 and E[X²] = 10 Var(Y) = 5 E[Z] = 2 and E[Z2] = 7 • X and Y

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TOPIC:Covariance between random variables.

Given that, X, Y and Z are three nandom variables, having the properties as - E (x) = 3, E(x4) = 10. var(y) = 5 E(2) = 2 andNow, observe that, >) var(x) = E(x4-E(x) = 10 - 32 -1. = var (y) = 5 => var (2) = E(24) - 2) = 7-24 = 3. => Cov(x, ) = 0 As,

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