Question
Prove that $\operatorname{cov}(X, Y)=\operatorname{cov}(Y, X)$ for both discrete and continuous random variables $X$ and $Y$.
Step 1
The covariance is defined as: \[ \operatorname{cov}(X, Y) = \mathbb{E}[(X - \mathbb{E}[X])(Y - \mathbb{E}[Y])] \] where \(\mathbb{E}[X]\) and \(\mathbb{E}[Y]\) are the expected values of \(X\) and \(Y\), respectively. Show more…
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Key Concepts
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