{
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  "body": "\n## Statement\n\nLet $X$ be a [[random variable|0DKRR22AEQ]] on a probability space $(S,P)$. Then the [[variance|007QED3E0Y]] of $X$ is the [[expected value|0DCT0QZVQ1]] of $X^2$ minus the square of the expected value of $X$:\n$$\\operatorname{Var}(X) = E(X^2) - E(X)^2.$$\n",
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  "msc": [
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  "name": "Alternative formula for the variance of a random variable",
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  "tag": "WTG11RMSK8",
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