Let X be a discrete random variable. Then the variance of X is: - Vidyadip

Question

Let $X$ be a discrete random variable. Then the variance of $X$ is$:$

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Answer

Since, the variance of a discrete random variable $X$ is given by$:$
Var$(X) = E(X^2) - (E(X))^2$
Hence, the correct alternative is option $(c).$

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