Question
Let $X$ be a discrete uniform random variable assuming only the value $c$ ( $X$ is thus a constant random variable). Show that for each positive integer $n$,$$E\left[X^n\right]=E[X]^n=c^n .$$
Step 1
For a discrete random variable $X$, the expectation $E[X]$ is defined as: $$ E[X] = \sum_x x \cdot P(X = x) $$ where the sum is taken over all possible values $x$ that $X$ can take, and $P(X = x)$ is the probability that $X$ equals $x$. Show more…
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