(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

prove or disprove that E[X^2] = E(X)^2

2. Relevant equations

E[X] = [tex]\sum[/tex]x_{i}*pr(x_{i})

3. The attempt at a solution

I really don't know where to start, I believe that it is not true, so I should try to disprove it, and the easiest way to do that would be by counterexample... I don't understand expectation very well though, I could try to do a mathematical proof to show that they are not equal, but I don't know how to go about that either.

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# Homework Help: The Expectation of X and the Expectation of X squared (discrete math)

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