I have been doing a unit in my probability theory and statistics course on Markov's inequality and Chebyshev's theorem. This below question is stumping me, I'm not quite sure where to start. The only hint I have gotten is this: The key to explaining this is using Markov's inequality. Markov's inequality tells usk * Prob[Y > k]

If we carefully choose our k and Y we can solve the above problem. You setY =(X - Expect[X])^2 , but it may be easier to choose a Y such that Expect[Y] = Far[X].

Could I have some advice on how to tackle this problem? Thank you!

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