1. I know var(x)=E(x^2)-E(x)^2; is there a repeated way to use this to attain var(x^2)? Or how in general, without resorting to integration, can I calculate it?(adsbygoogle = window.adsbygoogle || []).push({});

2. We typically deal with "i.i.d random variables X_i" and do things like find var(X) given E(X^2) etc..it never occurred to me until now, but if the X's are "independent" then why is E(x^2) not equal to E(x)*E(X)?? (the answer I'm awaiting will probably be obvious, though I can't figure this out right now)

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# 2 simple stats questions

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