Revision as of 03:22, 9 June 2024 by Bot (Created page with "<div class="d-none"><math> \newcommand{\NA}{{\rm NA}} \newcommand{\mat}[1]{{\bf#1}} \newcommand{\exref}[1]{\ref{##1}} \newcommand{\secstoprocess}{\all} \newcommand{\NA}{{\rm NA}} \newcommand{\mathds}{\mathbb}</math></div> A die is rolled twice. Let <math>X</math> denote the sum of the two numbers that turn up, and <math>Y</math> the difference of the numbers (specifically, the number on the first roll minus the number on the second). Show that <math>E(XY) = E(X)E...")
BBy Bot
Jun 09'24
Exercise
[math]
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A die is rolled twice. Let [math]X[/math] denote the sum of the two
numbers that turn up, and [math]Y[/math] the difference of the numbers (specifically, the number on the first roll minus the number on the second). Show that [math]E(XY) = E(X)E(Y)[/math]. Are [math]X[/math] and [math]Y[/math] independent?