Изменения
Нет описания правки
<tex>E_\xi = \sum \xi(\omega)*p(\omega)</tex>
Теорема
<tex>\sum_{\omega\epsilon\Omega} \xi(\omega)*p(\omega) = </tex>
<tex>\sum_a \sum_{\omega|p(\omega) = a} \xi(\omega)*p(\omega) = \sum_a \sum_{\omega|\xi(\omega)=a}p(\omega) = \sum_a p(\xi = a)</tex>
==Пример==
<tex> \xi(i) = i </tex>
<tex>\sum E_\xi(\omega)= 1*1/6+2*p(\omega) = \sum_a \sum_(\omega|p(\omega)=a) \xi(\omega)1/6 ... +6*p(\omega) = \sum_a p(\xi 1/6 = a)3.5</tex>
