Expectation

Sums of random variables (from M343)

$$ E(X1+X2) = $$

Expectation of a function of a random variable
$$E[g(X)] = \sum_{x \in \Omega_X} g(x) p_X  (x) $$ if X is discrete

$$E[g(X)] = \int_{-\infty}^\infty g(x) f(x) dx $$ if X is continuous

@todo