Let $P = (\Omega, \mathcal{F}, \mathbb{P})$ be a D1159: Probability space such that
(i) | $X, Y : \Omega \to \mathbb{R}$ are each a D3161: Random real number on $P$ |
(ii) | \begin{equation} \mathbb{E} |X|, \mathbb{E} |Y| < \infty \end{equation} |
(iii) | $\alpha, \beta \in \mathbb{C}$ are each a D1207: Complex number |
Then
\begin{equation}
\mathbb{E}(\alpha X + \beta Y)
= \alpha \mathbb{E} X + \beta \mathbb{E} Y
\end{equation}