grandes-ecoles 2021 Q36

grandes-ecoles · France · centrale-maths1__mp Not Maths Dominated Convergence and Truncation Arguments for Discrete Variables
Let $X$ be a discrete random variable with finite expectation. Show that $$\mathbb{E}\left(X \mathbb{1}_{|X| \leqslant C}\right) \xrightarrow{C \rightarrow +\infty} \mathbb{E}(X).$$
Let $X$ be a discrete random variable with finite expectation. Show that
$$\mathbb{E}\left(X \mathbb{1}_{|X| \leqslant C}\right) \xrightarrow{C \rightarrow +\infty} \mathbb{E}(X).$$