Let $M = (X, \mathcal{F}, \mu)$ be a D1158: Measure space.
Let $f : X \to [- \infty, \infty]$ be an D1921: Absolutely integrable function on $M$ such that

(i)	$f =_{a.e.} 0$

Then \begin{equation} \int_X f \, d \mu = 0 \end{equation}