Suppose that $f : \Bbb R \to \Bbb R$ is an integrable function. Show that the map $h(x)= \int_{- \infty}^x f(t) \ dt$ is continuous.
What I’ve tried to do is show that $h$ is continuous with preimages, but that doesn’t seem like it’s going to work. For some $O$ open in $\Bbb R$ the preimage of $O$ under $h$ isn’t something that’s easy to work with. Is there some ”trick” that I’m not familiar with to prove continuity of this kind of map?
lebesgue-integral
tag. – WhatsUp Oct 20 '21 at 18:47