0
$\begingroup$

I have a question on the following definition

enter image description here

I don't quite get why the definition says " if f is identically zero in a neighborhood of a", I mean there's nothing wrong with that I just don't get why it's not saying " if f vanishes everywhere" since $f$ would be constant zero if it would vanish on an open set due to the identity theorem, right?

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.