Sign up ×
Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. It's 100% free, no registration required.

I am having trouble seeing the following consequence of the ultrametric inequality, which is supposed to be immediate.

If $|x+y|\leq \max{\{|x|,|y|\}}$, then, equality holds when $|x|\neq |y|$.

I looked up three books/notes and all of them just say that this is immediate.

share|cite|improve this question
The details are given in – lhf May 3 '11 at 15:02
@lhf: Thanks a lot. That was eating me up. – Milo Kunis May 3 '11 at 15:08

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.