In 1930, Tarski observed that align* ||r|-|s||=|r-s|+ |r+s|- (|r|+|s|), r, s R. align* In 2008, Maligranda converted the previous equality into inequalities that are valid in every normed linear space. We derive non-Archimedean versions of Tarski-Maligranda inequalities. Difference between Archimedean and non-Archimedean inequalities is surprising.
MAHESH KRISHNA K (Wed,) studied this question.