what does the inverse membership symbol means?

Question

I know that the symbol $$ \in $$ stands for membership, but what does the symbol $$ \ni $$ stand for?

Because I know that in the set membership, one symbol stands for subset and the other ones for superset, but I cannot find the meaning of the other symbol

Thanks

It's just set membership written the other way round: $x \in X$ and $X \ni x$ mean the same thing. — Johannes Kloos, Jan 29 '13 at 14:00
Similar looking symbols are also used by some authors for "such that" - see this question. — Math Gems, Jan 29 '13 at 14:36

score 2 · Answer 1 · edited Sep 29 '15 at 19:28

2

Because $a < b$ means the same thing as $b > a$ and $A \subset B$ means the same thing as $B \supset A$, one should not use the mirror image of $\in$ to mean "such that". It is a bad, confusing notation.

edited Sep 29 '15 at 19:28

user 1

7,447

answered May 22 '13 at 20:40

Jean -Claude Falmagne

21

score 1 · Accepted Answer · answered Jan 29 '13 at 13:59

1

Sometimes you want to write the set before the element. $A \ni x$ means exactly the same as $x \in A$.

answered Jan 29 '13 at 13:59

mrf

43,639

what does the inverse membership symbol means?

2 Answers2