Assume I have 4 sets: $A$, $B$, $C$, and $D$.
What is the mathematical notation to indicate that all of these sets are pairwise disjoint?
I can obviously type:
$$A \cap B = \emptyset$$ $$A \cap C = \emptyset$$
etc.
But I am looking for a more succinct and mathematically correct way of expressing this.
$\endgroup$ 41 Answer
$\begingroup$If you have indexed family $\{A_i\}_{i\in I}$, then you can write $A_i\cap A_j=\emptyset$, $i\neq j$. If not, I don't see any problem in just stating: "Let $A,B,C,D$ be pairwise disjoint." This will probably be more clear than any notation you could come up with, including my own suggestion.
$\endgroup$
