- #1
Yegor
- 147
- 1
T is an index set. And for each [tex]t \in T[/tex] [tex] A_t [/tex] is a set
[tex]\bigcup_{t \in T} A_t = \{x : \exists t \in T with x \in A_t \}[/tex]
What means this [tex]\bigcup[/tex] symbol and entire expression?
And question on index set: is it used just for orderring any other set?
[tex]\bigcup_{t \in T} A_t = \{x : \exists t \in T with x \in A_t \}[/tex]
What means this [tex]\bigcup[/tex] symbol and entire expression?
And question on index set: is it used just for orderring any other set?