# Unfamiliar Notation

1. Jan 26, 2010

### Lank

1. The problem statement, all variables and given/known data

Having trouble recognizing this notation.
Let Ai = {i, i + 1, i + 2, . . . } for i = 1, 2, . . . . What
are:

$$\bigcup$$ A (subscript i)
i=1

and

$$\bigcap$$ A (subscript i)
i=1

2. Relevant equations
I know what the $$\bigcup$$ or $$\bigcap$$ notation means in sets and subsets, but not in sequences and summations.

3. The attempt at a solution

I don't need it explained, I simply need to know what the $$\bigcup$$ and $$\bigcap$$ stands for so I can read up on them. Thanks guys. I can also upload the pdf attachment if needed.

Last edited: Jan 26, 2010
2. Jan 26, 2010

### Staff: Mentor

$$\bigcup$$ - union - A1 U A2 U ... U An
$$\bigcap$$ - intersection - same as above but with the intersection symbol

3. Jan 26, 2010

Thanks.