# Thread: End points and brackets

1. ## End points and brackets

Often we'll receive questions that have a graph looking like the first picture I posted, with either circle or dot end points.
Also, sometimes we'll get a domain given as [-2,7).

I don't understand what these different brackets and end points mean. Please explain! Thanks

2. Square brakets mean a closed interval (dot), and round brackets mean an open interval (circle). so [-2,7) means $-2 \le x <7$ so the closed endpoint includes the bound, but the open endpoint doesn't.

3. Ah...that's what I assumed. That it was relatively simple, but I just didn't get it.
Thanks. That little tidbit is sure to come in handy.