Domain & Range Homework: Difference Explained

[dranseth]

Homework Statement

I don't really know how to ask this, so I'll get straight into an example.

x:x\in(-\infty,\infty) but x\neq1
x:x\in(-\infty,1)\cup(1,\infty)

what is the difference between these two intervals?

Homework Equations

The Attempt at a Solution

 

[Dick]

There is no difference. They are both the whole real line except for x=1. Why do you ask?

 

[dranseth]

At times when I look at answers in the back of the book, it is one or the other. There didn't appear to be any consistency, so I was wondering if I was possibly missing something..

 

[HallsofIvy]

Yes, you are missing seeing that they are the same thing!