(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Let U= all real numbers, A=[2,9), B=(0,1], C=[-1,4]. Express in interval notation: (A union B) - C

2. Relevant equations

A union B includes all elements that are in either A or B, including any objects that happen to lie in both A and B.

The difference A - B consists of all objects that are elements of A and are not elemnts of B

3. The attempt at a solution

I think the interval is from (4,9). A union B would be (0,1]union[2,9], then you remove from [-1, 4]. The only reason why I don't know if I'm right is because of the gap in the union of A and B. I don't know if that has any effect on the answer.

If (4,9) is correct then would it be safe to assume that (A union B) - C = A-C ?

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Simple Set Operation

**Physics Forums | Science Articles, Homework Help, Discussion**