Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have this venn diagram enter image description here

For which i have shade (A ∩ B ) ∪ C. I see where A and B intersect, but i don't how a union should appear between the intersection and C. Could someone clarify where i am going wrong?

share|cite|improve this question
up vote 2 down vote accepted

The red area is $(A\cap B)\cup C$

AB + C

The red points are the ones that are either in the intersection $A\cap B$, or in $C$ (or in both, but there are no such points in this case). That's what union means, after all.

share|cite|improve this answer
So something like A ∩ ( B ∪ C)’ would look like this – stats Sep 1 '14 at 21:13
@stats Yes, that's right. – Arthur Sep 1 '14 at 21:54

You simply shade $A \cap B$ which is the common area for $A$ and $B$, then you shade $C$ too because in a way you're "combining the two sets". All of what's in $A \cap B$ AND in $C$ is in the union.

share|cite|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.