1. ## complement of sets

U= {a, b, c, d, e, f, g, h}
A= {a, c, f, g}
B= {a, e}
C= {b, h}

compute: $\displaystyle \overline{C}\cap\overline{C}$
(the complement line is supposed to go over the whole thing but i didn't know how to do that, oops ^^)
i just started discrete math so the answer might be easy, but how is it not just the empty set? how can you intersect the complement of something with itself? any help would be appreciated, thanks =)

2. Originally Posted by e____o
U= {a, b, c, d, e, f, g, h}
A= {a, c, f, g}
B= {a, e}
C= {b, h}

compute: $\displaystyle \overline{C}\cap\overline{C}$
(the complement line is supposed to go over the whole thing but i didn't know how to do that, oops ^^)
i just started discrete math so the answer might be easy, but how is it not just the empty set? how can you intersect the complement of something with itself? any help would be appreciated, thanks =)
You need to know that $\displaystyle A \cap A = A$. The complement of $\displaystyle A$ is the set with elements of universal set $\displaystyle U$ that don't belong in $\displaystyle A$. I think this might help.

3. Originally Posted by javax
You need to know that $\displaystyle A \cap A = A$. The complement of $\displaystyle A$ is the set with elements of universal set $\displaystyle U$ that don't belong in $\displaystyle A$. I think this might help.
thanks, that helps =) so the problem is basically asking for the complement of C?

4. Originally Posted by e____o
thanks, that helps =) so the problem is basically asking for the complement of C?
Yes I think so.