Question

Please help :)

U={3,5,7,9,11,13,15}
A={3,5,7,9}
B={7,9,11,13}
C={3,11,15}

a U c' ??

Answer 1

first you need to find C'

how do we do this?

Answer 2

That seems to be where I am stuck, I know that I am looking for the compliment of C... correct?

Answer 3

exactly, basically the set of things that are in U, but NOT in C

Answer 4

Right, Ok so I have done that so far and I came up with {5,7,9,15} But I dont think that that is the completed answer....

Answer 5

15 is in C, so how can it be in C' ?

Answer 6

Oh I am sorry I ment to type 13

Answer 7

good, C ' = {5,7,9,13}

Answer 8

Now simply combine these numbers in C ' with the numbers in A

A U C ' = {3,5,7,9} U {5,7,9,13}

A U C ' = {3,5,7,9, 5,7,9,13}

A U C ' = {3,5,7,9,13} .. remember to toss out duplicates and sort

Answer 9

Ok but there is still another step correct?

Answer 10

no that's the last step

you basically "glue" the two sets A and C' together, sort and toss out duplicates

Answer 11

I see!! Thanks so very much! You were so clear in explaining!!

Answer 12

you're welcome