Question

Find A ∩ (B C).

A = {2, 3, 5, 8}
B = {3, 5, 7}
C = {2, 4, 8}


A.{ }
B.{2, 8}
C.{2, 3, 4, 5, 7, 8}
D.{2, 3, 5, 8}

Answer 1

There's a missing symbol between B and C. \(\large\cup\) ?

Answer 2

yes it a U

Answer 3

*its*

Answer 4

That U there means union... can you find B U C?

(HINT: It's the set of all elements of B and C, together, but don't repeat any)

Answer 5

sorry i don't understand what you mean.

Answer 6

Example:
P = {1,2,3,4}
Q = {2,4,6,8}

P U Q = {1,2,3,4,6,8}
or in other words, the elements of P and Q put together.

Answer 7

so it would be 2,3,4,5,7,8?

Answer 8

That is correct ^_^
Now the intersection sign \(\large \cap\)
A \(\cap\) {2,3,4,5,7,8}
Unlike the union, the intersection is simply all the elements A and that set HAVE IN COMMON

Looking at the P and Q examples I gave earlier,
P \(\large \cap\) Q = {2,4}
(the only elements P and Q have in common)

Answer 9

Alright Thanks.

Answer 10

oh, post your answer, if you're willing :)

Answer 11

C.{2, 3, 4, 5, 7, 8}

Answer 12

No. That's just B U C

Answer 13

You're asked for A \(\cap\) (B U C)
I told you, it's the set of elements A has in common with (B U C)

Answer 14

You don't see the element '4' in set A, do you?

Answer 15

so is it D.{2, 3, 5, 8}?

Answer 16

Yes.
Because those are precisely the elements which are both in A and in B U C

Answer 17

Thanks again i really appreciate your help.

Answer 18

A ∩ (B ∪ C)