Question

find each union or intersection let A={1, 2, 3,} B={x|xis and even whole number less than 9} C={2, 5, 7, 10,} and D={x|xis an odd whole number less than 10}
I have to find A an upside down U C

Can someone help

Answer 1

A∩C is the intersection of A and C. That is, all the elements which appear in both A and C.

So, what do you think?

Answer 2

A={1, 2, 3, 5, 7, 10} C={2, 5, 7, 10} A U C={0, 2, 4, 5, 6, 7, 8, 10,}

Like this

Answer 3

Where did you get the 0? With the sets A and C you just gave,
AUC = {1,2,3,5,7,10}
A∩C = {2,5,7,10}

Note that AUC = A and A∩C = C
because C is a subset of A

You won't get any 0 elements unless you start working with B.