Originally Posted by

**yoonsi** Hey everyone,

Thanks for taking the time to look at my thread.

I have this question, and a particular part of it is confusing me, I was hoping someone could help me reach the right place.

The question is:

Let A = {(x,y) is element of ZxZ : | x-y | <= 1},

B = {0,1,2,3,4,5}

C = {3,4,5}

Determine |A Intersection (B x C) |

Now I know what im supposed to do. Determine the cardinality of the resultant set of A Intersection (B x C). B and C are right there, however

acquiring the members of A is confusing me. It appears to me that the set in A would have elements consisting of ordered pairs, because of (x,y), but this doesn't seem right to me. Z x Z means the domain of Integers by cartesian product right? so like... (0,0), (0,1), (0,2)... then (1,0), (1,1)...

and so on? I believe the set A is supposed to have singular elements in it, as opposed to pairs, but how do I get this set. I would appreciate any help =] and I apologise for the vagueness of the question. I haven't done maths for a few years and this is my first experience with this branch.

Cheers =]