Question

Let A = {red, yellow} and let B = {1, 2, 3}. Find A X B.

{(red, 1), (red, 2), (red, 3), (yellow, 1), (yellow, 2), (yellow, 3)}

{red, yellow, 1, 2, 3}

{ }

{1, 2, 3}

Answer 1

The first option is correct....
In cartesian product...
You group together all possibilities... from A and from B
So you get
if A ={1,2} and B={1,2}
Then AXB = {(1,1),(1,2),(2,1),(2,2)}

Also if A = R(set of real no.s) and B = R(set of real no.s)
then AXB = RXR = set of all points in the cartesian or x-y plane

Think of other such examples....
Say A = R, B= R, and C=R
Wht is AXBXC?
Similarly if A = R and B =set of purely imaginary no.s,
wht is AXB?

Answer 2

A X B. is a set of all ordered pairs (a,b) such that a is an element of A and b is an element of B.
That is,
Let A={1,2} and B={3,4}
then AxB={(1,3),(1,4),(2,3),(2,4)}
Nw can u find?