Cartesian Products: Set of Ordered Pairs?

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The Cartesian product A × B is defined as the set of all possible ordered pairs (a, b) where a is an element of set A and b is an element of set B. For example, with A = {1, 2, 3} and B = {cow, sheep}, the correct representation of A × B is {(1, cow), (1, sheep), (2, cow), (2, sheep), (3, cow), (3, sheep)}. It is important to note that the order of elements in the pairs matters, making Cartesian products non-commutative; (1, cow) is not the same as (cow, 1). The discussion clarified the distinction between "all possible ordered pairs" and "all ordered pairs," emphasizing that the Cartesian product includes distinct pairs based on the order of elements. Understanding these concepts helps in grasping the fundamentals of set theory and Cartesian products.
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Is the cartesian product (A \times B) the set of ALL POSSIBLE ordered pairs (a, b) such that a is an element of A and b is an element of b, or is it simply the set of "all ordered pairs?"
 
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Question for you: A = {1, 2, 3} and B = {cow, sheep}.Write down A x B.
 
{1 cow, 2 cow, 3 cow; 1 sheep 2 sheep 3 sheep}?

So it's all possible ordered pairs?
 
QuantumP7 said:
{1 cow, 2 cow, 3 cow; 1 sheep 2 sheep 3 sheep}?

correct

So it's all possible ordered pairs?

Your question is more a language thing about the word "possible".
 
Yeah, I've gotten hung up on the semantics of all possible vs. all. But I think that I understand what's going on.

But does anyone know what the Venn diagram of a cartesian product set looks like?
 
Outlined said:
correct
Not correct; AxB should consists of ordered pairs.
"1 cow" is not an ordered pair, "(1,cow)" is.
QuantumP7 said:
all possible vs. all.
What is or could be the difference?
 
QuantumP7 said:
Is the cartesian product (A \times B) the set of ALL POSSIBLE ordered pairs (a, b) such that a is an element of A and b is an element of b, or is it simply the set of "all ordered pairs?"

If I understand you about trying to say that for example (1,cow) and (cow,1) are the same, then that is false. Cartesian products are not in general commutative since A x B takes the element of A and then B in the ordered pair. if A and B are the same set then you will have this property ( (a,b) and (b,a) are part of A x B) but generally this is not the case.
 
Landau said:
Not correct; AxB should consists of ordered pairs.
"1 cow" is not an ordered pair, "(1,cow)" is.

You're right. My fault.

What is or could be the difference?

I get it now. All Cartesian products = all products. I think that I was just over-thinking the whole thing. Thanks so much!

chiro said:
If I understand you about trying to say that for example (1,cow) and (cow,1) are the same, then that is false. Cartesian products are not in general commutative since A x B takes the element of A and then B in the ordered pair. if A and B are the same set then you will have this property ( (a,b) and (b,a) are part of A x B) but generally this is not the case.

I see now. Thank you so much.
 

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