Binary Relations: A={1,2,3} B={a,b} When AxB={(1,a),(2,a),(3,a),(1,b),(2,b),(3,b)}

[Eydiaz]

I need help in finding R.
I would appreciate a step by step explanation, as I really want to understand how to find the relation.
Example:
A={1,2,3} B={a,b}
When
AxB={(1,a),(2,a),(3,a),(1,b),(2,b),(3,b)}
How did my professor get this answer?

R={(2,a),(1,b),(2,b),(3,b)}

Thank you.

 

[Dr.Peterson]

What is the question? Please quote the entire problem as given to you.

Any subset of AxB is a relation from A to B; R as shown is just one of many. Did you omit some specific description of what R is to be, or was it just given as an example?

 

[pka]

I need help in finding R.
I would appreciate a step by step explanation, as I really want to understand how to find the relation.
Example: A={1,2,3} B={a,b}
When AxB={(1,a),(2,a),(3,a),(1,b),(2,b),(3,b)}

How did my professor get this answer?
R={(2,a),(1,b),(2,b),(3,b)}

Unless you can tell us the exact wording of the question there is no way to say why that is the answer.
\(\displaystyle \mathcal{R}=\{(2,a),(1,b),(2,b),(3,b)\}\) This could have many definitions.
Please look at your class notes to see if that is preceded by some definition.