We have been given the difference of two sets in two different orders and we are supposed to write the sets a and b.
We are given, [tex]a-b = \left \{ 1,5,7,8 \right \} \text{ and } b-a = \left \{ 2,10 \right \}\\[/tex]
We know that the difference a-b represents the elements which are present in a but they are not present in b.
Similarly, b-a represents the elements which are present in b but not present in a.
Since we have been given that [tex]A\cap B= \left \{ 3,6,9 \right \}[/tex].
Therefore, we can include these elements to a-b and b-a in order to get the sets for a and b, as shown below:
[tex]a = \left \{ 1,3,5,6,7,8,9 \right \} \text{ and } b= \left \{ 2,3,6,9,10 \right \}\\[/tex]
