Question

Arrange the given steps in the correct order to find a and b if a and b are two sets where a – b = {1, 5, 7, 8}, b – a = {2, 10} and a formula359.mml b = {3, 6, 9}.

Answer 1

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,
`a-b = \left \{ 1,5,7,8 \right \} \text{ and } b-a = \left \{ 2,10 \right \}\\`

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
`A\cap B= \left \{ 3,6,9 \right \}`.

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:

`a = \left \{ 1,3,5,6,7,8,9 \right \} \text{ and } b= \left \{ 2,3,6,9,10 \right \}\\`