And this is how you retrieve the final answer for

the difference operative relation algebra.

So an example of that is that you want to list the students for

computer science majors who are not double-majoring in electrical engineering.

So in this case,

you will retrieve the table that has the computer science students.

And then you do a said difference between this table and

the table that represent the electrical engineering students.

So this way, you're going to remove from the computer science table

all the students that are also double-majoring in electrical engineering.

So this is basically a simple, so in this way, based on the schema we discussed

before, so we do a cse_majors from electrical engineering majors, that way.

And the output, again, as a rule, relational algebra,

the output of any relational algebra, the input is of relation, or

two relations, and the output is another relation.