Union
$$A \cup B =$$
{ agent, define, deliver, develop, discover, other, product, truth }
Symmetric Difference
$$A \ominus B =$$
{ agent, define, deliver, develop, discover, other, product, truth }
Difference
$$A - B =$$
{ define, deliver, develop, discover }
Difference
$$B - A =$$
{ agent, other, product, truth }
Cartesian Product
$$A \times B =$$
{ (define, agent),
(define, other),
(define, product),
(define, truth),
(deliver, agent),
(deliver, other),
(deliver, product),
(deliver, truth),
(develop, agent),
(develop, other),
(develop, product),
(develop, truth),
(discover, agent),
(discover, other),
(discover, product),
(discover, truth) }