Union
$$A \cup B =$$
{ astronomy, biology, chemistry, equality, fraternity, liberty, mathematics, physics, sociology }
Symmetric Difference
$$A \ominus B =$$
{ astronomy, biology, chemistry, equality, fraternity, liberty, mathematics, physics, sociology }
Difference
$$A - B =$$
{ astronomy, biology, chemistry, mathematics, physics, sociology }
Cartesian Product
$$A \times B =$$
{ (astronomy, equality),
(astronomy, fraternity),
(astronomy, liberty),
(biology, equality),
(biology, fraternity),
(biology, liberty),
(chemistry, equality),
(chemistry, fraternity),
(chemistry, liberty),
(mathematics, equality),
(mathematics, fraternity),
(mathematics, liberty),
(physics, equality),
(physics, fraternity),
(physics, liberty),
(sociology, equality),
(sociology, fraternity),
(sociology, liberty) }