Union
$$A \cup B =$$
{ argumentative, descriptive, earth, expository, fire, metal, narrative, water, wood }
Symmetric Difference
$$A \ominus B =$$
{ argumentative, descriptive, earth, expository, fire, metal, narrative, water, wood }
Difference
$$A - B =$$
{ argumentative, descriptive, expository, narrative }
Difference
$$B - A =$$
{ earth, fire, metal, water, wood }
Cartesian Product
$$A \times B =$$
{ (argumentative, earth),
(argumentative, fire),
(argumentative, metal),
(argumentative, water),
(argumentative, wood),
(descriptive, earth),
(descriptive, fire),
(descriptive, metal),
(descriptive, water),
(descriptive, wood),
(expository, earth),
(expository, fire),
(expository, metal),
(expository, water),
(expository, wood),
(narrative, earth),
(narrative, fire),
(narrative, metal),
(narrative, water),
(narrative, wood) }
Text types