Problem :
Let set A = {1, 2, 3} and set B = {4, 5}. What is their Cartesian
product A×B?
A×B = {(1, 4),(1, 5),(2, 4),(2, 5),(3, 4),(3, 5)}. This is every
possible ordered pair from which the first element is taken from
A and the
second element taken from
B.
Problem :
What is the Cartesian product of the set of real numbers and itself?
The Cartesian product is every ordered pair in the coordinate plane.
Problem :
What is the Cartesian product of the set of positive real numbers with itself?
The Cartesian product is every ordered pair in the first
quadrant of the coordinate plane.
Problem :
What is the domain and range of the relation {(2, 4),(4, 8),(8, 16)}?
Domain
D = {2, 4, 8}. Range
R = {4, 8, 16}.
Problem :
What is the domain and range of the relation y = ±?
Domain
D is real numbers
> 0. Range
R is all real numbers.