Question

. Let ????1 be the function that assigns to each nonnegative integer its last digit. Note: The nonnegative integers is the set of positive integers along with zero, or all of the integers except for the negative integers. What is the domain of ????1?

Answer 1

The domain of a function is the complete set of possible values of the independent variable. In this case, the independent variable is any nonnegative integer. The nonnegative integers are the set of positive integers along with zero, then,

domain = {0, 1, 2, 3, ...} = natural numbers.