Question

write each set in the indicated form.
if you need to use \...\ to indicate a pattern, make sure to list at least four elements of the set.

as you answer below, remember that the natural numbers are just the counting numbers. this means that 0 is not a natural number, and negative numbers are not natural numbers either.

(a) roster form: {6, 9, 12}
descriptive form: select
(b) descriptive form: the set of even natural numbers.
roster form:

Explanation:

(a) Step1: Identify set pattern

Elements 6,9,12 are multiples of 3, natural numbers from 6 to 12.

(b) Step1: Define even natural numbers

Even natural numbers are positive counting numbers divisible by 2, starting at 2.

(b) Step2: List elements with pattern

List first 4 elements, add ... for continuation: $\{2, 4, 6, 8, ...\}$

Answer:

(a) Descriptive form: The set of natural numbers that are multiples of 3 starting from 6 up to 12
(b) Roster form: $\{2, 4, 6, 8, ...\}$