what is set - builder form and roster form

Hi!

Here is the answer to your query.

 

In set builder form, the set is described by a characterizing property of its elements. In order to describe a set, a variable, say x is written inside the braces and then after putting a colon the common property P (x) possessed by each element of the set is written within the braces.

 Example:

The set P = {1, 2, 3, 4, 5, 6, 7, 8} can be written in set builder form as P = {x: x ε N, x ≤ 8}

The set Q = {1, 4, 9, 16... 100} can be written in set builder form as Q = {x ²: x ε N, 1 ≤ x ≤ 10}

 

In roster form, the set is described by listing elements, separated by commas, within the braces { }.

Let A = {x: x is a set of even natural numbers between 15 and 45} .Write this set in roster forms. 

A = {x: x is a set of even natural numbers between 15 and 45}.

The roster form of this set can be written as:

A = {16, 18 20 22, 24 26, 28, 30, 32, 34, 36, 38, 40, 42, 44}

 

Cheers!