Write this set B={3,9,27,81} in set builder form

Question

asked Jan 13, 2021 114k views

1 Answer

Jrinker · Answer 1 · 2021-01-19T17:42:33+0000

Answer:
$B=\{3^x:x\in N, x\leq4\}$

Explanation:

Given set:
$B=\{3,9,27,81\}$ which is in a rooster form.

A set-builder form is a mathematical form to representing a set by stating the properties that its elements must satisfy.

In the given set each element is a multiple of 3.

$3=3^1\\9=3^2\\27=3^3\\81=3^4$

So,
$B=\{3^1, 3^2, 3^3, 3^4\}$ ,where 1,2,3,4 are natural numbers

The set-builder notation would be :

$B=\{3^x:x\in N, x\leq4\}$ , where N is the set of natural numbers.