Skip to main content
Ch. R - Review of Basic Concepts
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063Not the one you use?Change textbook
Chapter 1, Problem 115

Let A = { -6, - 12/4 , - 5/8 , - √3, 0, 1/4 , 1, 2π, 3, √12}. List all the elements of A that belong to each set. Irrational numbers

Verified step by step guidance
1
Recall that irrational numbers are numbers that cannot be expressed as a ratio of two integers, meaning they cannot be written as a simple fraction and their decimal expansions are non-repeating and non-terminating.
Examine each element of the set \(A = \{ -6, - \frac{12}{4}, - \frac{5}{8}, - \sqrt{3}, 0, \frac{1}{4}, 1, 2\pi, 3, \sqrt{12} \}\) to determine if it is irrational.
Identify which elements are clearly rational: \(-6\) (an integer), \(- \frac{12}{4}\) (which simplifies to \(-3\), an integer), \(- \frac{5}{8}\) (a fraction), \(0\), \(\frac{1}{4}\) (a fraction), \(1\), and \(3\) are all rational numbers.
Focus on the elements involving square roots and \(\pi\): \(- \sqrt{3}\), \(2\pi\), and \(\sqrt{12}\). Recall that \(\sqrt{3}\) is irrational, \(\pi\) is irrational, and \(\sqrt{12}\) can be simplified to \(2\sqrt{3}\), which is also irrational.
Conclude that the irrational numbers in the set \(A\) are \(- \sqrt{3}\), \(2\pi\), and \(\sqrt{12}\).

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
3m
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Irrational Numbers

Irrational numbers are real numbers that cannot be expressed as a ratio of two integers. Their decimal expansions are non-terminating and non-repeating. Examples include numbers like √3 and π, which cannot be written as simple fractions.
Recommended video:
4:47
The Number e

Set Membership and Classification

Set membership involves determining whether an element belongs to a particular set based on defined properties. Classifying numbers into sets like rational or irrational requires understanding their characteristics and applying these definitions to each element.
Recommended video:
05:18
Interval Notation

Simplification of Expressions

Simplifying expressions, such as fractions or radicals, helps identify the nature of numbers. For example, simplifying -12/4 to -3 or √12 to 2√3 clarifies whether the number is rational or irrational, aiding in accurate classification.
Recommended video:
Guided course
05:09
Introduction to Algebraic Expressions