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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

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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 \(\sqrt{12}\).

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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.
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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.
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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.
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