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Ch. R - Algebra Review
Lial - Trigonometry 12th Edition
Lial12th EditionTrigonometryISBN: 9780136552161Not the one you use?Change textbook
Chapter 1, Problem 33

Let A = {-6, -12⁄4, -5⁄8, -√3, 0, ¼, 1, 2π, 3, √12}. List all the elements of A that belong to each set. Irrational numbers

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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 \(\frac{p}{q}\) where \(p\) and \(q\) are integers and \(q \neq 0\).
Go through each element of the set \(A = \{-6, -\frac{12}{4}, -\frac{5}{8}, -\sqrt{3}, 0, \frac{1}{4}, 1, 2\pi, 3, \sqrt{12}\}\) and determine if it can be expressed as a fraction of integers or not.
Identify \(-6\), \(-\frac{12}{4}\), \(-\frac{5}{8}\), \(0\), \(\frac{1}{4}\), \(1\), and \(3\) as rational numbers because they can be written as fractions of integers.
Recognize that \(-\sqrt{3}\) and \(2\pi\) are irrational because \(\sqrt{3}\) and \(\pi\) are well-known irrational numbers, and multiplying by \(-1\) or \(2\) does not change their irrationality.
Check \(\sqrt{12}\) by simplifying it: \(\sqrt{12} = \sqrt{4 \times 3} = 2\sqrt{3}\). Since \(\sqrt{3}\) is irrational, \(2\sqrt{3}\) is also irrational.

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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 simple fraction of two integers. Their decimal expansions are non-terminating and non-repeating. Examples include numbers like √3 and π, which cannot be precisely written as fractions.
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Set Membership and Classification

Understanding set membership involves determining whether an element belongs to a particular set based on its properties. Classifying numbers into sets like rational, irrational, integers, or real numbers helps organize and analyze them effectively.
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Simplification of Radicals and Fractions

Simplifying radicals and fractions helps identify the nature of numbers. For example, √12 can be simplified to 2√3, which is irrational. Simplifying fractions like -12/4 to -3 helps determine if the number is rational or integer.
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