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Ch. R - Algebra Review
Lial - Trigonometry 12th Edition
Lial12th EditionTrigonometryISBN: 9780136552161Not the one you use?Change textbook
Chapter 1, Problem 113

Multiply. See Example 7. (√5 + 2)²

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Recognize that the expression \((\sqrt{5} + 2)^2\) is a binomial squared, which can be expanded using the formula \((a + b)^2 = a^2 + 2ab + b^2\).
Identify \(a = \sqrt{5}\) and \(b = 2\) in the expression.
Calculate each term separately: \(a^2 = (\sqrt{5})^2\), \(2ab = 2 \times \sqrt{5} \times 2\), and \(b^2 = 2^2\).
Write the expanded form by summing the three terms: \(a^2 + 2ab + b^2\).
Simplify each term where possible, such as \((\sqrt{5})^2 = 5\) and \(2^2 = 4\), then combine all terms to express the final expanded form.

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Key Concepts

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

Binomial Expansion

Binomial expansion is a method to expand expressions raised to a power, such as (a + b)². It follows the formula (a + b)² = a² + 2ab + b², allowing you to multiply and simplify the expression without direct multiplication.
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Square of a Sum

The square of a sum involves squaring a binomial by applying (a + b)² = a² + 2ab + b². This concept helps in breaking down complex expressions into simpler terms, making it easier to calculate or simplify.
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Simplifying Radicals

Simplifying radicals involves reducing square roots to their simplest form or combining like terms involving radicals. This is essential after expansion to write the final answer in a clear and simplified manner.
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