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Ch. R - Algebra Review
Lial - Trigonometry 12th Edition
Lial12th EditionTrigonometryISBN: 9780136552161Not the one you use?Change textbook
Chapter 1, Problem 89

Factor each polynomial completely. See Example 6. 8t³ + 125

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1
Recognize that the polynomial \$8t^{3} + 125\( is a sum of cubes because \)8t^{3} = (2t)^{3}\( and \)125 = 5^{3}$.
Recall the sum of cubes factoring formula: \(a^{3} + b^{3} = (a + b)(a^{2} - ab + b^{2})\).
Identify \(a = 2t\) and \(b = 5\) in the expression \$8t^{3} + 125$.
Apply the formula: write the factorization as \((2t + 5)((2t)^{2} - (2t)(5) + 5^{2})\).
Simplify the terms inside the second parenthesis to get \((2t + 5)(4t^{2} - 10t + 25)\).

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Key Concepts

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

Sum of Cubes Formula

The sum of cubes formula states that a³ + b³ = (a + b)(a² - ab + b²). It is used to factor expressions where two terms are both perfect cubes added together. Recognizing 8t³ and 125 as cubes (2t)³ and 5³ allows applying this formula to factor the polynomial.
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Identifying Perfect Cubes

A perfect cube is a number or expression raised to the third power, such as 8 = 2³ or t³. Identifying each term as a perfect cube is essential before applying the sum or difference of cubes formulas. This step ensures the correct factorization method is used.
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Polynomial Factoring Techniques

Factoring polynomials involves rewriting them as products of simpler polynomials. Techniques include factoring out common factors, grouping, and special formulas like sum/difference of cubes. Understanding these methods helps break down complex expressions into factors.
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