Chapter 0: Problem 52
In Exercises \(49-56,\) factor using the formula for the sum or difference of two cubes. $$x^{3}-27$$
Short Answer
Expert verified
The factored form of \(x^{3}-27\) is \((x-3)(x^{2}+3x+9)\).
Step by step solution
01
Identify the Cubes
In the expression \(x^{3}-27\), \(x^{3}\) is the first cube and \(27\) is the second cube. So, \(a^{3}=x^{3}\) which means \(a=x\), and \(b^{3}=27\) which means \(b=3\) as \(3^{3}\) equals to \(27\).
02
Substitute \(a\) and \(b\) into the Formula
Substitute \(a=x\) and \(b=3\) into the formula for the difference of two cubes: \((a-b)(a^{2}+ab+b^{2})\). So, the factored form is \((x-3)(x^{2}+3x+9)\).
03
Check the Factored Expression
One can check the factored expression by expanding \((x-3)(x^{2}+3x+9)\) and verifying that it equals to the original expression \(x^{3}-27\). Expanding \((x-3)(x^{2}+3x+9)\) yields \(x^{3}-27\), which confirms that the factored form is correct.
Unlock Step-by-Step Solutions & Ace Your Exams!
-
Full Textbook Solutions
Get detailed explanations and key concepts
-
Unlimited Al creation
Al flashcards, explanations, exams and more...
-
Ads-free access
To over 500 millions flashcards
-
Money-back guarantee
We refund you if you fail your exam.
Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Understanding Cubes
Cubes are a fascinating concept in mathematics, representing the multiplication of a number by itself twice. In simple terms, when we say a number is cubed, it means it is raised to the power of three.
- For example, when we say \( x^3 \), it implies \( x \times x \times x \).
- Similarly, \( 3^3 \) means \( 3 \times 3 \times 3 \), which equals \( 27 \).
Difference of Cubes Explained
The difference of cubes refers to a specific type of expression where one cubed term is subtracted from another. When we come across expressions like \( x^3 - 27 \), we can treat them as the difference of two cubes. This is a special algebraic form with a distinct factorization method. Let's break down the formula for the difference of cubes:Given two cubes, say \( a^3 \) and \( b^3 \), the difference is expressed in a formula as:\[(a^3 - b^3) = (a - b)(a^2 + ab + b^2)\]
Steps to Factor a Difference of Cubes:
- Identify the terms that are perfect cubes in your expression.
- For \( x^3 - 27 \), we recognize that \( x \) and \( 3 \) are our bases because \( 27 \) is \( 3^3 \).
- Inserting these into the formula, we get \((x - 3)(x^2 + 3x + 9)\).
The Art of Factorization
Factorization is the process of breaking down an algebraic expression into the simplest polynomials that can multiply to give the original expression. It’s a bit like dismantling something complicated into all of its individual pieces so you can see how it was constructed.
Why Factorization is Important:
- It simplifies complex algebraic expressions, making them easier to work with.
- Factorization helps in solving algebraic equations by finding the roots of the polynomial.
- It provides insights into the properties of mathematical relationships and aids in the understanding of polynomial functions.