Chapter 6: Problem 18
For Problems \(13-44\), factor each polynomial completely. Indicate any that are not factorable using integers. Don't forget to look for a common monomial factor first. (Objective 1) $$ 8 x^{2}-32 y^{2} $$
Short Answer
Expert verified
The completely factored form is \(8(x - 2y)(x + 2y)\).
Step by step solution
01
Identify a Common Monomial Factor
First, identify if there is a common factor for both terms in the polynomial. The terms are \(8x^2\) and \(-32y^2\). The common factor here is 8, as it divides both coefficients (8 and 32). Thus, we can factor out 8 from the polynomial.
02
Factor Out the Common Monomial
Factor the common monomial, 8, from both terms in the polynomial: \[8x^2 - 32y^2 = 8(x^2 - 4y^2)\].
03
Check for Difference of Squares
Now, look inside the parentheses. Notice that \(x^2 - 4y^2\) is a difference of squares. Recall that a difference of squares is given by the formula \(a^2 - b^2 = (a - b)(a + b)\). Here, \(a = x\) and \(b = 2y\).
04
Apply the Difference of Squares Formula
Apply the formula to factor the expression further: \[x^2 - 4y^2 = (x - 2y)(x + 2y)\].
05
Write the Completely Factored Form
Combine the factored terms with the original monomial factor from Step 1 to write the completely factored form of the polynomial: \[8(x - 2y)(x + 2y)\].
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.
Difference of Squares
In algebra, the concept of "difference of squares" is a valuable tool for factoring certain types of quadratic expressions. It applies specifically to polynomials that fit the pattern of two perfect squares being subtracted. To recognize a difference of squares, look for an expression like \(a^2 - b^2\), where both \(a\) and \(b\) are expressions that, when squared, perfectly match the terms of your polynomial. For example, in \(x^2 - 4y^2\), we identify \(x^2\) as \(a^2\), and \(4y^2\) as \(b^2\) (since \(4y^2 = (2y)^2\)). The factorization of a difference of squares uses a straightforward formula:
- \(a^2 - b^2 = (a - b)(a + b)\)
Common Monomial Factor
Before diving into factoring polynomials through various techniques, it is crucial to look for a "common monomial factor." This method simplifies expressions by reducing coefficients through common divisors. Consider the polynomial \(8x^2 - 32y^2\) as an example. Both terms, \(8x^2\) and \(-32y^2\), share a common factor: 8. Factor it out to simplify the expression. Doing so gives us:
- \(8(x^2 - 4y^2)\)
Factoring Techniques in Algebra
Understanding various "factoring techniques in algebra" is fundamental for manipulating and simplifying mathematical expressions. Different techniques are used depending on the structure of the polynomial.
- Common Monomial Factor: Check for common factors in all terms and factor them out first.
- Difference of Squares: Use when dealing with expressions of the form \(a^2 - b^2\).
- Trinomials: Use techniques such as grouping or applying the quadratic formula in certain cases, though not relevant for a difference of squares.