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Ch. R - Review of Basic Concepts
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063Not the one you use?Change textbook
Chapter 1, Problem 72

Factor each polynomial. See Examples 5 and 6. 9m2n22n19m^2-n^2-2n-1

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Identify the polynomial to factor: \$9m^2 - n^2 - 2n - 1$.
Group the terms involving \(n\) together: \$9m^2 - (n^2 + 2n + 1)$.
Recognize that \(n^2 + 2n + 1\) is a perfect square trinomial, which factors as \((n + 1)^2\).
Rewrite the expression as a difference of squares: \$9m^2 - (n + 1)^2$.
Apply the difference of squares formula: \(a^2 - b^2 = (a - b)(a + b)\), where \(a = 3m\) and \(b = n + 1\), to factor as \((3m - (n + 1))(3m + (n + 1))\).

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Key Concepts

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

Factoring Polynomials

Factoring polynomials involves rewriting a polynomial as a product of simpler polynomials or factors. This process helps simplify expressions and solve equations. Common methods include factoring out the greatest common factor, grouping, and special products like difference of squares.
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Difference of Squares

The difference of squares is a special factoring pattern where an expression of the form a² - b² can be factored into (a - b)(a + b). Recognizing this pattern allows quick factoring of certain quadratic expressions, which is essential for simplifying or solving polynomial equations.
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Rearranging and Grouping Terms

Rearranging terms in a polynomial can reveal factoring opportunities, such as grouping terms to factor by grouping. This technique involves organizing terms to create common factors within groups, making it easier to factor the entire polynomial.
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