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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 97a

Simplify each rational expression. Assume all variable expressions represent positive real numbers. (Hint: Use factoring and divide out any common factors as a first step.) [4(x2- 1)3 + 8x(x2-1)4] / [16(x2-1)3]

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1
Start by examining the given rational expression: \(\frac{4(x^2 - 1)^3 + 8x(x^2 - 1)^4}{16(x^2 - 1)^3}\). Notice that both the numerator and denominator contain powers of the expression \((x^2 - 1)\).
Factor out the greatest common factor (GCF) from the numerator. The GCF is \$4(x^2 - 1)^3$, so rewrite the numerator as \(4(x^2 - 1)^3 \left[1 + 2x(x^2 - 1)\right]\).
Rewrite the entire expression using the factored numerator: \(\frac{4(x^2 - 1)^3 \left[1 + 2x(x^2 - 1)\right]}{16(x^2 - 1)^3}\).
Cancel out the common factors in the numerator and denominator. Since both have \$4(x^2 - 1)^3$, divide numerator and denominator by this term to simplify the expression to \(\frac{1 + 2x(x^2 - 1)}{4}\).
Finally, expand the term \$2x(x^2 - 1)\( in the numerator to get \)2x^3 - 2x$, then write the simplified expression as \(\frac{1 + 2x^3 - 2x}{4}\). This is the simplified form of the original rational expression.

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Key Concepts

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

Factoring Polynomials

Factoring involves rewriting a polynomial as a product of simpler polynomials or expressions. Recognizing common patterns like difference of squares or factoring out the greatest common factor helps simplify expressions and is essential before performing operations like division.
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