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Ch. 3 - Polynomial and Rational Functions
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063Not the one you use?Change textbook
Chapter 4, Problem 33

Match the rational function in Column I with the appropriate description in Column II. Choices in Column II can be used only once. ƒ(x)=(x2-16)/(x+4)
Matching exercise with rational functions in Column I and their unique descriptions in Column II, including intercepts and asymptotes.

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1
Identify the given rational function: \(f(x) = \frac{x^2 - 16}{x + 4}\).
Recognize that the numerator \(x^2 - 16\) is a difference of squares, which can be factored as \(x^2 - 16 = (x - 4)(x + 4)\).
Rewrite the function using the factored form: \(f(x) = \frac{(x - 4)(x + 4)}{x + 4}\).
Simplify the expression by canceling the common factor \((x + 4)\) in numerator and denominator, but note that \(x \neq -4\) because division by zero is undefined. The simplified form is \(f(x) = x - 4\), with a restriction on the domain.
Match the function to the description that corresponds to a linear function with a hole (removable discontinuity) at \(x = -4\) due to the canceled factor.

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Key Concepts

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

Rational Functions

A rational function is a ratio of two polynomials, expressed as f(x) = P(x)/Q(x), where Q(x) ≠ 0. Understanding the form and behavior of rational functions is essential for analyzing their properties such as domain, asymptotes, and simplification.
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Simplification and Factorization

Simplifying rational functions involves factoring polynomials in the numerator and denominator to cancel common factors. This process can reveal removable discontinuities (holes) and simplify the function to a more recognizable form.
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Domain and Discontinuities

The domain of a rational function excludes values that make the denominator zero. Identifying these values helps determine vertical asymptotes or holes, which are points where the function is undefined or discontinuous.
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