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# Graphing Rational Functions: Identifying the Correct One

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#### Graphing Rational Functions: Identifying the Correct One

Have you ever found yourself gazing at a graph of a rational function and wondering which one is the correct representation? Look no further, as we delve into the fascinating world of graphing rational functions. With an understanding of their characteristics, we can identify the correct graph with confidence. Whether it’s recognizing asymptotes, finding intercepts, or analyzing end behavior, this article will equip you with the necessary tools to navigate through the maze of rational functions. Get ready to unlock the secrets behind these intricate graphs and unravel their mysteries. So, let’s dive in and discover how to identify the correct graph for any given rational function.

Graphing Rational Functions: Identifying the Correct One

Rational functions are a type of mathematical function that can be represented as the ratio of two polynomial functions. These functions can have various forms and characteristics, making it challenging to identify the correct graph. In this article, we will explore how to identify the graph of a rational function accurately.

To begin with, let’s understand the general form of a rational function:

𝑓(𝑥) = 𝑝(𝑥) / 𝑞(𝑥)

Here, 𝑝(𝑥) and 𝑞(𝑥) are polynomial functions with real coefficients, and 𝑞(𝑥) ≠ 0.

Now, let’s discuss some key steps to help us correctly identify the graph of a rational function:

1. Determine Restrictions:
Firstly, we need to find any restrictions on our rational function. These occur when the denominator (𝑞(𝑥)) equals zero since division by zero is undefined. To find these restrictions, we set 𝑞(𝑥) = 0 and solve for 𝑥.

2. Find Vertical Asymptotes:
Vertical asymptotes are vertical lines that represent values where our rational function approaches positive or negative infinity as 𝑥 approaches certain values (excluding any restrictions). To find these vertical asymptotes, we factorize both numerator and denominator polynomials and examine any common factors that cancel out.

3. Locate Horizontal Asymptotes:
Horizontal asymptotes reveal how our rational function behaves as 𝑥 moves towards positive or negative infinity. We can determine them by comparing the degrees of both numerator and denominator polynomials.

– If the degree of the numerator is less than the degree of the denominator (deg(𝑝(𝑥)) < deg(𝑞(𝑥))), then there is a horizontal asymptote at 𝑦 = 0 (the x-axis). - If the degree of the numerator is equal to the degree of the denominator (deg(𝑝(𝑥)) = deg(𝑞(𝑥))), then there is a horizontal asymptote at 𝑦 = ratio of leading coefficients. - If the degree of the numerator is greater than the degree of the denominator (deg(𝑝(𝑥)) > deg(𝑞(𝑥))), then there are no horizontal asymptotes, but there may be slant or oblique asymptotes.

4. Analyze Intercepts:
Next, let’s examine any intercepts our function may have. We find x-intercepts by setting 𝑝(𝑥) = 0 and solving for 𝑥. To find y-intercepts, we set 𝑥 = 0 and evaluate 𝑓(0) = 𝑝(0) / 𝑞(0).