Determining The End Behavior Of The Function F(x) = (x^2 - 100) / (x^2 - 3x - 4)

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In the captivating realm of mathematics, analyzing the end behavior of functions is a crucial aspect of understanding their overall characteristics and graphical representation. Specifically, we will delve into the fascinating realm of rational functions and meticulously dissect the end behavior of the function f(x) = (x^2 - 100) / (x^2 - 3x - 4). This exploration will equip you with the tools to confidently determine how a function behaves as the input variable, x, ventures towards the distant reaches of positive and negative infinity. In order to accurately describe the end behavior, it's essential to understand the fundamental concepts that govern the behavior of rational functions, especially as x takes on extremely large positive or negative values.

Deciphering End Behavior: A Foundation

Before we dive into the specifics of our function, let's first lay the groundwork by establishing a firm understanding of what end behavior signifies. Essentially, the end behavior of a function provides valuable insights into the function's long-term trends – how the function's output values, often denoted as f(x) or y, behave as the input values, x, become exceptionally large (approaching positive infinity, denoted as ∞) or exceptionally small (approaching negative infinity, denoted as -∞). This analysis is particularly insightful for rational functions, which are defined as the ratio of two polynomials.

The end behavior of a rational function is intricately linked to the degrees of the polynomials that constitute its numerator and denominator. The degree of a polynomial is simply the highest power of the variable within the polynomial expression. For instance, in the polynomial x^2 - 100, the degree is 2, while in the polynomial x^2 - 3x - 4, the degree is also 2. The relationship between these degrees dictates the function's asymptotic behavior, which describes how the function approaches certain lines or values as x tends towards infinity or negative infinity. Grasping these underlying principles will pave the way for a thorough analysis of the given function.

Navigating the Function f(x) = (x^2 - 100) / (x^2 - 3x - 4)

Now, let's turn our attention to the function at hand: f(x) = (x^2 - 100) / (x^2 - 3x - 4). This function is a classic example of a rational function, where both the numerator and denominator are polynomial expressions. The numerator, x^2 - 100, is a quadratic expression, while the denominator, x^2 - 3x - 4, is also a quadratic expression. To effectively determine the end behavior of this function, we need to carefully examine the degrees of these polynomials.

As mentioned earlier, the degree of a polynomial is the highest power of the variable. In both the numerator and denominator of our function, the highest power of x is 2. This crucial observation tells us that the degrees of the numerator and denominator are equal. When the degrees of the numerator and denominator in a rational function are the same, a specific rule governs the function's end behavior. In such cases, the function will approach a horizontal asymptote as x approaches positive or negative infinity. The value of this horizontal asymptote is determined by the ratio of the leading coefficients of the numerator and denominator polynomials.

In our function, the leading coefficient of the numerator (the coefficient of the x^2 term) is 1, and the leading coefficient of the denominator (also the coefficient of the x^2 term) is also 1. Therefore, the ratio of the leading coefficients is 1/1 = 1. This signifies that the function f(x) will approach the horizontal asymptote y = 1 as x approaches either positive or negative infinity. This key finding allows us to pinpoint the correct statement that describes the function's end behavior.

Identifying the Correct Statement

Having meticulously analyzed the function and its components, we are now well-equipped to identify the statement that accurately describes its end behavior. Let's revisit the options presented:

A. The function approaches 0 as x approaches -∞ and ∞. B. The function approaches 1 as x approaches -∞ and ∞.

Based on our analysis, we have established that the function f(x) = (x^2 - 100) / (x^2 - 3x - 4) approaches the horizontal asymptote y = 1 as x approaches both negative infinity and positive infinity. Therefore, option B is the statement that correctly describes the end behavior of the function. The function does not approach 0; instead, it converges towards the value of 1 as x becomes extremely large in either the positive or negative direction. This conclusion aligns perfectly with our understanding of rational functions and their asymptotic behavior.

Factoring for a Deeper Dive and Potential Vertical Asymptotes

While we have successfully determined the end behavior by focusing on the degrees and leading coefficients, it's worth taking a moment to explore the factored form of the function. Factoring the numerator and denominator can reveal valuable insights into the function's behavior, such as the presence of any vertical asymptotes or holes.

The numerator, x^2 - 100, can be factored as a difference of squares: (x - 10)(x + 10). The denominator, x^2 - 3x - 4, can be factored as (x - 4)(x + 1). Therefore, the factored form of the function is:

f(x) = [(x - 10)(x + 10)] / [(x - 4)(x + 1)]

This factored form reveals that the function has vertical asymptotes at x = 4 and x = -1, as these are the values of x that make the denominator equal to zero. These vertical asymptotes further contribute to the function's overall behavior and graphical representation. However, they do not influence the end behavior, which is primarily dictated by the degrees and leading coefficients of the polynomials.

Conclusion: Mastering End Behavior Analysis

In conclusion, by carefully examining the degrees of the polynomials in the numerator and denominator, we have successfully determined that the function f(x) = (x^2 - 100) / (x^2 - 3x - 4) approaches 1 as x approaches both negative infinity and positive infinity. This understanding of end behavior is a fundamental concept in the study of functions and is crucial for comprehending their long-term trends and graphical representations. This thorough analysis has not only provided the correct answer but has also deepened our understanding of the underlying principles that govern the behavior of rational functions.

Understanding the end behavior of functions, especially rational functions, is a critical skill in mathematics. By focusing on the degrees of the numerator and denominator polynomials, you can accurately predict how the function will behave as x approaches infinity. This knowledge is not only valuable for solving specific problems but also for gaining a deeper appreciation of the rich and intricate world of mathematical functions.

In mathematics, analyzing the end behavior of functions, especially rational functions, is a crucial aspect of understanding their overall characteristics and graphical representation. This guide provides a comprehensive explanation of how to determine the end behavior of the rational function f(x) = (x^2 - 100) / (x^2 - 3x - 4), equipping you with the tools to confidently analyze similar functions.

What is End Behavior?

The end behavior of a function describes how the function's output values (y-values) behave as the input values (x-values) become extremely large (approaching positive infinity, ∞) or extremely small (approaching negative infinity, -∞). For rational functions, which are ratios of polynomials, the end behavior is primarily determined by the degrees of the polynomials in the numerator and denominator.

Key Concepts: Degrees and Leading Coefficients

The degree of a polynomial is the highest power of the variable in the polynomial expression. For example, the degree of x^2 - 100 is 2, and the degree of x^3 + 2x - 1 is 3.

The leading coefficient of a polynomial is the coefficient of the term with the highest power of the variable. In x^2 - 100, the leading coefficient is 1 (the coefficient of x^2). In 2x^3 + x, the leading coefficient is 2.

Rules for End Behavior of Rational Functions

The end behavior of a rational function is dictated by the relationship between the degrees of the numerator and denominator polynomials:

  • Case 1: Degree of Numerator < Degree of Denominator: The function approaches 0 as x approaches ±∞. In this case, the x-axis (y = 0) is a horizontal asymptote.
  • Case 2: Degree of Numerator = Degree of Denominator: The function approaches a horizontal asymptote at y = (leading coefficient of numerator) / (leading coefficient of denominator) as x approaches ±∞.
  • Case 3: Degree of Numerator > Degree of Denominator: The function does not have a horizontal asymptote. It may have a slant (oblique) asymptote or approach ±∞. We will not delve into slant asymptotes in this guide, but focus on cases 1 and 2.

Analyzing f(x) = (x^2 - 100) / (x^2 - 3x - 4)

Let's apply these rules to our function, f(x) = (x^2 - 100) / (x^2 - 3x - 4):

  1. Identify the degrees: The numerator (x^2 - 100) has a degree of 2, and the denominator (x^2 - 3x - 4) also has a degree of 2.
  2. Compare the degrees: The degrees of the numerator and denominator are equal (Case 2).
  3. Find the leading coefficients: The leading coefficient of the numerator (x^2 - 100) is 1, and the leading coefficient of the denominator (x^2 - 3x - 4) is also 1.
  4. Determine the horizontal asymptote: Since the degrees are equal, the horizontal asymptote is y = (leading coefficient of numerator) / (leading coefficient of denominator) = 1/1 = 1.
  5. State the end behavior: Therefore, the function f(x) approaches 1 as x approaches both positive and negative infinity.

Factoring for Additional Insights (Optional)

While we've determined the end behavior, factoring the function can provide further understanding. The factored form of f(x) is:

f(x) = [(x - 10)(x + 10)] / [(x - 4)(x + 1)]

This reveals:

  • Vertical asymptotes: at x = 4 and x = -1 (where the denominator equals zero).
  • Zeros (x-intercepts): at x = 10 and x = -10 (where the numerator equals zero).

However, these factors do not affect the end behavior, which is solely determined by the degrees and leading coefficients.

The Correct Answer

Based on our analysis, the correct statement describing the end behavior of f(x) is:

  • The function approaches 1 as x approaches -∞ and ∞.

Conclusion: Mastering End Behavior Analysis

Analyzing the end behavior of rational functions is a crucial skill in mathematics. By understanding the relationship between the degrees of the numerator and denominator polynomials, you can accurately predict how the function will behave as x approaches infinity. This guide has demonstrated a step-by-step approach to analyzing end behavior, providing you with the knowledge and tools to tackle similar problems with confidence.

This detailed explanation has not only identified the correct answer but also provided a thorough understanding of the underlying mathematical principles. Remember to always focus on the degrees and leading coefficients when determining the end behavior of rational functions. With practice, you'll become proficient in this essential skill.

In mathematics, understanding the end behavior of a function is essential for grasping its overall characteristics and graph. This article focuses on how to determine the correct statement describing the end behavior of the rational function f(x) = (x^2 - 100) / (x^2 - 3x - 4). We will explore the concepts and steps necessary to analyze such functions and accurately describe their behavior as x approaches positive and negative infinity.

Understanding End Behavior in the Context of Rational Functions

The end behavior of a function refers to its behavior as the input value, x, approaches positive infinity (∞) or negative infinity (-∞). For rational functions, which are functions expressed as the ratio of two polynomials, the end behavior is primarily governed by the relationship between the degrees of the polynomials in the numerator and the denominator. The degree of a polynomial is the highest power of the variable within the polynomial.

When analyzing end behavior, we are essentially asking: What value does the function's output, f(x), approach as x becomes extremely large (positive or negative)? This information helps us understand the long-term trend of the function and provides crucial insights into its graphical representation. Specifically, the existence of horizontal asymptotes, which the function approaches as x tends towards infinity, is directly related to the end behavior of the rational function.

Analyzing the Given Function: f(x) = (x^2 - 100) / (x^2 - 3x - 4)

Let's consider the given function: f(x) = (x^2 - 100) / (x^2 - 3x - 4). This is a rational function because it is a ratio of two polynomials: x^2 - 100 in the numerator and x^2 - 3x - 4 in the denominator. To determine the end behavior, we need to compare the degrees of these polynomials.

The numerator, x^2 - 100, is a quadratic polynomial, meaning its highest power of x is 2. Therefore, the degree of the numerator is 2. Similarly, the denominator, x^2 - 3x - 4, is also a quadratic polynomial, with the highest power of x being 2. Thus, the degree of the denominator is also 2. Since the degrees of the numerator and the denominator are equal, we can apply a specific rule to determine the end behavior.

When the degrees of the numerator and denominator are equal, the function will approach a horizontal asymptote as x approaches positive or negative infinity. The value of this horizontal asymptote is determined by the ratio of the leading coefficients of the polynomials. The leading coefficient is the coefficient of the term with the highest power of x. In our function, the leading coefficient of the numerator is 1 (the coefficient of x^2), and the leading coefficient of the denominator is also 1 (the coefficient of x^2). Therefore, the horizontal asymptote is y = 1/1 = 1. This implies that as x approaches positive or negative infinity, the function f(x) will approach the value 1.

Identifying the Correct Statement Describing End Behavior

Now that we have analyzed the function and determined its end behavior, we can identify the correct statement from the given options. The possible statements are typically phrased to describe what the function does as x approaches positive and negative infinity. Based on our analysis, we know that the function approaches 1 as x approaches both positive and negative infinity. Therefore, the correct statement would be:

  • The function approaches 1 as x approaches -∞ and ∞.

This statement accurately reflects the end behavior we determined by comparing the degrees of the polynomials and calculating the horizontal asymptote. Choosing this statement demonstrates a solid understanding of how to analyze rational functions and describe their behavior at extreme values of x.

The Importance of Factoring and Vertical Asymptotes (Further Exploration)

While analyzing the degrees and leading coefficients is sufficient for determining the end behavior, it's worth noting that factoring the numerator and denominator can provide additional insights into the function's characteristics. Factoring can reveal vertical asymptotes, which occur at values of x that make the denominator equal to zero, and zeros (x-intercepts), which occur at values of x that make the numerator equal to zero. Factoring can reveal the function's vertical asymptotes and zeros, but they do not directly impact the end behavior. The end behavior is primarily governed by the degrees of the polynomials.

Conclusion: Mastering End Behavior Analysis for Rational Functions

In conclusion, determining the correct statement describing the end behavior of a rational function involves analyzing the degrees of the polynomials in the numerator and denominator. When the degrees are equal, the function approaches a horizontal asymptote, which can be found by taking the ratio of the leading coefficients. This analysis allows us to accurately describe how the function behaves as x approaches positive and negative infinity. By understanding these concepts, you can confidently analyze a wide range of rational functions and accurately describe their end behavior, a critical skill in mathematical analysis and function comprehension.

The ability to determine the end behavior of rational functions is a fundamental skill in mathematics. By mastering the concepts discussed in this guide, you will be well-equipped to analyze the behavior of these functions and select the correct statement describing their end behavior with confidence.