Skip to main content
Ch. 3 - Polynomial and Rational Functions
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063Not the one you use?Change textbook
Chapter 4, Problem 61

Graph each rational function. ƒ(x)=(x+1)/(x-4)

Verified step by step guidance
1
Identify the rational function given: \(f(x) = \frac{x+1}{x-4}\).
Determine the vertical asymptote by finding the values of \(x\) that make the denominator zero. Set \(x - 4 = 0\) and solve for \(x\).
Find the horizontal asymptote by comparing the degrees of the numerator and denominator. Since both numerator and denominator are degree 1, the horizontal asymptote is the ratio of the leading coefficients.
Calculate the \(x\)-intercept by setting the numerator equal to zero and solving for \(x\), i.e., solve \(x + 1 = 0\).
Calculate the \(y\)-intercept by evaluating \(f(0)\), which means substituting \(x = 0\) into the function.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
12m
Was this helpful?

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 domain restrictions and behavior of these functions is essential, as they often have asymptotes and discontinuities where the denominator is zero.
Recommended video:
6:04
Intro to Rational Functions

Vertical and Horizontal Asymptotes

Vertical asymptotes occur where the denominator equals zero, indicating values excluded from the domain. Horizontal asymptotes describe the end behavior of the function as x approaches infinity or negative infinity, determined by comparing the degrees of the numerator and denominator polynomials.
Recommended video:
4:48
Determining Horizontal Asymptotes

Graphing Rational Functions

Graphing involves identifying intercepts, asymptotes, and behavior near these lines. Plot key points, analyze limits near asymptotes, and use symmetry or transformations to sketch the curve accurately, providing a visual understanding of the function's behavior.
Recommended video:
8:19
How to Graph Rational Functions