Math Problem Statement

Graph the rational function f(x) = (2x + 2) / (x + 4). Start by drawing the vertical and horizontal asymptotes. Then plot two points on each piece of the graph. Finally, click on the graph-a-function button.

Solution

The function you are asked to graph is a rational function:

f(x)=2x+2x+4f(x) = \frac{2x + 2}{x + 4}

Step-by-Step Guide for Graphing:

  1. Find Vertical Asymptote: The vertical asymptote occurs where the denominator is zero. Set x+4=0x + 4 = 0, giving us x=4x = -4. So, the vertical asymptote is the vertical line x=4x = -4.

  2. Find Horizontal Asymptote: To determine the horizontal asymptote, compare the degrees of the numerator and denominator. Both the numerator and denominator have a degree of 1. The horizontal asymptote is found by dividing the leading coefficients of the terms: 21=2\frac{2}{1} = 2 So, the horizontal asymptote is y=2y = 2.

  3. Plot Points: Select points on either side of the vertical asymptote to understand the curve's shape.

    • For x=5x = -5:
      f(5)=2(5)+25+4=10+21=81=8f(-5) = \frac{2(-5) + 2}{-5 + 4} = \frac{-10 + 2}{-1} = \frac{-8}{-1} = 8 So, the point (5,8)(-5, 8) lies on the curve.

    • For x=0x = 0:
      f(0)=2(0)+20+4=24=12f(0) = \frac{2(0) + 2}{0 + 4} = \frac{2}{4} = \frac{1}{2} So, the point (0,0.5)(0, 0.5) lies on the curve.

  4. Sketch the Graph: Now that you have the vertical asymptote x=4x = -4, horizontal asymptote y=2y = 2, and some points, sketch the curve approaching these asymptotes.

Would you like any additional details or clarifications?

Here are 5 related questions to deepen your understanding:

  1. How do you find slant asymptotes for rational functions?
  2. Can a rational function have more than one vertical asymptote?
  3. What happens to the function near the vertical asymptote?
  4. How do you determine if a rational function crosses its horizontal asymptote?
  5. How can holes occur in the graph of a rational function?

Tip: Always check if a rational function can be simplified further by factoring both the numerator and denominator before analyzing asymptotes.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Rational Functions
Asymptotes
Graphing Functions

Formulas

f(x) = (2x + 2) / (x + 4)
Vertical Asymptote: x = -4
Horizontal Asymptote: y = 2

Theorems

Concept of Asymptotes for Rational Functions

Suitable Grade Level

Grades 10-12