Math Problem Statement

Find the intercepts and asymptotes. (If an answer does not exist, enter DNE. Enter your asymptotes as a comma-separated list of equations if necessary.) r(x) = 3x2 + 6 x2 − 2x − 3 x-intercept (x, y)

y-intercept (x, y)

vertical asymptote

horizontal asymptote

Solution

We will analyze the rational function r(x)=3x2+6x22x3r(x) = \frac{3x^2 + 6}{x^2 - 2x - 3} to determine its intercepts and asymptotes.

1. Finding the x-intercept:

To find the x-intercept, we set r(x)=0r(x) = 0, which happens when the numerator is zero: 3x2+6=03x^2 + 6 = 0 x^2 = -2 \quad \text{(no real solutions since x^2 cannot be negative).} Result: There are no xx-intercepts (x,y=DNEx, y = \text{DNE}).


2. Finding the y-intercept:

To find the y-intercept, we evaluate r(x)r(x) at x=0x = 0: r(0)=3(0)2+6(0)22(0)3=63=2r(0) = \frac{3(0)^2 + 6}{(0)^2 - 2(0) - 3} = \frac{6}{-3} = -2 Result: The yy-intercept is (0,2)(0, -2).


3. Finding the vertical asymptotes:

Vertical asymptotes occur where the denominator is zero and the numerator is nonzero. Solve for the zeros of the denominator: x22x3=0x^2 - 2x - 3 = 0 Factorize: (x3)(x+1)=0(x - 3)(x + 1) = 0 x=3,x=1x = 3, \quad x = -1 Result: The vertical asymptotes are x=3x = 3 and x=1x = -1.


4. Finding the horizontal asymptote:

For the horizontal asymptote, compare the degrees of the numerator and the denominator:

  • The degree of the numerator (3x2+63x^2 + 6) is 2.
  • The degree of the denominator (x22x3x^2 - 2x - 3) is 2.

When the degrees are equal, the horizontal asymptote is given by the ratio of the leading coefficients: y=leading coefficient of numeratorleading coefficient of denominator=31=3y = \frac{\text{leading coefficient of numerator}}{\text{leading coefficient of denominator}} = \frac{3}{1} = 3 Result: The horizontal asymptote is y=3y = 3.


Final Answers:

  • x-intercept: DNE
  • y-intercept: (0,2)(0, -2)
  • Vertical asymptote: x=3,x=1x = 3, x = -1
  • Horizontal asymptote: y=3y = 3

Would you like further clarification or a graph of the function?

5 Relative Questions:

  1. How do vertical asymptotes influence the behavior of a function near them?
  2. What happens to the graph as xx \to \infty or xx \to -\infty for rational functions?
  3. How do we determine the presence of slant asymptotes instead of horizontal asymptotes?
  4. Why is the numerator important when finding the x-intercept of a rational function?
  5. Can a rational function have more than one horizontal asymptote?

Tip:

Always verify the domain of the function to ensure no points are excluded when solving for intercepts and asymptotes.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Rational Functions
Intercepts
Asymptotes

Formulas

Horizontal asymptote for rational functions: Compare degrees of numerator and denominator
Vertical asymptote: Set denominator equal to zero and solve
x-intercept: Set numerator equal to zero and solve

Theorems

Degree Rule for Horizontal Asymptotes
Definition of Vertical Asymptotes
Zero-Product Property

Suitable Grade Level

Grades 10-12