Math Problem Statement

Find a rational function that satisfies the given conditions. Answers may​ vary, but try to give the simplest answer possible.

Vertical asymptotes

xequals=negative 1−1​,

xequals=77​;

​x-intercept

​(22​,0)

Question content area bottom

Part 1

A.

​f(x)equals=StartFraction x plus 2 Over x squared minus 6 x minus 7 EndFractionx+2x2−6x−7

B.

​f(x)equals=StartFraction x minus 2 Over x squared plus 6 x plus 7 EndFractionx−2x2+6x+7

C.

​f(x)equals=StartFraction x minus 2 Over x squared minus 6 x minus 7 EndFractionx−2x2−6x−7

D.

​f(x)equals=StartFraction x plus 2 Over x squared minus 6 x plus 7 EndFraction

Solution

We are asked to find a rational function that satisfies the following conditions:

  • Vertical asymptotes: x=1x = -1 and x=7x = 7
  • x-intercept: (2,0)(2, 0)

Step 1: General form of a rational function

A rational function with vertical asymptotes at x=1x = -1 and x=7x = 7 would have a denominator of the form (x+1)(x7)(x + 1)(x - 7), because the denominator must be zero at x=1x = -1 and x=7x = 7.

Thus, the general form of the function can be written as: f(x)=N(x)(x+1)(x7)f(x) = \frac{N(x)}{(x + 1)(x - 7)} where N(x)N(x) is the numerator that we will determine next.

Step 2: Determining the numerator

We are also given that the function has an x-intercept at (2,0)(2, 0), meaning f(2)=0f(2) = 0. This implies that x2x - 2 must be a factor of the numerator N(x)N(x). Therefore, we have: N(x)=x2N(x) = x - 2

Step 3: Final function

Thus, the simplest rational function that satisfies the given conditions is: f(x)=x2(x+1)(x7)f(x) = \frac{x - 2}{(x + 1)(x - 7)}

Step 4: Match with options

Now, comparing this with the provided options:

  • Option A: f(x)=x+2x26x7f(x) = \frac{x + 2}{x^2 - 6x - 7} — incorrect, wrong numerator.
  • Option B: f(x)=x2x2+6x+7f(x) = \frac{x - 2}{x^2 + 6x + 7} — incorrect, wrong denominator.
  • Option C: f(x)=x2x26x7f(x) = \frac{x - 2}{x^2 - 6x - 7} — correct, because x26x7x^2 - 6x - 7 factors into (x+1)(x7)(x + 1)(x - 7).
  • Option D: f(x)=x+2x26x+7f(x) = \frac{x + 2}{x^2 - 6x + 7} — incorrect, wrong numerator and denominator.

The correct answer is Option C: f(x)=x2x26x7f(x) = \frac{x - 2}{x^2 - 6x - 7}.

Would you like more details or have any questions?


Here are 5 related questions:

  1. How do you determine the vertical asymptotes of a rational function?
  2. How can you find the x-intercepts of a rational function?
  3. What is the significance of factoring the denominator in rational functions?
  4. How do horizontal asymptotes differ from vertical asymptotes in rational functions?
  5. Can a rational function have more than one x-intercept?

Tip: Always check the factors of both the numerator and denominator to determine intercepts and asymptotes of rational functions.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Rational Functions
Vertical Asymptotes
x-intercepts

Formulas

f(x) = N(x) / D(x)
Factoring quadratic expressions: ax^2 + bx + c

Theorems

The Rational Root Theorem
Properties of Asymptotes in Rational Functions

Suitable Grade Level

Grades 10-12