Math Problem Statement

The figure shows the graph of a rational function f. It has vertical asymptotes x = 2 and x = -3, and a horizontal asymptote y = 2. The graph has x-intercepts -4 and 1, and it passes through the point (-1, 2). Choose the appropriate form of f(x) and write the equation in simplest form.

Solution

Let's break down the problem to find the appropriate form of the function f(x)f(x).

Given information:

  1. Vertical asymptotes at x=2x = 2 and x=3x = -3.
  2. Horizontal asymptote at y=2y = 2.
  3. x-intercepts at x=4x = -4 and x=1x = 1.
  4. The graph passes through the point (1,2)(-1, 2).

Step-by-step solution:

  1. Vertical asymptotes:

    • These occur where the denominator of a rational function equals zero.
    • Thus, the factors (x2)(x - 2) and (x+3)(x + 3) should be in the denominator.
  2. Horizontal asymptote:

    • The horizontal asymptote is y=2y = 2, which suggests the degree of the numerator and denominator must be the same.
    • To have a horizontal asymptote of y=2y = 2, the leading coefficient of the numerator must be 2 times that of the denominator.
  3. x-intercepts:

    • These occur when the numerator equals zero.
    • The x-intercepts are at x=4x = -4 and x=1x = 1, so the numerator must include the factors (x+4)(x + 4) and (x1)(x - 1).
  4. Equation form:

    • The equation should resemble the third option: f(x)=a(xb)(xc)(xd)(xe)f(x) = \frac{a (x - b)(x - c)}{(x - d)(x - e)}
    • Substituting the known intercepts and asymptotes: f(x)=a(x+4)(x1)(x2)(x+3)f(x) = \frac{a (x + 4)(x - 1)}{(x - 2)(x + 3)}
  5. Determine aa:

    • Since the function passes through the point (1,2)(-1, 2), substitute x=1x = -1 and f(x)=2f(x) = 2 to find aa: 2=a(1+4)(11)(12)(1+3)2 = \frac{a (-1 + 4)(-1 - 1)}{(-1 - 2)(-1 + 3)} Simplifying: 2=a(3)(2)(3)(2)2 = \frac{a(3)(-2)}{(-3)(2)} 2=6a62 = \frac{-6a}{-6} 2=a2 = a

Final equation:

f(x)=2(x+4)(x1)(x2)(x+3)f(x) = \frac{2(x + 4)(x - 1)}{(x - 2)(x + 3)}

Let me know if you would like more details, and here are 5 related questions:

  1. How do you determine horizontal asymptotes in rational functions?
  2. What conditions lead to a vertical asymptote in a rational function?
  3. How can you find the x-intercepts of a rational function?
  4. What happens to the graph of a rational function at points where the numerator equals zero?
  5. Why is the horizontal asymptote affected by the degrees of the numerator and denominator?

Tip: Always check for points where the function is undefined to determine vertical asymptotes!

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Math Problem Analysis

Mathematical Concepts

Rational functions
Asymptotes
x-intercepts
Factorization

Formulas

Vertical asymptotes occur where the denominator equals zero.
Horizontal asymptote for a rational function occurs when degrees of numerator and denominator are equal.

Theorems

The behavior of rational functions at vertical and horizontal asymptotes
Zeros of rational functions and x-intercepts

Suitable Grade Level

Grades 10-12