Question
upstudy study bank question image url

Write an equation for a rational function with the following properties: - Vertical asymptotes at \( x=1 \) and \( x=-4 \) - Zeros ( \( x \)-intercepts) at \( x=-2 \) and \( x=-5 \) - A \( y \)-intercept at \( (0,5) \) Leave your equation in foctored form. \( r(x)=\square \)

Ask by Craig Martinez. in the United States
Mar 12,2025

Upstudy AI Solution

Tutor-Verified Answer

Answer

\( r(x) = -2 \cdot \frac{(x + 2)(x + 5)}{(x - 1)(x + 4)} \)

Solution

We start by writing the rational function in factored form with an unknown constant \( k \): \[ r(x)=k\,\frac{(x+2)(x+5)}{(x-1)(x+4)} \] The vertical asymptotes at \( x=1 \) and \( x=-4 \) come from the factors in the denominator \( (x-1) \) and \( (x+4) \). The zeros at \( x=-2 \) and \( x=-5 \) come from the factors in the numerator \( (x+2) \) and \( (x+5) \). Next, to determine \( k \), we use the \( y \)-intercept \( (0,5) \) by plugging in \( x=0 \): \[ r(0)=k\,\frac{(0+2)(0+5)}{(0-1)(0+4)} = k\,\frac{2\cdot5}{(-1)\cdot4} = k\,\frac{10}{-4} = -\frac{5k}{2} \] Since \( r(0)=5 \), we have: \[ -\frac{5k}{2}=5 \] Multiply both sides by 2: \[ -5k=10 \] Divide both sides by \(-5\): \[ k=-2 \] Substitute \( k=-2 \) back into the function: \[ r(x)=-2\,\frac{(x+2)(x+5)}{(x-1)(x+4)} \] Thus, the equation for the rational function in factored form is: \[ r(x)=-2\,\frac{(x+2)(x+5)}{(x-1)(x+4)} \]

Answered by UpStudy AI and reviewed by a Professional Tutor

error msg
Explain
Simplify this solution

The Deep Dive

To construct a rational function \( r(x) \) based on the given properties, we can start by writing the factors for the vertical asymptotes and the zeros. The vertical asymptotes at \( x=1 \) and \( x=-4 \) indicate the function will have factors in the denominator: \[ (x - 1)(x + 4) \] The zeros at \( x=-2 \) and \( x=-5 \) indicate that the function will have factors in the numerator: \[ (x + 2)(x + 5) \] Now, putting these factors together, we have: \[ r(x) = \frac{(x + 2)(x + 5)}{(x - 1)(x + 4)} \] Next, we need to ensure that the \( y \)-intercept is \( (0, 5) \). To find the \( y \)-intercept, we can substitute \( x = 0 \) into our function: \[ r(0) = \frac{(0 + 2)(0 + 5)}{(0 - 1)(0 + 4)} = \frac{(2)(5)}{(-1)(4)} = \frac{10}{-4} = -\frac{5}{2} \] This gives us \( -\frac{5}{2} \) at \( x=0 \). To adjust our function to achieve a \( y \)-intercept of 5, we need to introduce a constant \( k \) in the numerator: \[ r(x) = k \cdot \frac{(x + 2)(x + 5)}{(x - 1)(x + 4)} \] We want \( r(0) = 5 \): \[ 5 = k \cdot \left(-\frac{5}{2}\right) \Rightarrow k = -2 \] So, we multiply through by -2: \[ r(x) = -2 \cdot \frac{(x + 2)(x + 5)}{(x - 1)(x + 4)} \] Thus, the final rational function in factored form is: \[ r(x) = \frac{-2(x + 2)(x + 5)}{(x - 1)(x + 4)} \]

Try Premium now!
Try Premium and ask Thoth AI unlimited math questions now!
Maybe later Go Premium
Study can be a real struggle
Why not UpStudy it?
Select your plan below
Premium

You can enjoy

Start now
  • Step-by-step explanations
  • 24/7 expert live tutors
  • Unlimited number of questions
  • No interruptions
  • Full access to Answer and Solution
  • Full Access to PDF Chat, UpStudy Chat, Browsing Chat
Basic

Totally free but limited

  • Limited Solution
Welcome to UpStudy!
Please sign in to continue the Thoth AI Chat journey
Continue with Email
Or continue with
By clicking “Sign in”, you agree to our Terms of Use & Privacy Policy