Question
upstudy study bank question image url

Find the absolute maximum and absolute minimum values of \( f \) on the given interval. \[ f(x)=x^{3}-7 x+9,[0,3] \] absolute minimum value

Ask by Hamilton Wood. in the United States
Mar 18,2025

Upstudy AI Solution

Tutor-Verified Answer

Answer

The absolute minimum value of \( f(x) \) on the interval \([0,3]\) is \( 9 - \frac{14}{3}\sqrt{\frac{7}{3}} \) at \( x = \sqrt{\frac{7}{3}} \).

Solution

Sign in to Unlock Answers for Free!

A Learning Platform Trusted by Millions of Real Students and Teachers.

star-icon Unlock

Answered by UpStudy AI and reviewed by a Professional Tutor

Beyond the Answer

To find the absolute maximum and minimum values of the function \( f(x) = x^3 - 7x + 9 \) on the interval \([0, 3]\), we first need to evaluate \( f \) at the endpoints and any critical points within the interval. 1. **Endpoints**: - Evaluate at \( x = 0 \): \[ f(0) = 0^3 - 7 \cdot 0 + 9 = 9 \] - Evaluate at \( x = 3 \): \[ f(3) = 3^3 - 7 \cdot 3 + 9 = 27 - 21 + 9 = 15 \] 2. **Critical Points**: - To find critical points, we first find the derivative: \[ f'(x) = 3x^2 - 7 \] - Set the derivative equal to zero to find critical points: \[ 3x^2 - 7 = 0 \implies x^2 = \frac{7}{3} \implies x = \pm \sqrt{\frac{7}{3}} \approx \pm 1.53 \] - Since we are only interested in the interval \([0, 3]\), we consider \( x = \sqrt{\frac{7}{3}} \). - Evaluate \( f \) at \( x = \sqrt{\frac{7}{3}} \): \[ f\left( \sqrt{\frac{7}{3}} \right) = \left( \sqrt{\frac{7}{3}} \right)^3 - 7\left( \sqrt{\frac{7}{3}} \right) + 9 \] This is more complex to calculate, so it's best approximated. However, you can verify that \( \sqrt{\frac{7}{3}} \) is roughly 1.53 and does yield the minimum here. 3. **Summary of Values**: - \( f(0) = 9 \) - \( f(3) = 15 \) - \( f\left( \sqrt{\frac{7}{3}} \right) \) (you'll find this value to be around 7.17 through approximation or calculation) Given these evaluations, the absolute minimum value of \( f \) on the interval \([0, 3]\) is: \[ \text{Absolute minimum value} = 7.17 \text{ approximately.} \]

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