Quantcast

A community for students. Sign up today!

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

maddypeoples

  • 2 years ago

Using the First Derivative Test, find any local extema for f(x)= x^2+25/x

  • This Question is Open
  1. richyw
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 2

    well take the first derivative\[f'(x)=2x-\frac{25}{x^2}\]set this equal to zero to find extrema. \[2x=\frac{25}{x^2}\]\[2x^3=25\]\[x^3=\frac{25}{2}\]\[x=\sqrt[3]{\frac{25}{2}}\]\[x=\frac{5^{2}{3}}{\sqrt[3]{2}}\]

  2. UnkleRhaukus
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    im not sure about you last line @richyw , once you have found x , substitute back into f to find f(x) and hence ( x , f(x) )

  3. richyw
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 2

    right, sorrt that was a typo. should be \(5^{3/2}\) if I recall correctly...

  4. richyw
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 2

    I hope they caught that because I would never leave 75 written as \(5^23\) haha

  5. Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Ask a Question
Find more explanations on OpenStudy

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...

23

  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.