Quantcast

Got Homework?

Connect with other students for help. It's a free community.

  • across
    MIT Grad Student
    Online now
  • laura*
    Helped 1,000 students
    Online now
  • Hero
    College Math Guru
    Online now

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

moneysotrue Group Title

Given: f'(x)=4x^3+4x+6. How many points of inflection will the graph of f(x) have?

  • 2 years ago
  • 2 years ago

  • This Question is Closed
  1. Denebel Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    Find the second derivative... find the derivative of this (since this equation is already the first derivative) and set it equal to 0.. that will be where your point(s) of inflection will be.

    • 2 years ago
  2. moneysotrue Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    for my second derivative i got f"(x)=12x^2+4 but I dont think there will be any points am I correct?

    • 2 years ago
  3. Denebel Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    If you set your second derivative equal to 0, you will get a point.

    • 2 years ago
  4. moneysotrue Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    Should I use the quadratic formula?

    • 2 years ago
  5. Denebel Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    Second derivative = 12x + 4 = 0 12x = -4 x= - 1/3

    • 2 years ago
  6. Denebel Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    So you will have 1 point of inflection. You can check this by integrating the first derivative to find the original function. f(x) would be x^4 + 2x + 6x. Graph this and you will see there is one point of inflection.

    • 2 years ago
  7. moneysotrue Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    No the second derivative would be 12\[x^2\]+4

    • 2 years ago
  8. moneysotrue Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    b/c arent I suppose to subtract 1 from my exponent? each time I take my derivative

    • 2 years ago
  9. Denebel Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    Oops, yes. Oh I see now. I would say no points of inflection

    • 2 years ago
  10. Denebel Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    12x^2 + 4 = 0 x^2 = -1/3 but squares of numbers cannot be negatives

    • 2 years ago
  11. moneysotrue Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    okay thanks! I appreciate the help.

    • 2 years ago
    • Attachments:

See more questions >>>

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.