A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • one year ago

Will medal and fan Find the maximum or minimum of the following quadratic function: y = -2x2 + 4x - 1. A. -1 B. 0 C. 1 D. 4

  • This Question is Closed
  1. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I assume you mean -2x^2?

  2. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    y= -2x^2+4x-1

  3. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Are you familiar with the quadratic formula?

  4. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    yeah

  5. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    What you can do here is use the first bit of the quadratic formula (-b/2a) which will find you the x value of the vertex. Then you simply plug that x value back into your original equation to find the y value of the max / min. Since this function starts with -2, you know that it opens downwards so you will be finding a maximum.

  6. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    (-b/2a) or (-4/4) = (-1). This is the x value of the maximum. Plugging this back into the equation... -2(-1)^2 + 4(-1) - 1 = -2(1) - 4 - 1 = -2 - 4 - 1 or -7. Therefore we know the y value of the maximum is at -7. Seeing as -7 isn't one of your answers, I'm going to assume that the question simply wants you to find the x value of the maximum - that is, only do the first bit of all of this. :) Hope I helped!

  7. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    so the answer would be -1?

  8. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Yes, it looks as though the answer would be -1. The question is slightly ambiguous in its wording, but since this function has a maximum at (-1,-7), -1 is the only coordinate that has a matching answer.

  9. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Thank you for helping me

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

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy

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.