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

viniterranova

(x +1) / (2-x) < 4

  • 2 years ago
  • 2 years ago

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

    first find when (x+1)/(2-x)=4 or is undefined

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

    you will need these values to solve the inequality

    • 2 years ago
  3. viniterranova
    Best Response
    You've already chosen the best response.
    Medals 0

    • 2 years ago
    1 Attachment
  4. viniterranova
    Best Response
    You've already chosen the best response.
    Medals 0

    May this help you.

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

    yes, i know that is the question, but it is important that you solve the equation (x+1)/(2-x)=4 before you solve (x+1)/(2-x)<4

    • 2 years ago
  6. viniterranova
    Best Response
    You've already chosen the best response.
    Medals 0

    Sorry....but may u do it?

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

    (x+1)/(2-x)=4 x+1=4(2-x) x+1=8-4x 5x=7 x=7/5 we also must know when (x+1)/(2-x)=4 is undefined it is undefined at x=2, because the denominator 2-x=0

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

    now we can split the number line up into 3 intervals using these 2 numbers

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

    first we will simplify the rational inequality

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

    well i guess that's not necessary in this case, but usually you want to get 0 on one side of the inequality

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

    we have the values we will use to form our intervals, x=2, x=7/5 this splits the domain of the function into the following intervals: (-infinity, 7/5), (7/5, 2), (2, infinity)

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

    we will pick a value at random from these intervals and see if it is less than 4. if it is, the entire interval is part of the solution

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

    from the first interval we can use x=0 (0+1)/(2-0)<4? 1/2<4? TRUE x<7/5 is part of the solution

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

    next we will pick the value 8/5 from the 2nd interval (8/5+1)/(2-8/5)<4? (13/5)/(2/5)<4? 13/2<4? FALSE, this is not part of solution

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

    from 3rd interval we can use x=3 (3+1)/(2-3)<4? 4/-1<4? -4<4? TRUE x>2 is part of solution so entire solution is x<7/5 or x>2 now you see why we had to solve the related equation

    • 2 years ago
  16. viniterranova
    Best Response
    You've already chosen the best response.
    Medals 0

    Thanks for the answer

    • 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.