A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

mathmath333

  • one year ago

\(\large \color{black}{\begin{align} &\text{Find the number of integer values } \hspace{.33em}\\~\\ &\dfrac{15x^2+2x+1}{x^2-2x-1}\hspace{.33em}\\~\\ &\text{doesn't satisfy } \hspace{.33em}\\~\\ \end{align}}\)

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

    Hi math, Does that mean the number of integer values, which can not be written in the form:\[\dfrac{15x^2+2x+1}{x^2-2x-1}\]?

  2. mathmath333
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    i mean the number of integer values the expression \(\dfrac{15x^2+2x+1}{x^2-2x-1}\) not take

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

    aha that's right, so we just need to find the range of function

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

    \[y=\dfrac{15x^2+2x+1}{x^2-2x-1}\]find \(x\) in terms of \(y\), find the domain of inverse

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

    @mukushla exact !

  6. mathmath333
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    what u mean by x interms of y

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

    solve the equation . and deal with y as a parameter

  8. Ehsan18
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Separate x i.e. find x = ? and replace y with x afterwards.

  9. mathmath333
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    u mean this http://www.wolframalpha.com/input/?i=solve+y%3D%5Cdfrac%7B15x%5E2%2B2x%2B1%7D%7Bx%5E2-2x-1%7D+for+x

  10. ganeshie8
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    Following mukushla's hint \[\large y=\dfrac{15x^2+2x+1}{x^2-2x-1}\] cross multiplying and rearranging gives \[\large (15-y)\color{red}{x^2}+(2+2y)\color{red}{x}+y+1 = 0\] This is a quadratic in \(\color{red}{x}\) you may use the discriminant to find the domain

  11. mathmath333
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    ok, d=8(y+1)(y-7)

  12. ganeshie8
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    how?

  13. mathmath333
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    from this -> (2+2y)^2-4(15-y)(y+1)

  14. ganeshie8
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    Ohk.. Notice that \(D \ge 0\) for the quadratic equation to make sense in real numbers

  15. mathmath333
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    \(y>=7 ,y<=-1\)

  16. ganeshie8
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    those are the values the given rational expression ever takes

  17. mathmath333
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    is infinite numbers answer

  18. ganeshie8
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    answer should be {0,1,2,3,4,5,6}

  19. Ehsan18
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    no but these numbers satisfy the equation

  20. mathmath333
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    oh ok thnx

  21. Ehsan18
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    what on earth the question says does not satisfy??

  22. ganeshie8
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    |dw:1434277279587:dw|

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

    The directions could be more clear. This might be better. "What integer values does the expression not attain. " or "What integer values does the function not attain. "

  24. 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.