A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • one year ago

Write the sum using summation notation, assuming the suggested pattern continues. -9 - 3 + 3 + 9 + ... + 81

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

    @surjithayer

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

    it is an A.P. a=-9 d=-3-(-9)=-3+9=6 find n by the the formula \[l=a+(n-1)d\] can you find n l=81

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

    are you here?

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

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

    these are answer options find n

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

    i did A @surjithayer

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

    i want to know how? can you show me ?

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

    @surjithayer i guessed im sry i suck at math

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

    ok.

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

    81=-9+(n-1)*6 81+9=(n-1)6 \[\frac{ 90 }{ 6 }=n-1\] n-1=15 n=15+1=16

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

    you got it.

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

    but on all of them n=0

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

    wait is it d?

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

    that means there are 16 terms for n=0,1,2,...,15

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

    here for A ,n=0 a1=-9 a2=-9+6*1=-3 a3=-9+6*2=3 ..... a16=-9+6*15=81

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

    I said A in the first place @surjithayer

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

    A is correct. as i have shown.

  18. dan815
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    would you like to see how sum of arithmetic series formula comes

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

    could u show me on this one? Write the sum using summation notation, assuming the suggested pattern continues. 5 - 15 + 45 - 135 + ...

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

    it is a G.P. can you find r?

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

    what is gp, i need it in summation notation

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

    gp means geometric progression

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

    for that you have to find r(common ratio)

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

    \[r=\frac{ t _{n} }{ t _{n-1} }\] to be precise 2nd term/1st term

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

    @surjithayer what one did u get as the answer

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

    \[r=\frac{ 45 }{ -15 }=?\]

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

    \[r=\frac{ -15 }{ 5 }=\frac{ 45 }{ -15 }=?\]

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

    @surjithayer its b right?

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

    r=-3 B is correct.

  30. 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.